draft-ietf-dmm-distributed-mobility-anchoring-00.txt		draft-ietf-dmm-distributed-mobility-anchoring-01.txt
	DMM H. Chan		DMM H. Chan, Ed.
	Internet-Draft X. Wei		Internet-Draft X. Wei
	Intended status: Informational Huawei Technologies		Intended status: Informational Huawei Technologies
	Expires: March 2, 2017 J. Lee		Expires: March 12, 2017 J. Lee
	Sangmyung University		Sangmyung University
	S. Jeon		S. Jeon
	Sungkyunkwan University		Sungkyunkwan University
			A. Petrescu
			CEA, LIST
	F. Templin		F. Templin
	Boeing Research and Technology		Boeing Research and Technology
	August 29, 2016		September 8, 2016
	Distributed Mobility Anchoring		Distributed Mobility Anchoring
	draft-ietf-dmm-distributed-mobility-anchoring-00		draft-ietf-dmm-distributed-mobility-anchoring-01
	Abstract		Abstract
	This document defines distributed mobility anchoring. Multiple		This document defines distributed mobility anchoring to meet diverse
	anchors and nodes are configured with appropriate mobility functions		mobility needs in 5G Wireless and beyond. Multiple anchors and nodes
	and work together to enable mobility solutions. Example solution is		with mobility functions work together to provide IP mobility support.
	mid-session switching of the IP prefix anchor. Without ongoing		A network or network slice may be configured with distributed
	session requiring session continuity, a flow can be started or re-		mobility anchoring with the needed behaviors depending on the needs
	started using the new IP prefix which is allocated from the new		of mobility support. In the distributed mobility anchoring
	network and is therefore anchored to the new network. With ongoing		environment, multiple anchors are available for mid-session switching
	session, the anchoring of the prior IP prefix may be relocated to the		of an IP prefix anchor. Without ongoing session requiring session
	new network to enable session continuity.		continuity, a flow can be re-started using a new IP prefix which is
			allocated from the new network and is therefore anchored to the new
			network. With ongoing session, the anchoring of the prior IP prefix
			may be relocated to the new network to enable session continuity.
	Status of This Memo		Status of This Memo
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	provisions of BCP 78 and BCP 79.		provisions of BCP 78 and BCP 79.
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	Task Force (IETF). Note that other groups may also distribute		Task Force (IETF). Note that other groups may also distribute
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	This Internet-Draft will expire on March 2, 2017.		This Internet-Draft will expire on March 12, 2017.
	Copyright Notice		Copyright Notice
	Copyright (c) 2016 IETF Trust and the persons identified as the		Copyright (c) 2016 IETF Trust and the persons identified as the
	document authors. All rights reserved.		document authors. All rights reserved.
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	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
	2. Conventions and Terminology . . . . . . . . . . . . . . . . . 3		2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4
	3. Distributed anchoring . . . . . . . . . . . . . . . . . . . . 5		3. Distributed Mobility Anchoring . . . . . . . . . . . . . . . 6
	3.1. Distributed anchoring configurations . . . . . . . . . . 5		3.1. Distributed Anchoring Configurations for Different
	3.2. Distributed anchoring behaviors and message information		Networks or Network Slices . . . . . . . . . . . . . . . 6
	elements . . . . . . . . . . . . . . . . . . . . . . . . 8		3.1.1. Distributed Anchoring with Network-based Mobility
	3.2.1. Location management behaviors and message information		Support for Flat Network . . . . . . . . . . . . . . 7
	elements . . . . . . . . . . . . . . . . . . . . . . 9		3.1.2. Distributed Anchoring with Network-based Mobility
	3.2.2. Forwarding management behaviors and message		Support for Hierarchical Network . . . . . . . . . . 8
	information elements . . . . . . . . . . . . . . . . 10		3.1.3. Distributed Anchoring for Host-based Mobility Support 11
	4. Example mobility solutions with distributed anchoring . . . . 12		3.2. Distributed Anchoring Behaviors and Mobility Message
	4.1. IP mobility support only when needed . . . . . . . . . . 12		Parameters . . . . . . . . . . . . . . . . . . . . . . . 13
	4.1.1. Not needed: Changing to the new IP prefix/address . . 13		3.2.1. Location Management Behaviors and Mobility Message
	4.1.2. Needed: Providing IP mobility support . . . . . . . . 14		Parameters . . . . . . . . . . . . . . . . . . . . . 13
	4.2. IP prefix/address anchor switching to the new network . . 16		3.2.2. Forwarding Management Behaviors and Mobility Message
	4.2.1. Centralized control plane . . . . . . . . . . . . . . 17		Parameters . . . . . . . . . . . . . . . . . . . . . 16
	4.2.2. Hierarchical network . . . . . . . . . . . . . . . . 20		4. IP Mobility Handling in Distributed Anchoring Environments -
	4.2.3. Hierarchical network with anchoring change . . . . . 22		Mobility Support Only When Needed . . . . . . . . . . . . . . 21
	5. Security Considerations . . . . . . . . . . . . . . . . . . . 23		4.1. No Need of IP Mobility: Changing to New IP Prefix/Address 22
	6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 24		4.1.1. Guidelines for IPv6 Nodes: Changing to New IP
	7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 24		Prefix/Address . . . . . . . . . . . . . . . . . . . 24
	8. References . . . . . . . . . . . . . . . . . . . . . . . . . 24		4.2. Need of IP Mobility . . . . . . . . . . . . . . . . . . . 26
	8.1. Normative References . . . . . . . . . . . . . . . . . . 24		4.2.1. Guidelines for IPv6 Nodes: Need of IP Mobility . . . 27
	8.2. Informative References . . . . . . . . . . . . . . . . . 26		5. IP Mobility Handling in Distributed Anchoring Environments -
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 26		Anchor Switching to the New Network . . . . . . . . . . . . . 28
			5.1. IP Prefix/Address Anchor Switching for Flat Network . . . 29
			5.1.1. Guidelines for IPv6 Nodes: Switching Anchor for Flat
			Network . . . . . . . . . . . . . . . . . . . . . . . 29
			5.2. IP Prefix/Address Anchor Switching for Flat Network with
			Centralized Control Plane . . . . . . . . . . . . . . . . 31
			5.2.1. Additional Guidelines for IPv6 Nodes: Switching
			Anchor with Centralized CP . . . . . . . . . . . . . 34
			5.3. IP Prefix/Address Anchor Switching for Hierarchical
			Network . . . . . . . . . . . . . . . . . . . . . . . . . 35
			5.3.1. Additional Guidelines for IPv6 Nodes: No Anchoring
			Change with Hierarchical Network . . . . . . . . . . 37
			5.4. IP Prefix/Address Anchor Switching for Hierarchical
			Network . . . . . . . . . . . . . . . . . . . . . . . . . 37
			5.4.1. Additional Guidelines for IPv6 Nodes: Switching
			Anchor with Hierarchical Network . . . . . . . . . . 39
			6. Security Considerations . . . . . . . . . . . . . . . . . . . 39
			7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 39
			8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 39
			9. References . . . . . . . . . . . . . . . . . . . . . . . . . 40
			9.1. Normative References . . . . . . . . . . . . . . . . . . 40
			9.2. Informative References . . . . . . . . . . . . . . . . . 42
			Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 42
	1. Introduction		1. Introduction
	A key requirement in distributed mobility management [RFC7333] is to		A key requirement in distributed mobility management [RFC7333] is to
	enable traffic to avoid traversing single mobility anchor far from		enable traffic to avoid traversing a single mobility anchor far from
	the optimal route. Distributed mobility management solutions do not		an optimal route. Distributed mobility management solutions do not
	make use of centrally deployed mobility anchor		make use of centrally deployed mobility anchor for the data plane
	[Paper-Distributed.Mobility]. As such, the traffic of a flow SHOULD		[Paper-Distributed.Mobility]. As such, the traffic of a flow SHOULD
	be able to change from traversing one mobility anchor to traversing		be able to change from traversing one mobility anchor to traversing
	another mobility anchor as the mobile node moves, or when changing		another mobility anchor as a mobile node moves, or when changing
	operation and management requirements call for mobility anchor		operation and management requirements call for mobility anchor
	switching, thus avoiding non-optimal routes. This draft proposes		switching, thus avoiding non-optimal routes. This draft proposes
	distributed mobility anchoring to enable making such route changes.		distributed mobility anchoring to enable making such route changes.
	Distributed mobility anchoring employs multiple anchors in the data		Distributed mobility anchoring employs multiple anchors in the data
	plane. In general, the control plane function may be separate from		plane. In general, the control plane function may be separate from
	the data plane functions and be centralized but may also co-located		the data plane functions and be centralized but may also be co-
	with the data plane function at these distributed anchors. Different		located with the data plane function at these distributed anchors.
	configurations (Section 3.1) of distributed anchoring are then		Different configurations (Section 3.1) of distributed mobility
	possible. Yet the distributed anchors need to have expected		anchoring are then possible. The configurations of distributed
	behaviors (Section 3.2).		anchoring for network-based mobility support in a flat network, for
			network-based mobility support in a hierarchical network, and for
			host-based mobility support are described respectively in
			Section 3.1.1, Section 3.1.2, and Section 3.1.3. Mobility functions
			at the anchors and nodes are required to perform with expected
			behaviors (Section 3.2). The LM behaviors and mobility message
			parameters are described in Section 3.2.1, whereas the FM behaviors
			and mobility message parameters are described in Section 3.2.2.
	A mobile node (MN) attached to an access router of a network may be		A mobile node (MN) attached to an access router of a network or
	allocated an IP prefix which is anchored to that router. It may then		network slice may be allocated an IP prefix which is anchored to that
	use the IP address configured from this prefix as the source IP		router. It may then use an IP address configured from this prefix as
	address to run a flow with its correspondent node (CN). When there		the source IP address to run a flow with its correspondent node (CN).
	are multiple anchors, the flow may need to select the anchor when it		When there are multiple anchors, an address selection for a given
	is initiated (Section 4). Using an anchor in MN's network of		flow is first required before the flow is initiated. Using an anchor
	attachment has the advantage that the packets can simply be forwarded		in MN's network of attachment has the advantage that the packets can
	according to the forwarding table. Although the anchor is in the		simply be forwarded according to the forwarding table. Although the
	MN's network of attachment when the flow was initiated, the MN may		anchor is in the MN's network of attachment when the flow was
	later move to another network, so that the IP address no longer		initiated, the MN may later move to another network, so that the IP
	belongs to the new network of attachment of the MN. Whether the flow		address no longer belongs to the current network of attachment of the
	needs session continuity will determine how to ensure that the IP		MN.
	address of the flow will be anchored to the new network of
	attachment. If the ongoing IP flow can cope with an IP prefix/		Whether the flow needs session continuity will determine how to
	address change, the flow can be reiniated with a new IP address		ensure that the IP address of the flow will be anchored to the new
	anchored in the new network (Section 4.1.1). On the other hand, if		network of attachment. If the ongoing IP flow can cope with an IP
	the ongoing IP flow cannot cope with such change, the IP address		prefix/address change, the flow can be reinitiated with a new IP
	anchoring can be moved from the original network to the new network		address anchored in the new network (Section 4.1). On the other
	(Section 4.2).		hand, if the ongoing IP flow cannot cope with such change, mobility
			support is needed (Section 4.2). A network or network slice
			supporting a mix of flows requiring and not requiring IP mobility
			support will need to distinguish these flows. The guidelines for
			such network or network slice are described in Section 4.1.1. The
			general guidelines for such network or network slice to provide IP
			mobility support are described in Section 4.2.1.
			Specifically, IP mobility support can be provided by changing the
			anchoring of the IP prefix/address of the flow from the home network
			of the flow to the new network of attachment Section 5. The basic
			case may be with network-based mobility for a flat network
			configuration described in Section 5.1 with the guidelines described
			in Section 5.1.1. This case is discussed further with a centralized
			control plane in Section 5.2 with additional guidelines described in
			Section 5.2.1. A level of hierarchy of nodes may then be added to
			the network configuration. Mobility involving change in the DPN
			without changing the DPA is described in Section 5.3 with additional
			guidelines described in Section 5.3.1 Mobility involving change in
			the DPN without changing the DPA is described in Section 5.4 with
			additional guidelines described in Section 5.4.1
	2. Conventions and Terminology		2. Conventions and Terminology
	The key words "MUST", "MUST NOT", "REQUIRED", "SHALL","SHALL NOT",		The key words "MUST", "MUST NOT", "GLUIRED", "SHALL","SHALL NOT",
	"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this		"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
	document are to be interpreted as described in [RFC2119].		document are to be interpreted as described in [RFC2119].
	All general mobility-related terms and their acronyms used in this		All general mobility-related terms and their acronyms used in this
	document are to be interpreted as defined in the Mobile IPv6 base		document are to be interpreted as defined in the Mobile IPv6 (MIPv6)
	specification [RFC6275], the Proxy Mobile IPv6 specification		base specification [RFC6275], the Proxy Mobile IPv6 (PMIPv6)
	[RFC5213], and the DMM current practices and gap analysis [RFC7429].		specification [RFC5213], the "Mobility Related Terminologies"
	This includes terms such as mobile node (MN), correspondent node		[RFC3753], and the DMM current practices and gap analysis [RFC7429].
			These include terms such as mobile node (MN), correspondent node
	(CN), home agent (HA), home address (HoA), care-of-address (CoA),		(CN), home agent (HA), home address (HoA), care-of-address (CoA),
	local mobility anchor (LMA), and mobile access gateway (MAG).		local mobility anchor (LMA), and mobile access gateway (MAG).
	In addition, this document uses the following term:		In addition, this document uses the following terms:
	Home network of an application session (or of an HoA): the network		Home network of an application session (or of an HoA): the network
	that has allocated the IP address (HoA) used for the session		that has allocated the IP address (HoA) used for the session
	identifier by the application running in an MN. An MN may be		identifier by the application running in an MN. The MN may be
	running multiple application sessions, and each of these sessions		running multiple application sessions, and each of these sessions
	can have a different home network.		can have a different home network.
