--- 1/draft-ietf-lisp-rfc6830bis-11.txt 2018-03-19 04:13:37.347388316 -0700 +++ 2/draft-ietf-lisp-rfc6830bis-12.txt 2018-03-19 04:13:37.439390498 -0700 @@ -1,53 +1,53 @@ Network Working Group D. Farinacci Internet-Draft V. Fuller Intended status: Standards Track D. Meyer -Expires: September 6, 2018 D. Lewis +Expires: September 20, 2018 D. Lewis Cisco Systems A. Cabellos (Ed.) UPC/BarcelonaTech - March 5, 2018 + March 19, 2018 The Locator/ID Separation Protocol (LISP) - draft-ietf-lisp-rfc6830bis-11 + draft-ietf-lisp-rfc6830bis-12 Abstract - This document describes the data-plane protocol for the Locator/ID + This document describes the Data-Plane protocol for the Locator/ID Separation Protocol (LISP). LISP defines two namespaces, End-point Identifiers (EIDs) that identify end-hosts and Routing Locators (RLOCs) that identify network attachment points. With this, LISP effectively separates control from data, and allows routers to create overlay networks. LISP-capable routers exchange encapsulated packets - according to EID-to-RLOC mappings stored in a local map-cache. + according to EID-to-RLOC mappings stored in a local Map-Cache. LISP requires no change to either host protocol stacks or to underlay routers and offers Traffic Engineering, multihoming and mobility, among other features. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on September 6, 2018. + This Internet-Draft will expire on September 20, 2018. Copyright Notice Copyright (c) 2018 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents @@ -72,99 +72,98 @@ 7. Dealing with Large Encapsulated Packets . . . . . . . . . . . 19 7.1. A Stateless Solution to MTU Handling . . . . . . . . . . 20 7.2. A Stateful Solution to MTU Handling . . . . . . . . . . . 21 8. Using Virtualization and Segmentation with LISP . . . . . . . 21 9. Routing Locator Selection . . . . . . . . . . . . . . . . . . 22 10. Routing Locator Reachability . . . . . . . . . . . . . . . . 24 10.1. Echo Nonce Algorithm . . . . . . . . . . . . . . . . . . 25 11. EID Reachability within a LISP Site . . . . . . . . . . . . . 26 12. Routing Locator Hashing . . . . . . . . . . . . . . . . . . . 27 13. Changing the Contents of EID-to-RLOC Mappings . . . . . . . . 28 - 13.1. Clock Sweep . . . . . . . . . . . . . . . . . . . . . . 29 - 13.2. Database Map-Versioning . . . . . . . . . . . . . . . . 29 - 14. Multicast Considerations . . . . . . . . . . . . . . . . . . 30 - 15. Router Performance Considerations . . . . . . . . . . . . . . 31 + 13.1. Database Map-Versioning . . . . . . . . . . . . . . . . 29 + 14. Multicast Considerations . . . . . . . . . . . . . . . . . . 29 + 15. Router Performance Considerations . . . . . . . . . . . . . . 30 16. Security Considerations . . . . . . . . . . . . . . . . . . . 31 17. Network Management Considerations . . . . . . . . . . . . . . 32 18. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 32 - 18.1. LISP UDP Port Numbers . . . . . . . . . . . . . . . . . 33 - 19. References . . . . . . . . . . . . . . . . . . . . . . . . . 33 - 19.1. Normative References . . . . . . . . . . . . . . . . . . 33 - 19.2. Informative References . . . . . . . . . . . . . . . . . 34 - - Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 39 - Appendix B. Document Change Log . . . . . . . . . . . . . . . . 39 - B.1. Changes to draft-ietf-lisp-rfc6830bis-11 . . . . . . . . 40 - B.2. Changes to draft-ietf-lisp-rfc6830bis-10 . . . . . . . . 40 - B.3. Changes to draft-ietf-lisp-rfc6830bis-09 . . . . . . . . 40 - B.4. Changes to draft-ietf-lisp-rfc6830bis-08 . . . . . . . . 40 - B.5. Changes to draft-ietf-lisp-rfc6830bis-07 . . . . . . . . 41 - B.6. Changes to draft-ietf-lisp-rfc6830bis-06 . . . . . . . . 41 - B.7. Changes to draft-ietf-lisp-rfc6830bis-05 . . . . . . . . 41 - B.8. Changes to draft-ietf-lisp-rfc6830bis-04 . . . . . . . . 41 - B.9. Changes to draft-ietf-lisp-rfc6830bis-03 . . . . . . . . 42 - B.10. Changes to draft-ietf-lisp-rfc6830bis-02 . . . . . . . . 42 - B.11. Changes to draft-ietf-lisp-rfc6830bis-01 . . . . . . . . 42 - B.12. Changes to draft-ietf-lisp-rfc6830bis-00 . . . . . . . . 42 + 18.1. LISP UDP Port Numbers . . . . . . . . . . . . . . . . . 32 + 19. References . . . . . . . . . . . . . . . . . . . . . . . . . 32 + 19.1. Normative References . . . . . . . . . . . . . . . . . . 32 + 19.2. Informative References . . . . . . . . . . . . . . . . . 33 + Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 38 + Appendix B. Document Change Log . . . . . . . . . . . . . . . . 38 + B.1. Changes to draft-ietf-lisp-rfc6830bis-12 . . . . . . . . 39 + B.2. Changes to draft-ietf-lisp-rfc6830bis-11 . . . . . . . . 39 + B.3. Changes to draft-ietf-lisp-rfc6830bis-10 . . . . . . . . 39 + B.4. Changes to draft-ietf-lisp-rfc6830bis-09 . . . . . . . . 39 + B.5. Changes to draft-ietf-lisp-rfc6830bis-08 . . . . . . . . 40 + B.6. Changes to draft-ietf-lisp-rfc6830bis-07 . . . . . . . . 40 + B.7. Changes to draft-ietf-lisp-rfc6830bis-06 . . . . . . . . 40 + B.8. Changes to draft-ietf-lisp-rfc6830bis-05 . . . . . . . . 41 + B.9. Changes to draft-ietf-lisp-rfc6830bis-04 . . . . . . . . 41 + B.10. Changes to draft-ietf-lisp-rfc6830bis-03 . . . . . . . . 41 + B.11. Changes to draft-ietf-lisp-rfc6830bis-02 . . . . . . . . 41 + B.12. Changes to draft-ietf-lisp-rfc6830bis-01 . . . . . . . . 41 + B.13. Changes to draft-ietf-lisp-rfc6830bis-00 . . . . . . . . 41 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 42 1. Introduction This document describes the Locator/Identifier Separation Protocol (LISP). LISP is an encapsulation protocol built around the fundamental idea of separating the topological location of a network attachment point from the node's identity [CHIAPPA]. As a result LISP creates two namespaces: Endpoint Identifiers (EIDs), that are used to identify end-hosts (e.g., nodes or Virtual Machines) and routable Routing Locators (RLOCs), used to identify network attachment points. LISP then defines functions for mapping between the two namespaces and for encapsulating traffic originated by devices using non-routable EIDs for transport across a network infrastructure that routes and forwards using RLOCs. LISP encapsulation uses a dynamic form of tunneling where no static provisioning is required or necessary. - LISP is an overlay protocol that separates control from data-plane, - this document specifies the data-plane, how LISP-capable routers + LISP is an overlay protocol that separates control from Data-Plane, + this document specifies the Data-Plane, how LISP-capable routers (Tunnel Routers) exchange packets by encapsulating them to the appropriate location. Tunnel routers are equipped with a cache, - called map-cache, that contains EID-to-RLOC mappings. The map-cache + called Map-Cache, that contains EID-to-RLOC mappings. The Map-Cache is populated using the LISP Control-Plane protocol [I-D.ietf-lisp-rfc6833bis]. LISP does not require changes to either host protocol stack or to underlay routers. By separating the EID from the RLOC space, LISP offers native Traffic Engineering, multihoming and mobility, among other features. Creation of LISP was initially motivated by discussions during the IAB-sponsored Routing and Addressing Workshop held in Amsterdam in October 2006 (see [RFC4984]). - This document specifies the LISP data-plane encapsulation and other + This document specifies the LISP Data-Plane encapsulation and other LISP forwarding node functionality while [I-D.ietf-lisp-rfc6833bis] specifies the LISP control plane. LISP deployment guidelines can be found in [RFC7215] and [RFC6835] describes considerations for network operational management. Finally, [I-D.ietf-lisp-introduction] describes the LISP architecture. 2. Requirements Notation The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. 3. Definition of Terms Address Family Identifier (AFI): AFI is a term used to describe an address encoding in a packet. An address family that pertains to - the data-plane. See [AFN] and [RFC3232] for details. An AFI + the Data-Plane. See [AFN] and [RFC3232] for details. An AFI value of 0 used in this specification indicates an unspecified encoded address where the length of the address is 0 octets following the 16-bit AFI value of 0. Anycast Address: Anycast Address is a term used in this document to refer to the same IPv4 or IPv6 address configured and used on multiple systems at the same time. An EID or RLOC can be an anycast address in each of their own address spaces. Client-side: Client-side is a term used in this document to indicate @@ -197,21 +196,21 @@ distributed database that contains all known EID-Prefix-to-RLOC mappings. Each potential ETR typically contains a small piece of the database: the EID-to-RLOC mappings for the EID-Prefixes "behind" the router. These map to one of the router's own globally visible IP addresses. Note that there MAY be