	IP prefix/address anchoring: An IP prefix, i.e., Home Network Prefix		IP prefix/address anchoring: An IP prefix, i.e., Home Network Prefix
	(HNP), or address, i.e., Home Address (HoA), allocated to a mobile		(HNP), or address, i.e., Home Address (HoA), allocated to a mobile
	node is topologically anchored to a node when the anchor node is		node is topologically anchored to an anchor node when the anchor
	able to advertise a connected route into the routing		node is able to advertise a connected route into the routing
	infrastructure for the allocated IP prefix.		infrastructure for the allocated IP prefix.
	Internetwork Location Management (LM) function: managing and keeping		Internetwork Location Management (LM) function: managing and keeping
	track of the internetwork location of an MN. The location		track of the internetwork location of an MN. The location
	information may be a binding of the IP advertised address/prefix,		information may be a binding of the IP advertised address/prefix,
	e.g., HoA or HNP, to the IP routing address of the MN or of a node		e.g., HoA or HNP, to the IP routing address of the MN or of a node
	that can forward packets destined to the MN. It is a control		that can forward packets destined to the MN.
	plane function.
			When the MN is a mobile router (MR) carrying a mobile network of
			mobile network nodes (MNN), the location information will also
			include the IP prefixes delegated to the MR to be allocated to the
			MNNs in the mobile network.
			LM is a control plane function.
	In a client-server protocol model, location query and update		In a client-server protocol model, location query and update
	messages may be exchanged between a Location Management client		messages may be exchanged between a Location Management client
	(LMc) and a Location Management server (LMs).		(LMc) and a Location Management server (LMs).
			Optionally, there may be a Location Management proxy (LMp) between
			LMc and LMs.
	With separation of control plane and data plane, the LM function		With separation of control plane and data plane, the LM function
	is in the control plane. It may be a logical function at the		is in the control plane. It may be a logical function at the
	control plane node, control plane anchor, or mobility controller.		control plane node, control plane anchor, or mobility controller.
	It may be distributed or centralized.		It may be distributed or centralized.
	Forwarding Management (FM) function: packet interception and		Forwarding Management (FM) function: packet interception and
	forwarding to/from the IP address/prefix assigned to the MN, based		forwarding to/from the IP address/prefix assigned to the MN, based
	on the internetwork location information, either to the		on the internetwork location information, either to the
	destination or to some other network element that knows how to		destination or to some other network element that knows how to
	forward the packets to their destination.		forward the packets to their destination.
	This function may be used to achieve indirection. With separation		This function may be used to achieve traffic indirection. With
	of control plane and data plane, FM may split into a FM function		separation of control plane and data plane, the FM function may
	in the data plane (FM-DP) and a FM function in the control plane		split into a FM function in the data plane (FM-DP) and a FM
	(FM-CP).		function in the control plane (FM-CP).
	FM-DP may be distributed with distributed mobility management. It		FM-DP may be distributed with distributed mobility management. It
	may be a function in a data plane anchor or data plane node.		may be a function in a data plane anchor or data plane node.
	FM-CP may be distributed or centralized. It may be a function in		FM-CP may be distributed or centralized. It may be a function in
	a control plane node, control plane anchor or mobility controller.		a control plane node, control plane anchor or mobility controller.
	Security Management (SM) function: The security management function		Security Management (SM) function: The security management function
	controls security mechanisms/protocols providing access control,		controls security mechanisms/protocols providing access control,
	integrity, authentication, authorization, confidentiality, etc.		integrity, authentication, authorization, confidentiality, etc.
	for the control plane and data plane.		for the control plane and data plane.
	This function resides in all nodes such as control plane anchor,		This function resides in all nodes such as control plane anchor,
	data plane anchor, mobile node, and correspondent node.		data plane anchor, mobile node, and correspondent node.
	3. Distributed anchoring		3. Distributed Mobility Anchoring
	3.1. Distributed anchoring configurations		3.1. Distributed Anchoring Configurations for Different Networks or
			Network Slices
	The mobility functions may be implemented in different configurations		The mobility functions may be implemented in different configurations
	of distributed anchoring in architectures separating the control and		of distributed anchoring in architectures separating the control and
	data planes. The separation as described in		data planes. The separation as described in
	[I-D.wt-dmm-deployment-models] has defined home control plane anchor		[I-D.ietf-dmm-deployment-models] has defined home control plane
	(Home-CPA), home data plane anchor (Home-DPA), access control plane		anchor (Home-CPA), home data plane anchor (Home-DPA), access control
	node (Access-CPN), and access data plane node (Access-DPN), which are		plane node (Access-CPN), and access data plane node (Access-DPN),
	respectively abbreviated as CPA, DPA, CPN, and DPN here. Some		which are respectively abbreviated as CPA, DPA, CPN, and DPN here.
	configurations are described in [I-D.sijeon-dmm-deployment-models].		Some configurations are described in
			[I-D.sijeon-dmm-deployment-models].
	Figure 1 shows 4 configurations of network-based mobility management.		Different networks or different network slices may have different
	In each configuration, an MN is allocated an IP prefix/address IP1		configurations of distributed anchoring.
	and is using IP1 to communicate with a correspondent node (CN) not
	shown in the figure. The flow of this communication session is shown
	as flow(IP1, ...) which uses IP1 and other parameters.
	(a) (b) (c) (d)		The configurations also differ depending on whether the desired
	+-----+ +-----+		mobility support is network-based for a flat network (Section 3.1.1),
	|LMs | |LMs |		is network-based for a hierarchical network (Section 3.1.2), or is
	+-----+ +-----+		host-based (Section 3.1.3).
	+------------+ +------------+ +------------+ +------------+		3.1.1. Distributed Anchoring with Network-based Mobility Support for
	|CPA: | |CPA: | |CPA: | |CPA: |		Flat Network
	|FM-CP, LM | |FM-CP, LMc | |FM-CP, LMs | |FM-CP, LMp |
	+------------+ +------------+ +------------+ +------------+
	+------------+ +------------+ +------------+ +------------+
	|DPA(IPa1): | |DPA(IPa1): | |DPA(IPa1): | |DPA(IPa1): |
	|anchors IP1 | |anchors IP1 | |anchors IP1 | |anchors IP1 |
	|FM-DP | |FM-DP | |FM-DP | |FM-DP |
	+------------+ +------------+ +------------+ +------------+
	+------------+ +------------+		Figure 1 shows 2 configurations of network-based mobility management
	|CPN: | |CPN: |		for a flat network.
	|FM-CP, LMc | |FM-CP, LMc |
	+------------+ +------------+
	+------------+ +------------+
	|DPN(IPn1): | |DPN(IPn1): |
	|FM-DP | |FM-DP |
	+------------+ +------------+
	+------------+ +------------+ +------------+ +------------+		(a) (b)
	|MN(IP1) | |MN(IP1) | |MN(IP1) | |MN(IP1) |		+-----+
	|flow(IP1,..)| |flow(IP1,..)| |flow(IP1,..)| |flow(IP1,..)|		|LMs |
	+------------+ +------------+ +------------+ +------------+		+-----+
	Figure 1. (a) FM-CP and LM at CPA, FM-DP at DPA; (b) Separate LMs,		+------------+ +------------+
	FM-CP and LMc at CPA, FM-DP at DPA; (c) FM-CP and LMs at CPA, FM-DP		|CPA: | |CPA: |
	at DPA, FM-CP and LMc at CPN, FM-DP at DPN; (d) Separate LMs, FM-CP		|FM-CP, LM | |FM-CP, LMc |
	and LMp at CPA, FM-DP at DPA, FM-CP and LMc at CPN, FM-DP at DPN.		+------------+ +------------+
			+------------+ +------------+ +------------+ +------------+
			|DPA(IPa1): | |DPA(IPa2): | |DPA(IPa1): | |DPA(IPa2): |
			|anchors IP1 | |anchors IP2 | ... |anchors IP1 | |anchors IP2 | ...
			|FM-DP | |FM-DP | |FM-DP | |FM-DP |
			+------------+ +------------+ +------------+ +------------+
	In Figures 1(a), 1(b), 1(c), and 1(d), the IP address of the MN, IP1,		+------------+ +------------+
	is anchored to the DPA which has the IP prefix/address IPa1. The		|MN(IP1) | |MN(IP1) |
	data plane is distributed so that there may be multiple instances of		|flow(IP1,..)| |flow(IP1,..)|
	the DPA (not shown). The control plane may either be distributed or		+------------+ +------------+
			Figure 1. Configurations of network-based mobility management for a
			flat network (a) FM-CP and LM at CPA, FM-DP at DPA; (b) Separate LMs,
			FM-CP and LMc at CPA, FM-DP at DPA.
			Figure 1 also shows a distributed mobility anchoring environment with
			multiple instances of the DPA.
			There is FM-DP function at each of the distributed DPA.
			The control plane may either be distributed (not shown) or
	centralized. When the CPA co-locates with the distributed DPA there		centralized. When the CPA co-locates with the distributed DPA there
	will be multiple instances of the co-located CPA and DPA (not shown).		will be multiple instances of the co-located CPA and DPA (not shown).
	In Figure 1(a) and Figure 1(b), the network is flat with FM-DP at the		There is FM-CP function at the CPA.
	distributed DPA.
	In Figure 1(a), LM and FM-CP co-locate at CPA. Then LM may be		MN is allocated an IP prefix/address IP1 which is anchored to the DPA
	distributed or centralized according to whether the CPA is		with the IP prefix/address IPa1. It is using IP1 to communicate with
	distributed or centralized.		a correspondent node (CN) not shown in the figure. The flow of this
			communication session is shown as flow(IP1, ...) which uses IP1 and
			other parameters.
			In Figure 1(a), LM and FM-CP co-locate at CPA.
			Then LM may be distributed or centralized according to whether the
			CPA is distributed (not shown) or centralized.
	Figure 1(b) differs from Figure 1(a) in that the LM function is split		Figure 1(b) differs from Figure 1(a) in that the LM function is split
	into a server LMs and a client LMc. LMc and FM-CP are at the CPA.		into a server LMs and a client LMc.
			LMc and FM-CP co-locate at the CPA.
	The LMs may be centralized whereas the LMc may be distributed or		The LMs may be centralized whereas the LMc may be distributed or
	centralized according to whether the CPA is distributed or		centralized according to whether the CPA is distributed (not shown)
			or centralized.
			3.1.2. Distributed Anchoring with Network-based Mobility Support for
			Hierarchical Network
			Figure 2 shows 2 configurations of network-based mobility management
			for a hierarchical network.
			(a)
			+------------+
			|CPA: |
			|FM-CP, LMs |
			+------------+
			+------------+ +------------+
			|DPA(IPa1): | |DPA(IPa2): |
			|anchors IP1 | |anchors IP2 | ...
			|FM-DP | |FM-DP |
			+------------+ +------------+
			+------------+
			|CPN: |
			|FM-CP, LMc |
			+------------+
			+------------+ +------------+ +------------+ +------------+
			|DPN(IPn11): | |DPN(IPn12): | |DPN(IPn21): | |DPN(IPn22) |
			|FM-DP | |FM-DP | ... |FM-DP | |FM-DP | ...
			+------------+ +------------+ +------------+ +------------+
			+------------+ +------------+
			|MN(IP1) | |MN(IP2) |
			|flow(IP1,..)| |flow(IP2,..)|
			+------------+ +------------+
			Figure 2(a). Configurations of network-based mobility management for
			a hierarchical network with FM-CP and LMs at CPA, FM-DP at DPA; FM-CP
			and LMc at CPN, FM-DP at DPN.
			(b)
			+-----+
			|LMs |
			+-----+
			+------------+
			|CPA: |
			|FM-CP, LMp |
			+------------+
			+------------+ +------------+
			|DPA(IPa1): | |DPA(IPa2): |
			|anchors IP1 | |anchors IP2 | ...
			|FM-DP | |FM-DP |
			+------------+ +------------+
			+------------+
			|CPN: |
			|FM-CP, LMc |
			+------------+
			+------------+ +------------+ +------------+ +------------+
			|DPN(IPn11): | |DPN(IPn12): | |DPN(IPn21): | |DPN(IPn22) |
			|FM-DP | |FM-DP | ... |FM-DP | |FM-DP | ...
			+------------+ +------------+ +------------+ +------------+
			+------------+ +------------+
			|MN(IP1) | |MN(IP2) |
			|flow(IP1,..)| |flow(IP2,..)|
			+------------+ +------------+
			Figure 2(b). Configurations of network-based mobility management for
			a hierarchical network with separate LMs, FM-CP and LMp at CPA, FM-DP
			at DPA; FM-CP and LMc at CPN, FM-DP at DPN.
			Figures 2 also shows a distributed mobility anchoring environment
			with multiple instances of the DPA.
			In the hierarchy, there may be multiple DPN's for each DPA.
			There is FM-DP at each of the distributed DPA and at each of the
			distributed DPN.
			The control plane may either be distributed (not shown) or
	centralized.		centralized.
	In Figure 1(c) and Figure 1(d), the network is hierarchical where		When the CPA co-locates with the distributed DPA there will be
	there may be multiple DPN's for each DPA. There is FM-DP at each of		multiple instances of the co-located CPA and DPA (not shown).
	the distributed DPA and at each of the distributed DPN.
	In Figure 1(c), LMs and FM-CP are at the CPA. In addition, there are		When the CPN co-locates with the distributed DPN there will be
	FM-CP and LMc at the CPN. Again, LMs may be distributed or		multiple instances of the co-located CPN and DPN (not shown).
			There is FM-CP function at the CPA and at the CPN.
			MN is allocated an IP prefix/address IP1 which is anchored to the DPA
			with the IP prefix/address IPa1. It is using IP1 to communicate with
			a correspondent node (CN) not shown in the figure. The flow of this
			communication session is shown as flow(IP1, ...) which uses IP1 and
			other parameters.
			In Figure 2(a), LMs and FM-CP are at the CPA. In addition, there are
			FM-CP and LMc at the CPN.
			LMs may be distributed or centralized according to whether the CPA is
			distributed or centralized. The CPA may co-locate with DPA or may
			separate.
			Figure 2(b) differs from Figure 2(a) in that the LMs is separated
			out, and a proxy LMp is added between the LMs and LMc.
			LMp and FM-CP co-locate at the CPA.
			FM-CP and LMc co-locate at the CPN.
			The LMs may be centralized whereas the LMp may be distributed or
	centralized according to whether the CPA is distributed or		centralized according to whether the CPA is distributed or
	centralized. The CPA may co-locate with DPA or may separate.		centralized.
	Figure 1(d) differs from Figure 1(c) in that the LMs is separated		3.1.3. Distributed Anchoring for Host-based Mobility Support
	out, and a proxy LMp is added between the LMs and LMc. LMp and FM-CP
	are at the CPA. Again, there are FM-CP and LMc at the CPN. The LMs
	may be centralized whereas the LMp may be distributed or centralized
	according to whether the CPA is distributed or centralized.
	Host-based variants of the mobility function configurations from		Host-based variants of the mobility function configurations from
	Figures 1(c) and 1(d) are shown in Figures 2(a) and 2(b) where the		Figures 2(a) and 2(b) are respectively shown in Figures 3(a) and 3(b)
	role to perform mobility functions by CPN and DPN are now taken by		where the role to perform mobility functions by CPN and DPN are now
	the MN. The MN then need to possess the mobility functions FM and		taken by the MN. The MN then needs to possess the mobility functions
	LMc.		FM and LMc.
	(a) (b)		(a) (b)
	+-----+		+-----+
	|LMs |		|LMs |
	+-----+		+-----+
	+------------+ +------------+		+------------+ +------------+
	|CPA: | |CPA: |		|CPA: | |CPA: |
	|FM-CP, LMs | |FM-CP, LMp |		|FM-CP, LMs | |FM-CP, LMp |
	+------------+ +------------+		+------------+ +------------+
	+------------+ +------------+		+------------+ +------------+ +------------+ +------------+
	|DPA(IPa1): | |DPA(IPa1): |		|DPA(IPa1): | |DPA(IPa2): | |DPA(IPa1): | |DPA(IPa2): |
	|anchors IP1 | |anchors IP1 |		|anchors IP1 | |anchors IP2 | ... |anchors IP1 | |anchors IP2 | ...
	|FM-DP | |FM-DP |		|FM-DP | |FM-DP | |FM-DP | |FM-DP |
	+------------+ +------------+		+------------+ +------------+ +------------+ +------------+
	+------------+ +------------+		+------------+ +------------+
	|MN(IP1) | |MN(IP1) |		|MN(IP1) | |MN(IP1) |
	|flow(IP1,..)| |flow(IP1,..)|		|flow(IP1,..)| |flow(IP1,..)|
	|FM, LMc | |FM, LMc |		|FM, LMc | |FM, LMc |
	+------------+ +------------+		+------------+ +------------+
	Figure 2. (a) FM-CP and LMs at CPA, FM-DP at DPA, FM and LMc at MN;		Figure 3. Configurations of host-based mobility management (a) FM-CP
	(b) Separate LMs, FM-CP and LMp at CPA, FM-DP at DPA, FM and LMc at		and LMs at CPA, FM-DP at DPA, FM and LMc at MN; (b) Separate LMs, FM-
	MN.		CP and LMp at CPA, FM-DP at DPA, FM and LMc at MN.
	In Figure 2(a) and Figure 2(b), FM-DP is at the distributed DPA as		Figure 3 shows 2 configurations of host-based mobility management
	before.		with multiple instances of DPA for a distributed mobility anchoring
			environment.
	In Figure 2(a), LMs and FM-CP are at the CPA. The LMs may be		There is FM-DP function at each of the distributed DPA.
	distributed or centralized according to whether the CPA is
	distributed or centralized.
	Figure 2(b) differs from Figure 2(a) in that the LMs is separated out		The control plane may either be distributed (not shown) or
	and the proxy LMp is added between the LMs and LMc. LMp and FM-CP		centralized.
	are at the CPA. The FMs may be centralized whereas the LMp may be
	distributed or centralized according to whether the CPA is
	distributed or centralized.
	3.2. Distributed anchoring behaviors and message information elements		When the CPA co-locates with the distributed DPA there will be
			multiple instances of the co-located CPA and DPA (not shown).
			There is FM-CP function at the CPA.
			The MN possesses the mobility functions FM and LMc.
			MN is allocated an IP prefix/address IP1 which is anchored to the DPA
			with the IP prefix/address IPa1. It is using IP1 to communicate with
			a correspondent node (CN) not shown in the figure. The flow of this
			communication session is shown as flow(IP1, ...) which uses IP1 and
			other parameters.
			In Figure 3(a), LMs and FM-CP co-locate at the CPA.
			The LMs may be distributed or centralized according to whether the
			CPA is distributed (not shown) or centralized.
			Figure 3(b) differs from Figure 3(a) in that the LMs is separated out
			and the proxy LMp is added between the LMs and LMc.
			LMp and FM-CP co-locate at the CPA.
			The LMs may be centralized whereas the LMp may be distributed or
			centralized according to whether the CPA is distributed (not shown)
			or centralized.
			3.2. Distributed Anchoring Behaviors and Mobility Message Parameters
	The behaviors of distributed anchoring are defined in this section in		The behaviors of distributed anchoring are defined in this section in
	order that they may work together in expected manners to produce a		order that they may work together in expected manners to produce a
	distributed mobility solution. The needed information elements are		distributed mobility solution. The needed information are passed as
	passed as message parameters.		mobility message parameters.
	3.2.1. Location management behaviors and message information elements		The mobility needs in 5G Wireless and beyond are diverse. Therefore
			the behaviors needed to enable different distributed mobility
			solutions in different distributed anchoring configurations are
			extensive and are listed below. It is however not necessary for
			every distributed mobility solution to exhibit all the behaviors
			listed in this section. A given distributed mobility solution may
			exhibit the behaviors as needed.
	It is seen in (Section 3.1) that		3.2.1. Location Management Behaviors and Mobility Message Parameters
	(1) LMs may be a separate server or may co-locate with LMc at CPA;		An example LM design consists of a distributed database with multiple
	(2) LMc may be at CPA, CPN, or MN.		LMs servers. The location information about the prefix/address of an
			MN is primarily at a given LMs. Peer LMs may exchange the location
			information with each other. LMc may retrieve a given record or send
			a given record update to LMs.
	Example LM design may consists of a distributed database of LMs		Location management behaviors:
	servers in a pool of distributed servers. The location information
	about the prefix/address of a MN is primarily at a given LMs. Peer
	LMs may exchange the location information with each other. LMc may
	retrieve a given record or send a given record update to LMs.
	Location information bebaviors:		LM-cfg: As shown in Section 3.1:
	(LM:1) LM may manage the location information in a client-server		LMs may be implemented at CPA, may co-locate with LMc at CPA,
	database system. The example LM database functions are:		or may be a separate server.
	(LM:1-1) LMc may query LMs about location information for a		LMc may be at CPA, CPN, or MN.
	prefix of MN (pull).
	Parameters:
	IP prefix of MN.
	(LM:1-2) LMs may reply to LMc query about location		LMp may proxy between LMs and LMc.
	information for a prefix of MN (pull).
	Parameters:
	IP prefix of MN,
	IP address of FM-DP/DPA/DPN to forward the packets
	of the flow.
	(LM:1-3) LMs may inform LMc about location information for a		Specifically:
	prefix of MN (push).
	Parameters:
	IP prefix of MN,
	IP address of FM-DP/DPA/DPN to forward the packets
	of the flow.
	(LM:1-4) LMc may inform LMs about update location		LM-cfg:1 LMs may co-locate with LMc at CPA in a flat network with
	information for a prefix of MN.		network-based mobility as shown in Figure 1(a) in
	Parameters:		Section 3.1.1.
	IP prefix of MN,
	IP address of FM-DP/DPA/DPN to forward the packets
	of the flow.
	(LM:2) The LM may be a distributed database with multiple LMs		LM-cfg:2 LMs may be a separate server whereas LMc is implemented in
	servers. For example:		CPA in a flat network with network-based mobility as shown
			in Figure 1(b) in Section 3.1.1.
	(LM:2-1) A LMs may join a pool of LMs servers.		LM-cfg:3 LMs may be implemented at CPA, whereas LMc is implemented
			at CPN in a hierarchical network with network-based
			mobility as shown in Figure 2(a) in Section 3.1.2 or at MN
			for host-based mobility as shown in Figure 3(a) in
			Section 3.1.3.
	Parameters:		LM-cfg:4 LMs may be a separate server with LMp implemented at CPA
	IP address of the LMs,		whereas LMc is implemented at CPN in a hierarchical network
	IP prefixes for which the LMs will host the primary		with network-based mobility as shown in Figure 2(b) in
	location information.		Section 3.1.2 or at MN for host-based mobility as shown in
			Figure 3(b) in Section 3.1.3.
	(LM:2-2) LMs may query a peer LMs about location information		LM-db: LM may manage the location information in a client-server
	for a prefix of MN.		database system.
	Parameters:
	IP prefix.
	(LM:2-3) LMs may reply to a peer LMs about location		Example LM database functions are as follows:
	information for a prefix of MN.
	Parameters:
	IP prefix of MN,
	IP address of FM-DP/DPA/DPN to forward the packets
	of the flow.
	3.2.2. Forwarding management behaviors and message information elements		LM-db:1 LMc may query LMs about location information for a prefix of
			MN (pull).
			Parameters:
			IP prefix of MN.
	It is seen in (Section 3.1) that		LM-db:2 LMs may reply to LMc query about location information for a
			prefix of MN (pull).
			Parameters:
			IP prefix of MN,
			IP address of FM-DP/DPA/DPN to forward the packets of the
			flow.
	(1) FM-CP may be at CPA, CPN, MN;		LM-db:3 LMs may inform LMc about location information for a prefix
	(2) FM-DP may be at DPA, DPN, MN.		of MN (push).
			Parameters:
			IP prefix of MN,
			IP address of FM-DP/DPA/DPN to forward the packets of the
			flow.
	The FM behaviors and message information elements are:		This function in PMIPv6 protocol is the Update Notification
			(UPN) together with the Update Notification Acknowledgment
			(UPA) as defined in [RFC7077].
	(FM:1) With distributed FM functions, the role of FM for a flow may		LM-db:4 LMc may inform LMs about update location information for a
	pass to another FM as the DPA or DPN changes.		prefix of MN.
			Parameters:
			IP prefix of MN,
			IP address of FM-DP/DPA/DPN to forward the packets of the
			flow.
	(FM:2) In addition to above, a flow/session may be stateful for the		This function in MIPv6 / PMIPv6 protocol is the Binding
	required information for QoS, charging, etc. are needed.		Update (BU) / Proxy Binding Update (PBU) together with the
	These states need to be transferred from the old anchor to		Binding Acknowledgment (BA) / Proxy Binding Acknowledgment
	the new anchor.		(PBA) as defined in [RFC6275] / [RFC5213] respectively.
	(FM:3) An anchor may act on packets on a per flow basis and perform		LM-db:5 The MN may be a host or a router. When the MN is a mobile
	the changes to the forwarding path upon a change of point of		router (MR), the prefix information above may include the
	attachment of a MN:		prefixes delegated to the MR.
			Additional parameters:
			IP prefix or prefixes delegated to the MR.
	(FM:3-1) FM filters the packets up to the granularity of a		LM-svr: The LM may be a distributed database with multiple LMs
	flow.		servers.
	Example matching parameters are the 5-tuple of a
	flow.
	(FM:3-2) FM makes the necessary changes to the forwarding		For example:
	path of a flow.
	Example mechanism is through forwarding table
	update activated by DHCPv6-PD.
	(FM:3-3) FM reverts the previously made changes to the		LM-svr:1 A LMs may join a pool of LMs servers.
	forwarding path of a flow when such changes are no		Parameters:
	longer needed, e.g., when ongoing flows using an IP		IP address of the LMs,
	prefix/address requiring session continuity have		IP prefixes for which the LMs will host the primary
	closed.		location information.
	Example mechanism is through expiration of
	DHCPv6-PD.
	(FM:4) An anchor may discover and be discovered such as through an		LM-svr:2 LMs may query a peer LMs about location information for a
	anchor registration system:		prefix of MN.
			Parameters:
			IP prefix.
	(FM:4-1) FM registers and authenticates itself with a		LM-svr:3 LMs may reply to a peer LMs about location information for
	centralized mobility controller.		a prefix of MN.
	Parameters:		Parameters:
	IP address of DPA and its CPA;		IP prefix of MN,
	IP prefix anchored to the DPA.		IP address of FM-DP/DPA/DPN to forward the packets of the
			flow.
	(FM:4-2) registration reply: acknowledge of registration and		The parameters indicated above are only the minimal. In a specific
	echo the input parameters.		mobility protocol, additional parameters should be added as needed.
	(FM:4-3) FM discovers the FM of another IP prefix by		Examples of these additional parameters are those passed in the
	querying the mobility controller based on the IP		mobility options of the mobility header for MIPv6 [RFC6275] and for
	prefix.		PMIPv6 [RFC5213].
	Parameters:
	IP prefix of MN.
	(FM:4-4) when making anchor discovery FM expects the answer		3.2.2. Forwarding Management Behaviors and Mobility Message Parameters
	parameters as: IP address of DPA to which IP prefix
	of MN is anchored; IP prefix of the corresponding
	CPA.