transient conditions when the EID-Prefix for the site and Locator-Set for each EID-Prefix may not be the same on all ETRs. This has no negative implications, since a partial set of Locators can be used. - EID-to-RLOC Map-Cache: The EID-to-RLOC map-cache is generally + EID-to-RLOC Map-Cache: The EID-to-RLOC Map-Cache is generally short-lived, on-demand table in an ITR that stores, tracks, and is responsible for timing out and otherwise validating EID-to-RLOC mappings. This cache is distinct from the full "database" of EID- to-RLOC mappings; it is dynamic, local to the ITR(s), and relatively small, while the database is distributed, relatively static, and much more global in scope. EID-Prefix: An EID-Prefix is a power-of-two block of EIDs that are allocated to a site by an address allocation authority. EID- Prefixes are associated with a set of RLOC addresses. EID-Prefix @@ -449,44 +448,44 @@ host. Similarly, the ETR might be the last-hop router directly connected to the destination host. Another example, perhaps for a VPN service outsourced to an ISP by a site, the ITR could be the site's border router at the service provider attachment point. Mixing and matching of site-operated, ISP-operated, and other Tunnel Routers is allowed for maximum flexibility. 4.1. Packet Flow Sequence This section provides an example of the unicast packet flow, - including also control-plane information as specified in + including also Control-Plane information as specified in [I-D.ietf-lisp-rfc6833bis]. The example also assumes the following conditions: o Source host "host1.abc.example.com" is sending a packet to "host2.xyz.example.com", exactly what host1 would do if the site was not using LISP. o Each site is multihomed, so each Tunnel Router has an address (RLOC) assigned from the service provider address block for each provider to which that particular Tunnel Router is attached. o The ITR(s) and ETR(s) are directly connected to the source and destination, respectively, but the source and destination can be located anywhere in the LISP site. o A Map-Request is sent for an external destination when the destination is not found in the forwarding table or matches a default route. Map-Requests are sent to the mapping database - system by using the LISP control-plane protocol documented in + system by using the LISP Control-Plane protocol documented in [I-D.ietf-lisp-rfc6833bis]. o Map-Replies are sent on the underlying routing system topology - using the [I-D.ietf-lisp-rfc6833bis] control-plane protocol. + using the [I-D.ietf-lisp-rfc6833bis] Control-Plane protocol. Client host1.abc.example.com wants to communicate with server host2.xyz.example.com: 1. host1.abc.example.com wants to open a TCP connection to host2.xyz.example.com. It does a DNS lookup on host2.xyz.example.com. An A/AAAA record is returned. This address is the destination EID. The locally assigned address of host1.abc.example.com is used as the source EID. An IPv4 or IPv6 packet is built and forwarded through the LISP site as a normal @@ -508,22 +507,22 @@ 5. The ETR looks at the destination EID of the Map-Request and matches it against the prefixes in the ETR's configured EID-to- RLOC mapping database. This is the list of EID-Prefixes the ETR is supporting for the site it resides in. If there is no match, the Map-Request is dropped. Otherwise, a LISP Map-Reply is returned to the ITR. 6. The ITR receives the Map-Reply message, parses the message (to check for format validity), and stores the mapping information from the packet. This information is stored in the ITR's EID-to- - RLOC map-cache. Note that the map-cache is an on-demand cache. - An ITR will manage its map-cache in such a way that optimizes for + RLOC Map-Cache. Note that the Map-Cache is an on-demand cache. + An ITR will manage its Map-Cache in such a way that optimizes for its resource constraints. 