	(FM:5) With separation of control plane function and data plane		The FM behaviors and mobility message parameters are:
	function, these function must work together.
	(FM:5-1) CPA/FM-CP sends forwarding table updates to DPA/FM-		FM-cfg: As shown in Section 3.1:
	DP.
	Parameters:
	new forwarding table entries to add;
	expired forwarding table entries to delete.
	(FM:5-2) DPA/FM-DP sends to CPA/FM-CP about its status and		FM-CP may be implemented at CPA, CPN, MN depending on the
	load.		configuration chosen.
	Parameters:
	state of forwarding function being active or not;
	loading percentage.
	(FM:6) An anchor can buffer packets of a flow in a mobility event:		FM-DP may also be implemented at CPA, CPN, MN depending on
			the configuration chosen.
	(FM:6-1) CPA/FM-CP informs DPA/FM-DP to buffer packets of a		Specifically:
	flow.
	Trigger:
	MN leaves DPA in a mobility event.
	Parameters:
	IP prefix of the flow for which packets need to be
	buffered.
	(FM:6-2) CPA/FM-CP on behalf of a new DPA/FM-DP informs the		FM-cfg:1 FM-CP and FM-DP may be implemented at CPA and DPA
	CPA/FM-CP of the prior DPA/FM-DP that it is ready		respectively in a flat network with network-based mobility
	to receive any buffered packets of a flow.		as shown in Figure 1(a) and Figure 1(b) in Section 3.1.1.
	Parameters:
	destination IP prefix of the flow's packets;
	IP address of the new DPA.
	4. Example mobility solutions with distributed anchoring		FM-cfg:2 FM-CP may be implemented at both CPA and CPN and FM-DP is
			implemented at both DPA and DPN in a hierarchical network
			with network-based mobility as shown in Figure 2(a) and
			Figure 2(b) in Section 3.1.2.
	The IP prefix/address at the MN's side of a flow may be anchored at		FM-cfg:3 FM-CP and FM-DP may be implemented at CPA and DPA
	the access router to which the MN is attached. For example, when an		respectively and also both implemented at MN for host-based
	MN attaches to a network (Net1) or moves to a new network (Net2), it		mobility as shown in Figure 3(a) and Figure 3(b) in
	is allocated an IP prefix from that network. It configures from this		Section 3.1.3.
	prefix an IP address which is typically a dynamic IP address. It
	then uses this IP address when a flow is initiated. Packets to the
	MN in this flow are simply forwarded according to the forwarding
	table.
	There may be multiple IP prefixes/addresses to choose from. They may		FM-find:1 An anchor may discover and be discovered such as through
	be from the same access network or different access networks. The		an anchor registration system as follows:
	network may advertise these prefixes with cost options
	[I-D.mccann-dmm-prefixcost] so that the mobile node may choose the
	one with the least cost. In addition, these IP prefixes/addresses
	may be of different types regarding whether mobility support is
	needed [I-D.ietf-dmm-ondemand-mobility]. A flow will need to choose
	the appropriate one according to whether it needs IP mobility
	support.
	4.1. IP mobility support only when needed		FM-find:2 FM registers and authenticates itself with a centralized
			mobility controller.
			Parameters:
			IP address of DPA and its CPA;
			IP prefix anchored to the DPA.
			registration reply: acknowledge of registration and echo
			the input parameters.
			FM-find:3 FM discovers the FM of another IP prefix by querying the
			mobility controller based on the IP prefix.
			Parameters:
			IP prefix of MN.
			FM-find:4 when making anchor discovery FM expects the answer
			parameters as: IP address of DPA to which IP prefix of MN
			is anchored; IP prefix of the corresponding CPA.
			FM-flow:1 The FM may be carried out on the packets to/from an MN up
			to the granularity of a flow.
			FM-flow:2 Example matching parameters are in the 5-tuple of a flow.
			FM-cpdp:1 With separation of control plane function and data plane
			function, FM-CP and FM-DP communicate with each other.
			Such communication may be realized by the appropriate
			messages in [I-D.ietf-dmm-fpc-cpdp]. For example:
			FM-cpdp:2 CPA/FM-CP sends forwarding table updates to DPA/FM-DP.
			Parameters:
			new forwarding table entries to add;
			expired forwarding table entries to delete.
			FM-cpdp:3 DPA/FM-DP sends to CPA/FM-CP about its status and load.
			Parameters:
			state of forwarding function being active or not;
			loading percentage.
			FM-path:1 FM may change the forwarding path of a flow upon a change
			of point of attachment of a MN. Prior to the changes,
			packets coming from the CN to the MN would traverse from
			the CN to the home network anchor of the flow for the MN
			before reaching the MN. Changes are from this original
			forwarding path or paths to a new forwarding path or paths
			from the CN to the current AR of the MN and then the MN
			itself.
			FM-path:2 As an incoming packet is forwarded from the CN to the MN,
			the far end where forwarding path change begins may in
			general be any node in the original forwarding path from
			the CN to the home network DPA. The packet is forwarded
			to the MN for host-based mobility and to a node in the
			network which will deliver the packets to the MN for
			network-based mobility. The near-end is generally a DPN
			with a hierarchical network but may also be another node
			with DPA capability in a flattened network.
			FM-path:3 The mechanisms to accomplish such changes may include
			changes to the forwarding table and indirection such as
			tunneling, rewriting packet header, or NAT.
			Note: An emphasis in this document in distributed mobility
			anchoring is to explain the use of multiple anchors to
			avoid unnecessarily long route which may be encountered in
			centralized mobility anchoring. It is therefore not the
			emphasis of this document on which particular mechanism to
			choose from.
			FM-path-tbl:4 With forwarding table updates, changes to the
			forwarding table are needed at each of the affected
			forwarding switches in order to change the forwarding
			path of the packets for the flow from that originally
			between the CN and the home network anchor to that
			between the CN and the new AR.
			Forwarding table updates may be achieved through BGP
			update, but such updates may only be practical when
			its scope is confined. An alternative is through
			messaging between a centralized control plane and the
			distributed forwarding switches.
			Forwarding table updates may be triggered using
			DHCPv6-PD prefix delegation to change the role of IP
			anchoring from the home network anchor (with FM-DP) to
			the new anchor (with FM-DP) to which the MN is
			currently attached. The new anchor will then
			advertise routes for the delegated prefix.
			With a distributed routing protocol, the updates
			spread out from neighbors to neighbors and will affect
			all the forwarding switches such that the packets sent
			from "any" node to MN will go to the new AR.
			Yet the scope of such updates for a given flow may be
			confined to only those forwarding switches such that
			the packets sent only from the "CN" to MN will go to
			the new AR. Such confinement may be made when using a
			centralized central plane possessing a global view of
			all the forwarding switches.
			FM-path-tbl:5 FM reverts the changes previously made to the
			forwarding path of a flow when such changes are no
			longer needed, e.g., when all the ongoing flows using
			an IP prefix/address requiring session continuity have
			closed. When using DHCPv6-PD, the forwarding paths
			will be reverted upon expiration of DHCPv6-PD.
			FM-path-ind:6 Indirection forwards the incoming packets of the flow
			from the DPA at the far end to a DPA/DPN at the near
			end of indirection. Both ends of the indirection
			needs to know the LM information of the MN for the
			flow and also needs to possess FM capability to
			perform indirection.
			FM-path-ind:7 The mechanism of changing the forwarding path in
			[RFC6275] and [RFC5213] is tunneling. In the control
			plane, the FM-CP sets up the tunnel by instructing the
			FM-DP at both ends of the tunnel. In the data plane,
			the FM-DP at the start of the tunnel performs packet
			encapsulation, whereas the FM-DP at the end of the
			tunnel decapsulates the packet.
			Note that in principle the ends of the indirection
			path can be any pair of network elements with the FM-
			DP function.
			FM-path-ind:8 FM reverts the changes previously made to the
			forwarding path of a flow when such changes are no
			longer needed, e.g., when all the ongoing flows using
			an IP prefix/address requiring session continuity have
			closed. When tunneling is used, the tunnels will be
			torn down when they are no longer needed.
			FM-DPA:1 Recall from above that for the incoming packets from the
			CN, forwarding path change by FM is from the DPA at the far
			end which may be at any forwarding switch (or even CN
			itself) in the original forwarding path to the near end
			DPA/DPN.
			It is necessary that any incoming packet from the CN of the
			flow must traverse the DPA (or at least one of the DPAs,
			e.g., in the case of anycast) at the far end in order for
			the packet to detour to a new forwarding path.
			Therefore a convenient design is to locate the far end DPA
			at a unique location which is always in the forwarding
			path. This is the case in a centralized mobility design
			where the DPA at the far end is the home network anchor of
			the flow.
			Distributed mobility however may place the far end DPA at
			other locations in order to avoid unnecessarily long route.
			FM-DPA:2 With multiple nodes possessing DPA capabilities, the role
			of FM to begin path change for the incoming packets of a
			flow at the home network DPA at the far end may be passed
			to or added to that of another DPA.
			In particular, this DPA role may be moved upstream from the
			home network DPA in the original forwarding path from CN to
			MN.
			FM-DPA:3 Optimization of the new forwarding path may be achieved
			when the path change for the incoming packets begins at a
			DPA where the original path and the direct IPv6 path
			overlaps. Then the new forwarding path will resemble the
			direct IPv6 path from the CN to the MN.
			FM-DPA-tbl:4 Forwarding table updates, such as that triggered using
			DHCPv6-PD prefix delegation to change the role of IP
			anchoring from the home network anchor (DPA with FM-DP)
			to the new anchor (DPA with FM-DP), may put the near
			end of the path change at the new DPA. Subsequent
			forwarding table updates may propagates upstream up to
			a far end where the original path and the direct IPv6
			path overlaps.
			When that far end is too far upstream the signaling of
			forwarding table updates may become excessive. An
			alternative is to use indirection (see FM-DPA-ind) from
			that far end to the new DPA at the near end.
			Still another alternative is to combine forwarding
			table update with indirection.
			FM-DPA-tbl:5 Changes made by FM to the following tables, which are
			IPv6 nodes, at the ends of the path change for a flow
			will be reverted when the mobility support for the flow
			is no longer needed, e.g., when the flows have
			terminated.
			FM-DPA-ind:6 With indirection, locating or moving the FM function to
			begin indirection upstream along the forwarding path
			from CN to MN again may help to reduce unnecessarily
			long path.
			FM-DPA-ind:7 Changes made by FM to establish indirection at the DPA
			and DPN, which are IPv6 nodes, at the ends of the path
			change for a flow will be reverted when the mobility
			support for the flow is no longer needed, e.g., when
			the flows have terminated.
			FM-state:1 In addition to the above, a flow/session may contain
			states with the required information for QoS, charging,
			etc. as needed. These states need to be transferred from
			the old anchor to the new anchor.
			FM-buffer:1 An anchor can buffer packets of a flow in a mobility
			event:
			FM-buffer:2 CPA/FM-CP informs DPA/FM-DP to buffer packets of a flow.
			Trigger:
			MN leaves DPA in a mobility event.
			Parameters:
			IP prefix of the flow for which packets need to be
			buffered.
			FM-buffer:3 CPA/FM-CP on behalf of a new DPA/FM-DP informs the CPA/
			FM-CP of the prior DPA/FM-DP that it is ready to receive
			any buffered packets of a flow.
			Parameters:
			destination IP prefix of the flow's packets;
			IP address of the new DPA.
			FM-nemo:1 When the MN is a mobile router the access router anchoring
			the IP prefix of MR will also anchor the IP prefix or
			prefixes delegated to the MR.
			4. IP Mobility Handling in Distributed Anchoring Environments -
			Mobility Support Only When Needed
			IP Mobility Support Only When Needed:
	IP mobility support may be provided only when needed instead of being		IP mobility support may be provided only when needed instead of being
	provided by default. The simplest configuration in this case is		provided by default. The LM and FM functions in the different
	shown in Figures 1(a) and 1(b) in Section 3.1 for which the LM and FM		configurations shown in Section 3.1 are then utilized only when
	functions are utilized only when needed.		needed.
	A straightforward choice of mobility anchoring is for a flow to use		A straightforward choice of mobility anchoring is for a flow to use
	the IP prefix of the network to which the MN is attached when the		the IP prefix of the network to which the MN is attached when the
	flow is initiated [I-D.seite-dmm-dma].		flow is initiated [I-D.seite-dmm-dma].
	4.1.1. Not needed: Changing to the new IP prefix/address		The IP prefix/address at the MN's side of a flow may be anchored at
			the access router to which the MN is attached. For example, when an
			MN attaches to a network (Net1) or moves to a new network (Net2), it
			is allocated an IP prefix from the attached network. In addition to
			configuring new link-local addresses, the MN configures from this
			prefix an IP address which is typically a dynamic IP address. It
			then uses this IP address when a flow is initiated. Packets to the
			MN in this flow are simply forwarded according to the forwarding
			table.
			There may be multiple IP prefixes/addresses that an MN can select
			when initiating a flow. They may be from the same access network or
			different access networks. The network may advertise these prefixes
			with cost options [I-D.mccann-dmm-prefixcost] so that the mobile node
			may choose the one with the least cost. In addition, these IP
			prefixes/addresses may be of different types regarding whether
			mobility support is needed [I-D.ietf-dmm-ondemand-mobility]. A flow
			will need to choose the appropriate one according to whether it needs
			IP mobility support.
			4.1. No Need of IP Mobility: Changing to New IP Prefix/Address
	When IP mobility support is not needed for a flow, the LM and FM		When IP mobility support is not needed for a flow, the LM and FM
	functions are not utilized so that the configuration from Figures		functions are not utilized so that the configurations in Section 3.1
	1(a) and 1(b) in Section 3.1 simplifies to that shown in Figure 3.		are simplified as shown in Figure 4.
	Net1 Net2		Net1 Net2
	+---------------+ +---------------+		+---------------+ +---------------+
	|AR1 | |AR2 |		|AR1 | |AR2 |
	+---------------+ +---------------+		+---------------+ +---------------+
	|CPA: | |CPA: |		|CPA: | |CPA: |
	|---------------| |---------------|		|---------------| |---------------|
	|DPA(IPa1): | |DPA(IPa2): |		|DPA(IPa1): | |DPA(IPa2): |
	|anchors IP1 | |anchors IP2 |		|anchors IP1 | |anchors IP2 |
	+---------------+ +---------------+		+---------------+ +---------------+
	+...............+ +---------------+		+...............+ +---------------+
	.MN(IP1) . move |MN(IP2) |		.MN(IP1) . move |MN(IP2) |
	.flow(IP1,...) . =======> |flow(IP2,...) |		.flow(IP1,...) . =======> |flow(IP2,...) |
	+...............+ +---------------+		+...............+ +---------------+
	Figure 3. Changing to the new IP prefix/address. MN running a flow		Figure 4. Changing to the new IP prefix/address. MN running a flow
	using IP1 in Net1 changes to running a flow using IP2 in Net2.		using IP1 in a network Net1 changes to running a flow using IP2 in
			Net2.
	When there is no need to provide IP mobility to a flow, the flow may		When there is no need to provide IP mobility to a flow, the flow may
	use a new IP address acquired from a new network as the MN moves to		use a new IP address acquired from a new network as the MN moves to
	the new network.		the new network.
	Regardless of whether IP mobility is needed, if the flow has		Regardless of whether IP mobility is needed, if the flow has
	terminated before the MN moves to a new network, the flow may		terminated before the MN moves to a new network, the flow may
	subsequently restart using the new IP address allocated from the new		subsequently restart using the new IP address allocated from the new
	network.		network.
	When session continuity is needed, even if a flow is ongoing as the		When session continuity is needed, even if a flow is ongoing as the
	MN moves, it may still be desirable for the flow to change to using		MN moves, it may still be desirable for the flow to change to using
	the new IP prefix configured in the new network. The flow may then		the new IP prefix configured in the new network. The flow may then
	close and then restart using a new IP address configured in the new		close and then restart using a new IP address configured in the new
	network. Such a change in the IP address of the flow may be enabled		network. Such a change in the IP address of the flow may be enabled
	using a higher layer mobility support which is not in the scope of		using a higher layer mobility support which is not in the scope of
	this document.		this document.
	In Figure 3, a flow initiated while the MN was in Net1 has terminated		In Figure 4, a flow initiated while the MN was in a network Net1 has
	before the MN moves to a new network Net2. After moving to Net2, the		terminated before the MN moves to a new network Net2. After moving
	MN uses the new IP prefix anchored in Net2 to start a new flow. The		to Net2, the MN uses the new IP prefix anchored in Net2 to start a
	packets may then be forwarded without requiring IP layer mobility		new flow. The packets may then be forwarded without requiring IP
	support.		layer mobility support.
	The call flow is outlined in Figure 4.		An example call flow is outlined in Figure 5.
	MN p-AR n-AR CN		MN p-AR n-AR CN
	|MN attaches to p-AR: | | |		|MN attaches to p-AR: | | |
	|acquire MN-ID and profile | |		|acquire MN-ID and profile | |
	|--RS---------------->| | |		|--RS---------------->| | |
	| | | |		| | | |
	|<----------RA(HNP1)--| | |		|<----------RA(HNP1)--| | |
	| | | |		| | | |
	Allocated prefix HNP1		Allocated prefix HNP1
	IP1 address configuration		IP1 address configuration
	skipping to change at page 14, line 32 ¶		skipping to change at page 24, line 30 ¶
	|--RS------------------------------>| |		|--RS------------------------------>| |
	| | | |		| | | |
	|<--------------RA(HNP2)------------| |		|<--------------RA(HNP2)------------| |
	| | | |		| | | |
	Allocated prefix HNP2		Allocated prefix HNP2
	IP2 address configuration		IP2 address configuration
	| | | |		| | | |
	|<-new Flow(IP2,IPcn,...)-----------+------------------------------->|		|<-new Flow(IP2,IPcn,...)-----------+------------------------------->|
	| | | |		| | | |
	Figure 4. A flow uses the IP allocated from the network at which the		Figure 5. Re-starting a flow to use the IP allocated from the
	MN is attached when the flow is initiated.		network at which the MN is attached.
	The security management function in the anchor node at a new network		The security management function in the anchor node at a new network
	must allow to assign a valid IP prefix/address to a mobile node.		must allow to assign a valid IP prefix/address to a mobile node.
	4.1.2. Needed: Providing IP mobility support		4.1.1. Guidelines for IPv6 Nodes: Changing to New IP Prefix/Address
			A network or network slice may not need IP mobility support. For
			example, a network slice for stationary sensors only will never
			encounter mobility.
			The standard functions in IPv6 already include dropping the old IPv6
			prefix/address and acquiring new IPv6 prefix/address when the node
			changes its point of attachment to a new network. Therefore, a
			network or network slice not providing IP mobility support at all
			will not need any of the functions with the mobility behaviors and
			messages described in Section 3.2.
			The guidelines for the IPv6 nodes in a network or network slice
			supporting a mix of flows requiring and not requiring IP mobility
			support include the following:
			GL-cfg:1 A network or network slice supporting a mix of flows
			requiring and not requiring mobility support may take any
			of the configurations described in Section 3.1 and need to
			implement in the appropriate IPv6 nodes the mobility
			functions LM and FM as described respectively in LM-cfg and
			FM-cfg in Section 3.2 according to the configuration
			chosen.
			GL-mix:1 These mobility functions possess some of the behaviors and
			messages described in Section 3.2 depending on which
			mobility mechanisms are used. Yet these mobility functions
			must not be invoked for a flow that does not need IP
			mobility support. It is necessary to be able to
			distinguish the needs of a flow. The guidelines for the MN
			and the AR are in the following.
			GL-mix:2 Regardless of whether there are flows requiring IP mobility
			support, when the MN changes its point of attachment to a
			new network, it needs to configure a new global IP address
			for use in the new network in addition to configuring the
			new link-local addresses.
			GL-mix:3 The MN needs to check whether a flow needs IP mobility
			support. This can be performed when the application was
			initiated. The specific method is not in the scope of this
			document.
			GL-mix:4 The information of whether a flow needs IP mobility support
			is conveyed to the network such as by choosing an IP
			address to be provided with mobility support as described
			in [I-D.ietf-dmm-ondemand-mobility]. Then as the MN
			attaches to a new network, if the MN was using an IP
			address that is not supposed to be provided with mobility
			support, the access router will not invoke the mobility
			functions described in Section 3.2 for this IP address.
			That is, the IP address from the prior network is simply
			not used in the new network.
			The above guidelines are only to enable distinguishing whether there
			is need of IP mobility support for a flow that does not. When the
			flow needs IP mobility support, the list of guidelines will continue
			in Section 4.2.1.
			4.2. Need of IP Mobility
	When IP mobility is needed for a flow, the LM and FM functions in		When IP mobility is needed for a flow, the LM and FM functions in
	Figures 1(a) and 1(b) in Section 3.1 are utilized. The mobility		Section 3.1 are utilized. The mobility support may be provided by IP
	support may be provided by IP prefix anchor switching to the new		prefix anchor switching to the new network to be described in
	network to be described in Section 4.2 or by using other mobility		Section 5 or by using other mobility management methods
	management methods ([Paper-Distributed.Mobility.PMIP] and		([Paper-Distributed.Mobility.PMIP] and
	[Paper-Distributed.Mobility.Review]). Then the flow may continue to		[Paper-Distributed.Mobility.Review]). Then the flow may continue to
	use the IP prefix from the prior network. Yet some time later, the		use the IP prefix from the prior network of attachment. Yet some
	user application for the flow may be closed. If the application is		time later, the user application for the flow may be closed. If the
	started again, the new flow may not need to use the prior network's		application is started again, the new flow may not need to use the
	IP address to avoid having to invoke IP mobility support. This may		prior network's IP address to avoid having to invoke IP mobility
	be the case where a permanent IP prefix/address is not used. The		support. This may be the case where a dynamic IP prefix/address
	flow may then use the new IP prefix in the network where the flow is		rather than a permanent one is used. The flow may then use the new
	being initiated. Routing is again kept simpler without employing IP		IP prefix in the network where the flow is being initiated. Routing
	mobility and will remain so as long as the MN has not moved away from		is again kept simpler without employing IP mobility and will remain
	that network.		so as long as the MN which is now in the new network has not moved
			again and left to another new network.
	The call flow in this case is outlined in Figure 5.		An example call flow in this case is outlined in Figure 6.
	MN p-AR n-AR CN		MN p-AR n-AR CN
	|MN attaches to p-AR: | | |		|MN attaches to p-AR: | | |
	|acquire MN-ID and profile | |		|acquire MN-ID and profile | |
	|--RS---------------->| | |		|--RS---------------->| | |
	| | | |		| | | |
	|<----------RA(HNP1)--| | |		|<----------RA(HNP1)--| | |
	| | | |		| | | |
	Allocated prefix HNP1		Allocated prefix HNP1
	IP1 address configuration		IP1 address configuration
	skipping to change at page 15, line 35 ¶		skipping to change at page 27, line 30 ¶
	|--RS------------------------------>| |		|--RS------------------------------>| |
	IP mobility support such as that described in next sub-section		IP mobility support such as that described in next sub-section
	|<--------------RA(HNP2,HNP1)-------| |		|<--------------RA(HNP2,HNP1)-------| |
	| | | |		| | | |
	|<-Flow(IP1,IPcn,...)---------------+------------------------------->|		|<-Flow(IP1,IPcn,...)---------------+------------------------------->|
	| | | |		| | | |
	Allocated prefix HNP2		Allocated prefix HNP2
	IP2 address configuration		IP2 address configuration
	| | | |		| | | |
	Flow(IP1,IPcn) teminates		Flow(IP1,IPcn) terminates
	| | | |		| | | |
	|<-new Flow(IP2,IPcn,...)-----------+------------------------------->|		|<-new Flow(IP2,IPcn,...)-----------+------------------------------->|
	| | | |		| | | |
	Figure 5. A flow uses the IP allocated from the network at which the		Figure 6. A flow continues to use the IP from its home network after
	MN is attached when the flow is initiated.		MN has moved to a new network.
	To provide IP mobility support with distributed anchoring, the		4.2.1. Guidelines for IPv6 Nodes: Need of IP Mobility
	distributed anchors may need to message with each other. When such
	messaging is needed, the anchors may need to discover each other as
	described in the FM behaviors and information elements (FM:4) in
	Section 3.2.2.
	Then the anchors need to properly forward the packets of the flows as		The configuration guidelines of distributed mobility for the IPv6
	described in the FM behaviors and information elements (FM:3) in		nodes in a network or network slice supporting a mix of flows
	Section 3.2.2.		requiring and not requiring distributed mobility support are as
			follows:
	If there are in-flight packets toward the old anchor while the MN is		GL-cfg:2 Multiple instances of DPAs (at access routers) which are
	moving to the new anchor, it may be necessary to buffer these packets		providing IP prefix to the MNs are needed to provide
	and then forward to the new anchor after the old anchor knows that		distributed anchoring in an appropriate configuration such
	the new anchor is ready. Such are described in the FM behaviors and		as those in Figure 1 (Section 3.1.1) for network-based
	information elements (FM:6) in Section 3.2.2.		distributed mobility or in Figure 3 (Section 3.1.3) for
			host-based distributed mobility.
	4.2. IP prefix/address anchor switching to the new network		The appropriate IPv6 nodes (CPA, DPA, CPN, DPN) are to be
			implemented the mobility functions LM and FM as described
			respectively in LM-cfg and FM-cfg in Section 3.2 according
			to the configuration chosen.
			The guidelines of distributed mobility for the IPv6 nodes in a
			network or network slice supporting a mix of flows requiring and not
			requiring distributed mobility support had begun with those given as
			GL-mix in Section 4.1.1 and continue as follows:
			GL-mix:5 The distributed anchors may need to message with each
			other. When such messaging is needed, the anchors may need
			to discover each other as described in the FM behaviors and
			mobility message parameters (FM-find) in Section 3.2.2.
			GL-mix:6 The anchors may need to provide mobility support on a per-
			flow basis as described in the FM behaviors and mobility
			message parameters (FM-flow) in Section 3.2.2.
			GL-mix:7 Then the anchors need to properly forward the packets of
			the flows as described in the FM behaviors and mobility
			message parameters (FM-path, FM-path-tbl, FM-DPA, FM-DPA-
			tbl) in Section 3.2.2.
			GL-mix:8 If there are in-flight packets toward the old anchor while
			the MN is moving to the new anchor, it may be necessary to
			buffer these packets and then forward to the new anchor
			after the old anchor knows that the new anchor is ready.
			Such are described in the FM behaviors and mobility message
			parameters (FM-buffer) in Section 3.2.2.
			5. IP Mobility Handling in Distributed Anchoring Environments - Anchor
			Switching to the New Network
			IP Prefix/Address Anchor Switching to the New Network:
			IP mobility is invoked to enable session continuity for an ongoing
			flow as the MN moves to a new network. Here the anchoring of the IP
			address of the flow is in the home network of the flow, which is not
			in the current network of attachment. A centralized mobility
			management mechanism may employ indirection from the anchor in the
			home network to the current network of attachment. Yet it may be
			difficult to avoid unnecessarily long route when the route between
			the MN and the CN via the anchor in the home network is too much
			longer than the direct route between them. An alternative is to
			switch the IP prefix/address anchoring to the new network.
			5.1. IP Prefix/Address Anchor Switching for Flat Network
	The IP prefix/address anchoring may move without changing the IP		The IP prefix/address anchoring may move without changing the IP
	prefix/address of the flow. Here the LM and FM functions in Figures		prefix/address of the flow. Here the LM and FM functions in Figures
	1(a) and 1(b) in Section 3.1 are implemented as shown in Figure 6.		1(a) and 1(b) in Section 3.1 are implemented as shown in Figure 7.
	Net1 Net2		Net1 Net2
	+---------------+ +---------------+		+---------------+ +---------------+
	|AR1 | |AR2 |		|AR1 | |AR2 |
	+---------------+ +---------------+		+---------------+ +---------------+
	|CPA: | |CPA: |		|CPA: | |CPA: |
	|LM:IP1<-->IPa2 | |LM:IP1<-->IPa2 |		|LM:IP1<-->IPa2 | |LM:IP1<-->IPa2 |
	|---------------| |---------------|		|---------------| |---------------|
	|DPA(IPa1): | |DPA(IPa2): |		|DPA(IPa1): | |DPA(IPa2): |
	|anchors IP1 | move |anchors IP2,IP1|		|anchors IP1 | move |anchors IP2,IP1|
	|FM:DHCPv6-PD | =======> |FM:DHCPv6-PD |		|FM:DHCPv6-PD | =======> |FM:DHCPv6-PD |
	+---------------+ +---------------+		+---------------+ +---------------+
	+...............+ +---------------+		+...............+ +---------------+
	.MN(IP1) . move |MN(IP2,IP1) |		.MN(IP1) . move |MN(IP2,IP1) |
	.flow(IP1,...) . =======> |flow(IP1,...) |		.flow(IP1,...) . =======> |flow(IP1,...) |
	+...............+ +---------------+		+...............+ +---------------+
	Figure 6. IP prefix/address anchor switching to the new network. MN		Figure 7. IP prefix/address anchor switching to the new network. MN
	with flow using IP1 in Net1 continues to run the flow using IP1 as it		with flow using IP1 in Net1 continues to run the flow using IP1 as it
	moves to Net2.		moves to Net2.
	As an MN with an ongoing session moves to a new network, the flow may		As an MN with an ongoing session moves to a new network, the flow may
	preserve session continuity by moving the anchoring of the original		preserve session continuity by moving the anchoring of the original
	IP prefix/address of the flow to the new network. An example is in		IP prefix/address of the flow to the new network. An example is in
	the use of BGP UPDATE messages to change the forwarding table entries		the use of BGP UPDATE messages to change the forwarding table entries
	as described in [I-D.mccann-dmm-flatarch] and also for 3GPP Evolved		as described in [I-D.mccann-dmm-flatarch] and also for 3GPP Evolved
	Packet Core (EPC) network in [I-D.matsushima-stateless-uplane-vepc].		Packet Core (EPC) network in [I-D.matsushima-stateless-uplane-vepc].
	However, the response time and scalability of using a distributed		However, the response time and scalability of using a distributed
	skipping to change at page 17, line 4 ¶		skipping to change at page 29, line 41 ¶
	moves to Net2.		moves to Net2.
	As an MN with an ongoing session moves to a new network, the flow may		As an MN with an ongoing session moves to a new network, the flow may
	preserve session continuity by moving the anchoring of the original		preserve session continuity by moving the anchoring of the original
	IP prefix/address of the flow to the new network. An example is in		IP prefix/address of the flow to the new network. An example is in
	the use of BGP UPDATE messages to change the forwarding table entries		the use of BGP UPDATE messages to change the forwarding table entries
	as described in [I-D.mccann-dmm-flatarch] and also for 3GPP Evolved		as described in [I-D.mccann-dmm-flatarch] and also for 3GPP Evolved
	Packet Core (EPC) network in [I-D.matsushima-stateless-uplane-vepc].		Packet Core (EPC) network in [I-D.matsushima-stateless-uplane-vepc].
	However, the response time and scalability of using a distributed		However, the response time and scalability of using a distributed
	routing protocol to update forwarding tables may be controversial.		routing protocol to update forwarding tables may be controversial.
	Use of a centralized routing protocol with a centralized control		Use of a centralized routing protocol with a centralized control
	plane as described in Section 4.2.1 will be more scalable.		plane as described in Section 5.2 will be more scalable.
	The location management provides information about which IP prefix		5.1.1. Guidelines for IPv6 Nodes: Switching Anchor for Flat Network
	from an AR in the original network is being used by a flow in which
	AR in a new network. Such information needs to be deleted or updated
	when such flows have closed so that the IP prefix is no longer used
	in a different network. The LM behaviors are described in
	Section 3.2.1.
	The FM functions are implemented through the DHCPv6-PD protocol.		The configuration guideline for a flat network or network slice
	Here the anchor behavior to properly forward the packets for a flow		supporting a mix of flows requiring and not requiring IP mobility
	as described in the FM behaviors and information elements FM:3 in		support is:
	Section 3.2.2 is realized by changing the anchor with DHCPv6-PD and
	also by reverting such changes later after the application has
	already closed and when the DHCPv6-PD timer expires. If there are
	in-flight packets toward the old anchor while the MN is moving to the
	new anchor, it may be necessary to buffer these packets and then
	forward to the new anchor after the old anchor knows that the new
	anchor is ready. Such are described in the FM behaviors and
	information elements FM:6 in Section 3.2.2. The anchors may also
	need to discover each other as described in the FM behaviors and
	information elements FM:4.
	The security management function in the anchor node at a new network		GL-cfg:3 Multiple instances of DPAs (at access routers) which are
	must allow to assign the original IP prefix/address used by the		providing IP prefix to the MNs are needed to provide
	mobile node at the previous (original) network. As the assigned		distributed anchoring according to Figure 1(a) or
	original IP prefix/address is to be used in the new network, the		Figure 1(b)in Section 3.1 for a flat network.
	security management function in the anchor node must allow to
	advertise the prefix of the original IP address and also allow the
	mobile node to send and receive data packets with the original IP
	address.
	The security management function in the mobile node must allow to		The appropriate IPv6 nodes (CPA, DPA) are to be implemented
	configure the original IP prefix/address used at the previous		the mobility functions LM and FM as described respectively
	(original) network when the original IP prefix/address is assigned by		in LM-cfg:1 or LM-cfg:2 and FM-cfg:1 in Section 3.2.
	the anchor node in the new network. The security management function
	in the mobile node also allows to use the original IP address for the
	previous flow in the new network.
	4.2.1. Centralized control plane		The guidelines (GL-mix) in Section 4.1.1 and in Section 4.2.1 for the
			IPv6 nodes for a network or network slice supporting a mix of flows
			requiring and not requiring IP mobility support apply here. In
			addition, the following are required.
			GL-switch:1 The location management provides information about which
			IP prefix from an AR in the original network is being
			used by a flow in which AR in a new network. Such
			information needs to be deleted or updated when such
			flows have closed so that the IP prefix is no longer
			used in a different network. The LM behaviors are
			described in Section 3.2.1.
			GL-switch:2 The FM functions are implemented through the DHCPv6-PD
			protocol. Here the anchor behaviors to properly forward
			the packets for a flow as described in the FM behaviors
			and mobility message parameters in Section 3.2.2 FM-
			path, FM-path-tbl, FM-DPA, FM-DPA-tbl are realized by
			changing the anchor with DHCPv6-PD and also by reverting
			such changes later after the application has already
			closed and when the DHCPv6-PD timer expires. If there
			are in-flight packets toward the old anchor while the MN
			is moving to the new anchor, it may be necessary to
			buffer these packets and then forward to the new anchor
			after the old anchor knows that the new anchor is ready.
			Such are described in the FM behaviors and mobility
			message parameters in Section 3.2.2 FM-buffer. The
			anchors may also need to discover each other as
			described also in the FM behaviors and mobility message
			parameters (FM-find).
			GL-switch:3 The security management function in the anchor node at a
			new network must allow to assign the original IP prefix/
			address used by the mobile node at the previous
			(original) network. As the assigned original IP prefix/
			address is to be used in the new network, the security
			management function in the anchor node must allow to
			advertise the prefix of the original IP address and also
			allow the mobile node to send and receive data packets
			with the original IP address.
			GL-switch:4 The security management function in the mobile node must
			allow to configure the original IP prefix/address used
			at the previous (original) network when the original IP
			prefix/address is assigned by the anchor node in the new
			network. The security management function in the mobile
			node also allows to use the original IP address for the
			previous flow in the new network.
			5.2. IP Prefix/Address Anchor Switching for Flat Network with
			Centralized Control Plane
	An example of IP prefix anchor switching is in the case where Net1		An example of IP prefix anchor switching is in the case where Net1
	and Net2 both belong to the same operator network with separation of		and Net2 both belong to the same operator network with separation of
	control and data planes ([I-D.liu-dmm-deployment-scenario] and		control and data planes ([I-D.liu-dmm-deployment-scenario] and
	[I-D.matsushima-stateless-uplane-vepc]), where the controller may		[I-D.matsushima-stateless-uplane-vepc]), where the controller may
	send to the switches/routers the updated information of the		send to the switches/routers the updated information of the
	forwarding tables with the IP address anchoring of the original IP		forwarding tables with the IP address anchoring of the original IP
	prefix/address at AR1 moved to AR2 in the new network. That is, the		prefix/address at AR1 moved to AR2 in the new network. That is, the
	IP address anchoring in the original network which was advertising		IP address anchoring in the original network which was advertising
	the prefix will need to move to the new network. As the anchoring in		the prefix will need to move to the new network. As the anchoring in
	the new network advertises the prefix of the original IP address in		the new network advertises the prefix of the original IP address in
	the new network, the forwarding tables will be updated so that		the new network, the forwarding tables will be updated so that
	packets of the flow will be forwarded according to the updated		packets of the flow will be forwarded according to the updated
	forwarding tables. The configuration in Figures 1(a) and 1(b) in		forwarding tables. The configurations in Figures 1(a) and 1(b) in
	Section 3.1 for which FM-CP and LM are centralized and FM-DP's are		Section 3.1 for which FM-CP and LM are centralized and FM-DP's are
	distributed. applies here. Figure 7 shows its implementation where		distributed apply here. Figure 8 shows its implementation where LM
	LM is a binding between the original IP prefix/address of the flow		is a binding between the original IP prefix/address of the flow and
	and the IP address of the new DPA, whereas FM uses the DHCPv6-PD		the IP address of the new DPA, whereas FM uses the DHCPv6-PD
	protocol.		protocol.
	Net1 Net2		Net1 Net2
	+----------------------------------------------------------------------+		+----------------------------------------------------------------------+
	| CPA: |		| CPA: |
	| LM:IP1<-->IPa2 |		| LM:IP1<-->IPa2 |
	| FM-CP |		| FM-CP |
	+----------------------------------------------------------------------+		+----------------------------------------------------------------------+
	+---------------+ +---------------+		+---------------+ +---------------+
	skipping to change at page 18, line 37 ¶		skipping to change at page 32, line 25 ¶
	|DPA(IPa1): | |DPA(IPa2): |		|DPA(IPa1): | |DPA(IPa2): |
	|anchors IP1 | move |anchors IP2,IP1|		|anchors IP1 | move |anchors IP2,IP1|
	|FM:DHCPv6-PD | =======> |FM:DHCPv6-PD |		|FM:DHCPv6-PD | =======> |FM:DHCPv6-PD |
	+---------------+ +---------------+		+---------------+ +---------------+
	+...............+ +---------------+		+...............+ +---------------+
	.MN(IP1) . move |MN(IP2,IP1) |		.MN(IP1) . move |MN(IP2,IP1) |
	.flow(IP1,...) . =======> |flow(IP1,...) |		.flow(IP1,...) . =======> |flow(IP1,...) |
	+...............+ +---------------+		+...............+ +---------------+
	Figure 7. IP prefix/address anchor switching to the new network with		Figure 8. IP prefix/address anchor switching to the new network with
	with LM and FM-CP in a centralized control plane whereas the FM-DP's		with LM and FM-CP in a centralized control plane whereas the FM-DP's
	are distributed.		are distributed.
	The call flow in Figure 8 shows that MN is allocated HNP1 when it		The example call flow in Figure 9 shows that MN is allocated HNP1
	attaches to the p-AR. A flow running in MN may or may not need IP		when it attaches to the p-AR. A flow running in MN and needing IP
	mobility. If it does, it may continue to use the previous IP prefix.		mobility may continue to use the previous IP prefix by moving the
	If it does not, it may use a new IP prefix allocated from the new		anchoring of the IP prefix to the new network. Yet a new flow to be
	network.		initiated in the new network may simply use a new IP prefix allocated
			from the new network.
	MN p-AR n-AR DHCP Servers CN		MN p-AR n-AR DHCP Servers CN
	|MN attaches to p-AR: | | | |		|MN attaches to p-AR: | | | |
	|acquire MN-ID and profile | | |		|acquire MN-ID and profile | | |
	|--RS---------------->| | | |		|--RS---------------->| | | |
	|<----------RA(HNP1)--| | | |		|<----------RA(HNP1)--| | | |
	| | | Allocate MN-HNP1 |		| | | Allocate MN-HNP1 |
	IP addr config | | | |		IP addr config | | | |
	| | | | |		| | | | |
	|<-Flow(IP1,IPcn,...)-+--------------------------------------------->|		|<-Flow(IP1,IPcn,...)-+--------------------------------------------->|
	skipping to change at page 19, line 43 ¶		skipping to change at page 33, line 43 ¶
	| Flow(IP1,IPcn,...) terminates | | |		| Flow(IP1,IPcn,...) terminates | | |
	| | | | |		| | | | |
	| | DHCPv6-PD timeout | |		| | DHCPv6-PD timeout | |
	| | | | |		| | | | |
	| forwarding table updates | |		| forwarding table updates | |
	| | | | |		| | | | |
	| | | | |		| | | | |
	|<-new Flow(IP2,IPcn,...)-----------+------------------------------->|		|<-new Flow(IP2,IPcn,...)-----------+------------------------------->|
	| | | | |		| | | | |
	Figure 8. DMM solution. MN with flow using IP1 in Net1 continues to		Figure 9. DMM solution. MN with flow using IP1 in Net1 continues to
	run the flow using IP1 as it moves to Net2.		run the flow using IP1 as it moves to Net2.
	As the MN moves from p-AR to n-AR, the p-AR as a DHCP client may send		As the MN moves from p-AR to n-AR, the p-AR as a DHCP client may send
	a DHCP release message to release the HNP1. It is now necessary for		a DHCP release message to release the HNP1. It is now necessary for
	n-AR to learn the IP prefix of the MN from the previous network so		n-AR to learn the IP prefix of the MN from the previous network so
	that it will be possible for Net2 to allocate both the previous		that it will be possible for Net2 to allocate both the previous
	network prefix and the new network prefix. The network may learn the		network prefix and the new network prefix. The network may learn the
	previous prefix in different methods. For example, the MN may		previous prefix in different methods. For example, the MN may
	provide its previous network prefix information by including it to		provide its previous network prefix information by including it to
	the RS message [I-D.jhlee-dmm-dnpp].		the RS message [I-D.jhlee-dmm-dnpp].
	Knowing that MN is using HNP1, the n-AR sends to a DHCP server a		Knowing that MN is using HNP1, the n-AR sends to a DHCP server a
	DHCPv6-PD request to move the HNP1 to n-AR. The server sends to n-AR		DHCPv6-PD request to move the HNP1 to n-AR. The server sends to n-AR
	a DHCPv6-PD reply to move the HNP1. Then BGP route updates will take		a DHCPv6-PD reply to move the HNP1. Then forwarding tables updates
	place here.		will take place here.
	In addition, the MN also needs a new HNP in the new network. The		In addition, the MN also needs a new HNP in the new network. The
	n-AR may now send RA to n-AR, with prefix information that includes		n-AR may now send RA to n-AR, with prefix information that includes
	HNP1 and HNP2. The MN may then continue to use IP1. In addition,		HNP1 and HNP2. The MN may then continue to use IP1. In addition,
	the MN is allocated the prefix HNP2 with which it may configure its		the MN is allocated the prefix HNP2 with which it may configure its
	IP addresses. Now for flows using IP1, packets destined to IP1 will		IP addresses. Now for flows using IP1, packets destined to IP1 will
	be forwarded to the MN via n-AR.		be forwarded to the MN via n-AR.
	As such flows have terminated and DHCP-PD has timed out, HNP1 goes		As such flows have terminated and DHCP-PD has timed out, HNP1 goes
	back to Net1. MN will then be left with HNP2 only, which it will use		back to Net1. MN will then be left with HNP2 only, which it will use
	when it now starts a new flow.		when it now starts a new flow.
	The anchor behavior to properly forward the packets for a flow as		5.2.1. Additional Guidelines for IPv6 Nodes: Switching Anchor with
	described in the FM behaviors and information elements (FM:3) in		Centralized CP
	Section 3.2.2 is realized by changing the anchor with DHCPv6-PD and
	undoing such changes later when its timer expires and the application
	has already closed. With the anchors being separated in control and
	data planes with LMs and FM-CP centralized in the same control plane,
	messaging between anchors and the discovery of anchors become
	internal to the control plane. However, the centralized FM-CP needs
	to communicate with the distributed FM-DP as described as described
	in the FM behaviors and information elements (FM:5). Such may be
	realized by the appropriate messages in [I-D.ietf-dmm-fpc-cpdp].
	Again, if there are in-flight packets toward the old anchor while the
	MN is moving to the new anchor, it may be necessary to buffer these
	packets and then forward to the new anchor after the old anchor knows
	that the new anchor is ready. The corresponding FM behaviors and
	information elements (FM:6) are however realized by the internal
	behavior in the control plane together with signaling between the
	control plane and distributed data plane.
	4.2.2. Hierarchical network		The configuration guideline for a flat network or network slice with
			centralized control plane and supporting a mix of flows requiring and
			not requiring IP mobility support is:
			GL-cfg:4 Multipel instances of DPAs (at access routers) which are
			providing IP prefix to the MNs are needed to provide
			distributed anchoring according to Figure 1(a) or
			Figure 1(b)in Section 3.1 with centralized control plane
			for a flat network.
			The appropriate IPv6 nodes (CPA, DPA) are to be implemented
			the mobility functions LM and FM as described respectively
			in LM-cfg:1 or LM-cfg:2 and FM-cfg:1 in Section 3.2.
			The guidelines (GL-mix) in Section 4.1.1 and in Section 4.2.1 for the
			IPv6 nodes for a network or network slice supporting a mix of flows
			requiring and not requiring IP mobility support apply here. The
			guidelines (GL-mix) in Section 5.1.1 also apply here. In addition,
			the following are required.
			GL-switch:5 The anchor behavior to properly forward the packets for
			a flow as described in the FM behaviors and mobility
			message parameters in Section 3.2.2 FM-path, FM-path-
			tbl, FM-DPA, FM-DPA-tbl is realized by changing the
			anchoring with DHCPv6-PD and undoing such changes later
			when its timer expires and the application has already
			closed. With the anchors being separated in control and
			data planes with LMs and FM-CP centralized in the same
			control plane, messaging between anchors and the
			discovery of anchors become internal to the control
			plane as described in Section 3.2.2 FM-cpdp. However,
			the centralized FM-CP needs to communicate with the
			distributed FM-DP as described as described in the FM
			behaviors and mobility message parameters (FM-find).
			Such may be realized by the appropriate messages in
			[I-D.ietf-dmm-fpc-cpdp].
			GL-switch:6 It was already mentioned before that, if there are in-
			flight packets toward the old anchor while the MN is
			moving to the new anchor, it may be necessary to buffer
			these packets and then forward to the new anchor after
			the old anchor knows that the new anchor is ready Here,
			however, the corresponding FM behaviors and mobility
			message parameters as described in Section 3.2.2 (FM-
			buffer) can be realized by the internal behavior in the
			control plane together with signaling between the
			control plane and distributed data plane. These
			signaling may be realized by the appropriate messages in
			[I-D.ietf-dmm-fpc-cpdp].
			5.3. IP Prefix/Address Anchor Switching for Hierarchical Network
	The configuration for a hierarchical network is shown in Figures 1(c)		The configuration for a hierarchical network is shown in Figures 1(c)
	and 1(d) in Section 3.1. With centralized control and with a		and 1(d) in Section 3.1. With centralized control plane, CPA and
	centralized anchor, LM, CPA, CPN are co-located at the centralized		CPN, with the associated LM and FM-CP are all co-located. There are
	control, and there is an AR with the DPA function supporting multiple		multiple DPAs (each with FM-DP) in distributed mobility anchoring.
	forwarding switches (FW's) each with a DPN function. A mobility		In the data plane, there are multiple DPNs (each with FM-DP)
	event in this configuration involving change of FW but not of AR is		hierarchically below each DPA. The DPA at each AR supports
	shown in Figure 9.		forwarding to the DPN at each of a number of forwarding switches
			(FW's). A mobility event in this configuration belonging to
			distributed mobility management will be deferred to Section 5.4.
	Here the IP prefix allocated to the MN is anchored at the access		In this distributed mobility configuration, a mobility event
	router (AR) supporting the old FW to which the MN was originally		involving change of FW only but not of AR as shown in Figure 10 may
	attached as well as the new FW to which the MN has moved.		still belong to centralized mobility management and may be supported
			using PMIPv6. This configuration of network-based mobility is also
			applicable to host-based mobility with the modification for the MN
			directly taking the role of DPN and CPN, and the corresponding
			centralized mobility event may be supported using MIPv6.
			In Figure 10, the IP prefix allocated to the MN is anchored at the
			access router (AR) supporting indirection to the old FW to which the
			MN was originally attached as well as to the new FW to which the MN
			has moved.
	The realization of LM may be the binding between the IP prefix/		The realization of LM may be the binding between the IP prefix/
	address of the flow used by the MN and the IP address of the DPN to		address of the flow used by the MN and the IP address of the DPN to
	which MN has moved. The implementation of FM to enable change of FW		which MN has moved. The implementation of FM to enable change of FW
	without changing AR may be accomplished using tunneling between the		without changing AR may be accomplished using tunneling between the
	AR and the FW as described in [I-D.korhonen-dmm-local-prefix] and in		AR and the FW as described in [I-D.korhonen-dmm-local-prefix] and in
	[I-D.templin-aerolink] or using some other L2 mobility mechanism.		[I-D.templin-aerolink] or using some other L2 mobility mechanism.
	Net1 Net2		Net1 Net2
	+----------------------------------------------------------------------+		+----------------------------------------------------------------------+
	skipping to change at page 21, line 42 ¶		skipping to change at page 36, line 43 ¶
	|FW1 | |FW2 |		|FW1 | |FW2 |
	+---------------+ move +---------------+		+---------------+ move +---------------+
	|DPN(IPn1): | =======> |DPN(IPn2): |		|DPN(IPn1): | =======> |DPN(IPn2): |
	+---------------+ +---------------+		+---------------+ +---------------+
	+...............+ +---------------+		+...............+ +---------------+
	.MN(IP1) . move |MN(IP2) |		.MN(IP1) . move |MN(IP2) |
	.flow(IP1,...) . =======> |flow(IP1,...) |		.flow(IP1,...) . =======> |flow(IP1,...) |
	+...............+ +---------------+		+...............+ +---------------+
	Figure 9. Mobility without involving change of IP anchoring in a		Figure 10. Mobility without involving change of IP anchoring in a
	network with hierarchy in which the IP prefix allocated to the MN is		network in which the IP prefix allocated to the MN is anchored at an
	anchored at an Edge Router supporting multiple access routers to		AR which is hierarchically above multiple FWs to which the MN may
	which the MN may connect.		connect.
	Here, the LM behaviors and information elements described in		5.3.1. Additional Guidelines for IPv6 Nodes: No Anchoring Change with
	Section 3.2.1 provides information of which IP prefix from its FW		Hierarchical Network
	needs to be used by a flow using which new FW. The anchor behaviors
	to properly forward the packets of a flow described in the FM
	behaviors and information elements (FM:3) may be realized with PMIPv6
	protocol ([I-D.korhonen-dmm-local-prefix]) or with AERO protocol
	([I-D.templin-aerolink]) to tunnel between the AR and the FW.
	4.2.3. Hierarchical network with anchoring change		The configuration guideline ( ) for a hierarchical network or network
			slice with centralized control plane and supporting a mix of flows
			requiring and not requiring IP mobility support is:
	The configuration for a hierarchical network is still shown in		GL-cfg:5 Multipel instances of DPAs (at access routers) which are
	Figures 1(c) and 1(d) in Section 3.1. Again, with centralized		providing IP prefix to the MNs are needed to provide
	control and with a centralized anchor, LM, CPA, CPN are co-located at		distributed anchoring according to Figure 2(a) or
	the centralized control, and there is an AR with the DPA function		Figure 2(b)in Section 3.1.2 with centralized control plane
	supporting multiple forwarding switches (FW's) each with a DPN		for a hierarchical network.
	function. However, the mobility event involving change of FW may
	also involve a change of AR. Such configuration is shown in
	Figure 10.
	This deployment case involves both a change of anchor from AR1 to AR2		The appropriate IPv6 nodes (CPA, DPA) are to be implemented
	and a network hierarchy AR-FW. It can be realized by a combination		the mobility functions LM and FM as described respectively
	of changing the IP prefix/address anchoring from AR1 to AR2 with the		in LM-cfg:3 or LM-cfg:4 and FM-cfg:2 in Section 3.2.
	mechanism as described in Section 4.2.1 and then forwarding the
	packets with network hierarchy AR-FW as described in Section 4.2.2.
	To change AR, AR1 acting as a DHCP-PD client may exchange message		Even when the mobility event does not involve change of anchor, it is
	with the DHCP server to release the prefix IP1. Meanwhile, AR2		still necessary to distinguish whether a flow needs IP mobility
	acting as a DHCP-PD client may exchange message with the DHCP server		support.
	to delegate the prefix IP1 to AR2.
			The GL-mix guidelines in Section 4.1.1 and in Section 4.2.1 for the
			IPv6 nodes for a network or network slice supporting a mix of flows
			requiring and not requiring IP mobility support apply here. The
			guidelines (GL-switch) in Section 5.1.1 and in Section 5.2.1 also
			apply here. In addition, the following are required.
			GL-switch:7 Here, the LM behaviors and mobility message parameters
			described in Section 3.2.1 provides information of which
			IP prefix from its FW needs to be used by a flow using
			which new FW. The anchor behaviors to properly forward
			the packets of a flow described in the FM behaviors and
			mobility message parameters (FM-path, FM-path-ind, FM-
			cpdp in Section 3.2.2) may be realized with PMIPv6
			protocol ([I-D.korhonen-dmm-local-prefix]) or with AERO
			protocol ([I-D.templin-aerolink]) to tunnel between the
			AR and the FW.
			5.4. IP Prefix/Address Anchor Switching for Hierarchical Network
			The configuration for the hierarchical network is again shown in
			Figures 1(c) and 1(d) in Section 3.1. Again, with centralized
			control plane, CPA and CPN, with the associated LM and FM-CP are all
			co-located. There are multiple DPAs (each with FM-DP) in distributed
			mobility anchoring. In the data plane, there are multiple DPNs (each
			with FM-DP) hierarchically below each DPA. The DPA at each AR
			supports forwarding to the DPN at each of a number of forwarding
			switches (FW's).
			A distributed mobility event in this configuration involves change
			from a previous DPN which is hierarchically under the previous DPA to
			a new DPN which is hierarchically under a new DPA. Such an event
			involving change of both DPA and DPN is shown in Figure 11.
	Net1 Net2		Net1 Net2
	+----------------------------------------------------------------------+		+----------------------------------------------------------------------+
	| CPA,CPN: |		| CPA,CPN: |
	| LM:IP1<-->IPa2,IPn2 |		| LM:IP1<-->IPa2,IPn2 |
	| FM-CP |		| FM-CP |
	+----------------------------------------------------------------------+		+----------------------------------------------------------------------+
	+---------------+		+---------------+
	|Aggregate Point|		|Aggregate Point|
	skipping to change at page 23, line 37 ¶		skipping to change at page 38, line 45 ¶
	|FW1 | |FW2 |		|FW1 | |FW2 |
	+---------------+ move +---------------+		+---------------+ move +---------------+
	|DPN(IPn1): | =======> |DPN(IPn2): |		|DPN(IPn1): | =======> |DPN(IPn2): |
	+---------------+ +---------------+		+---------------+ +---------------+
	+...............+ +---------------+		+...............+ +---------------+
	.MN(IP1) . move |MN(IP2,IP1) |		.MN(IP1) . move |MN(IP2,IP1) |
	.flow(IP1,...) . =======> |flow(IP1,...) |		.flow(IP1,...) . =======> |flow(IP1,...) |
	+...............+ +---------------+		+...............+ +---------------+
	Figure 10. Mobility involving change of IP anchoring in a network		Figure 11. Mobility involving change of IP anchoring in a network
	with hierarchy in which the IP prefix allocated to the MN is anchored		with hierarchy in which the IP prefix allocated to the MN is anchored
	at an Edge Router supporting multiple access routers to which the MN		at an Edge Router supporting multiple access routers to which the MN
	may connect.		may connect.
	5. Security Considerations		This deployment case involves both a change of anchor from AR1 to AR2
			and a network hierarchy AR-FW. It can be realized by a combination
			of changing the IP prefix/address anchoring from AR1 to AR2 with the
			mechanism as described in Section 5.2 and then forwarding the packets
			with network hierarchy AR-FW as described in Section 5.3.
			To change AR, AR1 acting as a DHCP-PD client may exchange message
			with the DHCP server to release the prefix IP1. Meanwhile, AR2
			acting as a DHCP-PD client may exchange message with the DHCP server
			to delegate the prefix IP1 to AR2.
			5.4.1. Additional Guidelines for IPv6 Nodes: Switching Anchor with
			Hierarchical Network
			The configuration guideline (GL-cfg) for a hierarchical network or
			network slice with centralized control plane described in
			Section 5.3.1 apply here.
			The GL-mix guidelines in Section 4.1.1 and in Section 4.2.1 for the
			IPv6 nodes for a network or network slice supporting a mix of flows
			requiring and not requiring IP mobility support apply here.
			The guidelines (GL-switch) in Section 5.1.1 and in Section 5.2.1 also
			apply here to change the anchoring of the IP prefix/address with a
			centralized control plane.
			In addition, the guideline for indirection between the new DPA and
			the new DPN as described in Section 5.3.1 apply here.
			6. Security Considerations
	TBD		TBD
	6. IANA Considerations		7. IANA Considerations
	This document presents no IANA considerations.		This document presents no IANA considerations.
	7. Contributors		8. Contributors
	This document has benefited from other work on mobility solutions		This document has benefited from other work on mobility solutions
	using BGP update, on mobility support in SDN network, on providing		using BGP update, on mobility support in SDN network, on providing
	mobility support only when needed, and on mobility support in		mobility support only when needed, and on mobility support in
	enterprise network. These work have been referenced. While some of		enterprise network. These work have been referenced. While some of
	these authors have taken the work to jointly write this document,		these authors have taken the work to jointly write this document,
	others have contributed at least indirectly by writing these drafts.		others have contributed at least indirectly by writing these drafts.
	The latter include Philippe Bertin, Dapeng Liu, Satoru Matushima,		The latter include Philippe Bertin, Dapeng Liu, Satoru Matushima,
	Peter McCann, Pierrick Seite, Jouni Korhonen, and Sri Gundavelli.		Peter McCann, Pierrick Seite, Jouni Korhonen, and Sri Gundavelli.
	Valuable comments have also been received from John Kaippallimil,		Valuable comments have also been received from John Kaippallimalil,
	ChunShan Xiong, and Dapeng Liu.		ChunShan Xiong, and Dapeng Liu.
	8. References		9. References
	8.1. Normative References		9.1. Normative References
			[I-D.ietf-dmm-deployment-models]
			Gundavelli, S. and S. Jeon, "DMM Deployment Models and
			Architectural Considerations", draft-ietf-dmm-deployment-
			models-00 (work in progress), August 2016.
	[I-D.ietf-dmm-fpc-cpdp]		[I-D.ietf-dmm-fpc-cpdp]
	Liebsch, M., Matsushima, S., Gundavelli, S., Moses, D.,		Liebsch, M., Matsushima, S., Gundavelli, S., Moses, D.,
	and L. Bertz, "Protocol for Forwarding Policy		and L. Bertz, "Protocol for Forwarding Policy
	Configuration (FPC) in DMM", draft-ietf-dmm-fpc-cpdp-03		Configuration (FPC) in DMM", draft-ietf-dmm-fpc-cpdp-03
	(work in progress), March 2016.		(work in progress), March 2016.
	[I-D.ietf-dmm-ondemand-mobility]		[I-D.ietf-dmm-ondemand-mobility]
	Yegin, A., Moses, D., Kweon, K., Lee, J., and J. Park, "On		Yegin, A., Moses, D., Kweon, K., Lee, J., and J. Park, "On
	Demand Mobility Management", draft-ietf-dmm-ondemand-		Demand Mobility Management", draft-ietf-dmm-ondemand-
	skipping to change at page 25, line 33 ¶		skipping to change at page 41, line 27 ¶
	Anchoring", draft-seite-dmm-dma-07 (work in progress),		Anchoring", draft-seite-dmm-dma-07 (work in progress),
	February 2014.		February 2014.
	[I-D.sijeon-dmm-deployment-models]		[I-D.sijeon-dmm-deployment-models]
	Jeon, S. and Y. Kim, "Deployment Models for Distributed		Jeon, S. and Y. Kim, "Deployment Models for Distributed
	Mobility Management", draft-sijeon-dmm-deployment-		Mobility Management", draft-sijeon-dmm-deployment-
	models-03 (work in progress), July 2016.		models-03 (work in progress), July 2016.
	[I-D.templin-aerolink]		[I-D.templin-aerolink]
	Templin, F., "Asymmetric Extended Route Optimization		Templin, F., "Asymmetric Extended Route Optimization
	(AERO)", draft-templin-aerolink-70 (work in progress),		(AERO)", draft-templin-aerolink-71 (work in progress),
	July 2016.		September 2016.
	[I-D.wt-dmm-deployment-models]
	Gundavelli, S., "DMM Deployment Models and Architectural
	Considerations", draft-wt-dmm-deployment-models-00 (work
	in progress), April 2016.
	[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate		[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
	Requirement Levels", BCP 14, RFC 2119,		Requirement Levels", BCP 14, RFC 2119,
	DOI 10.17487/RFC2119, March 1997,		DOI 10.17487/RFC2119, March 1997,
	<http://www.rfc-editor.org/info/rfc2119>.		<http://www.rfc-editor.org/info/rfc2119>.
			[RFC3753] Manner, J., Ed. and M. Kojo, Ed., "Mobility Related
			Terminology", RFC 3753, DOI 10.17487/RFC3753, June 2004,
			<http://www.rfc-editor.org/info/rfc3753>.
	[RFC5213] Gundavelli, S., Ed., Leung, K., Devarapalli, V.,		[RFC5213] Gundavelli, S., Ed., Leung, K., Devarapalli, V.,
	Chowdhury, K., and B. Patil, "Proxy Mobile IPv6",		Chowdhury, K., and B. Patil, "Proxy Mobile IPv6",
	RFC 5213, DOI 10.17487/RFC5213, August 2008,		RFC 5213, DOI 10.17487/RFC5213, August 2008,
	<http://www.rfc-editor.org/info/rfc5213>.		<http://www.rfc-editor.org/info/rfc5213>.
	[RFC6275] Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility		[RFC6275] Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility
	Support in IPv6", RFC 6275, DOI 10.17487/RFC6275, July		Support in IPv6", RFC 6275, DOI 10.17487/RFC6275, July
	2011, <http://www.rfc-editor.org/info/rfc6275>.		2011, <http://www.rfc-editor.org/info/rfc6275>.
			[RFC7077] Krishnan, S., Gundavelli, S., Liebsch, M., Yokota, H., and
			J. Korhonen, "Update Notifications for Proxy Mobile IPv6",
			RFC 7077, DOI 10.17487/RFC7077, November 2013,
			<http://www.rfc-editor.org/info/rfc7077>.
	[RFC7333] Chan, H., Ed., Liu, D., Seite, P., Yokota, H., and J.		[RFC7333] Chan, H., Ed., Liu, D., Seite, P., Yokota, H., and J.
	Korhonen, "Requirements for Distributed Mobility		Korhonen, "Requirements for Distributed Mobility
	Management", RFC 7333, DOI 10.17487/RFC7333, August 2014,		Management", RFC 7333, DOI 10.17487/RFC7333, August 2014,
	<http://www.rfc-editor.org/info/rfc7333>.		<http://www.rfc-editor.org/info/rfc7333>.
	[RFC7429] Liu, D., Ed., Zuniga, JC., Ed., Seite, P., Chan, H., and		[RFC7429] Liu, D., Ed., Zuniga, JC., Ed., Seite, P., Chan, H., and
	CJ. Bernardos, "Distributed Mobility Management: Current		CJ. Bernardos, "Distributed Mobility Management: Current
	Practices and Gap Analysis", RFC 7429,		Practices and Gap Analysis", RFC 7429,
	DOI 10.17487/RFC7429, January 2015,		DOI 10.17487/RFC7429, January 2015,
	<http://www.rfc-editor.org/info/rfc7429>.		<http://www.rfc-editor.org/info/rfc7429>.
	8.2. Informative References		9.2. Informative References
	[Paper-Distributed.Mobility]		[Paper-Distributed.Mobility]
	Lee, J., Bonnin, J., Seite, P., and H. Chan, "Distributed		Lee, J., Bonnin, J., Seite, P., and H. Chan, "Distributed
	IP Mobility Management from the Perspective of the IETF:		IP Mobility Management from the Perspective of the IETF:
	Motivations, Requirements, Approaches, Comparison, and		Motivations, Requirements, Approaches, Comparison, and
	Challenges", IEEE Wireless Communications, October 2013.		Challenges", IEEE Wireless Communications, October 2013.
	[Paper-Distributed.Mobility.PMIP]		[Paper-Distributed.Mobility.PMIP]
	Chan, H., "Proxy Mobile IP with Distributed Mobility		Chan, H., "Proxy Mobile IP with Distributed Mobility
	Anchors", Proceedings of GlobeCom Workshop on Seamless		Anchors", Proceedings of GlobeCom Workshop on Seamless
	Wireless Mobility, December 2010.		Wireless Mobility, December 2010.
	[Paper-Distributed.Mobility.Review]		[Paper-Distributed.Mobility.Review]
	Chan, H., Yokota, H., Xie, J., Seite, P., and D. Liu,		Chan, H., Yokota, H., Xie, J., Seite, P., and D. Liu,
	"Distributed and Dynamic Mobility Management in Mobile		"Distributed and Dynamic Mobility Management in Mobile
	Internet: Current Approaches and Issues", February 2011.		Internet: Current Approaches and Issues", February 2011.
	Authors' Addresses		Authors' Addresses
	H Anthony Chan		H Anthony Chan (editor)
	Huawei Technologies		Huawei Technologies
	5340 Legacy Dr. Building 3		5340 Legacy Dr. Building 3
	Plano, TX 75024		Plano, TX 75024
	USA		USA
	Email: h.a.chan@ieee.org		Email: h.a.chan@ieee.org
	Xinpeng Wei		Xinpeng Wei
	Huawei Technologies		Huawei Technologies
	Xin-Xi Rd. No. 3, Haidian District		Xin-Xi Rd. No. 3, Haidian District
	Beijing, 100095		Beijing, 100095
	P. R. China		P. R. China
	Email: weixinpeng@huawei.com		Email: weixinpeng@huawei.com
	Jong-Hyouk Lee		Jong-Hyouk Lee
	Sangmyung University		Sangmyung University
	708 Hannuri Building		31, Sangmyeongdae-gil, Dongnam-gu
	Cheonan 330-720		Cheonan 31066
	Korea		Republic of Korea
	Email: jonghyouk@smu.ac.kr		Email: jonghyouk@smu.ac.kr
	Seil Jeon		Seil Jeon
	Sungkyunkwan University		Sungkyunkwan University
	2066 Seobu-ro, Jangan-gu		2066 Seobu-ro, Jangan-gu
	Suwon, Gyeonggi-do		Suwon, Gyeonggi-do
	Korea		Republic of Korea
	Email: seiljeon@gmail.com		Email: seiljeon@skku.edu
			Alexandre Petrescu
			CEA, LIST
			CEA Saclay
			Gif-sur-Yvette, Ile-de-France 91190
			France
			Phone: +33169089223
			Email: Alexandre.Petrescu@cea.fr
	Fred L. Templin		Fred L. Templin
	Boeing Research and Technology		Boeing Research and Technology
	P.O. Box 3707		P.O. Box 3707
	Seattle, WA 98124		Seattle, WA 98124
	USA		USA
	Email: fltemplin@acm.org		Email: fltemplin@acm.org
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