7. Subsequent packets from host1.abc.example.com to host2.xyz.example.com will have a LISP header prepended by the ITR using the appropriate RLOC as the LISP header destination address learned from the ETR. Note that the packet MAY be sent to a different ETR than the one that returned the Map-Reply due to the source site's hashing policy or the destination site's Locator-Set policy. @@ -715,21 +714,21 @@ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ E: The E-bit is the echo-nonce-request bit. This bit MUST be ignored and has no meaning when the N-bit is set to 0. When the N-bit is set to 1 and this bit is set to 1, an ITR is requesting that the nonce value in the 'Nonce' field be echoed back in LISP- encapsulated packets when the ITR is also an ETR. See Section 10.1 for details. V: The V-bit is the Map-Version present bit. When this bit is set to - 1, the N-bit MUST be 0. Refer to Section 13.2 for more details. + 1, the N-bit MUST be 0. Refer to Section 13.1 for more details. This bit indicates that the LISP header is encoded in this case as: 0 x 0 1 x x x x +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |N|L|E|V|I|R|K|K| Source Map-Version | Dest Map-Version | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Instance ID/Locator-Status-Bits | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ @@ -751,25 +750,25 @@ on transmit and MUST be ignored on receipt. KK: The KK-bits are a 2-bit field used when encapsulated packets are encrypted. The field is set to 00 when the packet is not encrypted. See [RFC8061] for further information. LISP Nonce: The LISP 'Nonce' field is a 24-bit value that is randomly generated by an ITR when the N-bit is set to 1. Nonce generation algorithms are an implementation matter but are required to generate different nonces when sending to different - destinations. However, the same nonce can be used for a period of - time when encapsulating to the same ETR. The nonce is also used - when the E-bit is set to request the nonce value to be echoed by - the other side when packets are returned. When the E-bit is clear - but the N-bit is set, a remote ITR is either echoing a previously + RLOCs. However, the same nonce can be used for a period of time + when encapsulating to the same ETR. The nonce is also used when + the E-bit is set to request the nonce value to be echoed by the + other side when packets are returned. When the E-bit is clear but + the N-bit is set, a remote ITR is either echoing a previously requested echo-nonce or providing a random nonce. See Section 10.1 for more details. LISP Locator-Status-Bits (LSBs): When the L-bit is also set, the 'Locator-Status-Bits' field in the LISP header is set by an ITR to indicate to an ETR the up/down status of the Locators in the source site. Each RLOC in a Map-Reply is assigned an ordinal value from 0 to n-1 (when there are n RLOCs in a mapping entry). The Locator-Status-Bits are numbered from 0 to n-1 from the least significant bit of the field. The field is 32 bits when the I-bit @@ -861,34 +860,34 @@ 6. LISP EID-to-RLOC Map-Cache ITRs and PITRs maintain an on-demand cache, referred as LISP EID-to- RLOC Map-Cache, that contains mappings from EID-prefixes to locator sets. The cache is used to encapsulate packets from the EID space to the corresponding RLOC network attachment point. When an ITR/PITR receives a packet from inside of the LISP site to destinations outside of the site a longest-prefix match lookup of the - EID is done to the map-cache. + EID is done to the Map-Cache. - When the lookup succeeds, the Locator-Set retrieved from the map- - cache is used to send the packet to the EID's topological location. + When the lookup succeeds, the Locator-Set retrieved from the Map- + Cache is used to send the packet to the EID's topological location. If the lookup fails, the ITR/PITR needs to retrieve the mapping using - the LISP control-plane protocol [I-D.ietf-lisp-rfc6833bis]. The - mapping is then stored in the local map-cache to forward subsequent + the LISP Control-Plane protocol [I-D.ietf-lisp-rfc6833bis]. The + mapping is then stored in the local Map-Cache to forward subsequent packets addressed to the same EID-prefix. - The map-cache is a local cache of mappings, entries are expired based + The Map-Cache is a local cache of mappings, entries are expired based on the associated Time to live. In addition, entries can be updated with more current information, see Section 13 for further information - on this. Finally, the map-cache also contains reachability + on this. Finally, the Map-Cache also contains reachability information about EIDs and RLOCs, and uses LISP reachability information mechanisms to determine the reachability of RLOCs, see Section 10 for the specific mechanisms. 7. Dealing with Large Encapsulated Packets This section proposes two mechanisms to deal with packets that exceed the path MTU between the ITR and ETR. It is left to the implementor to decide if the stateless or stateful @@ -996,31 +995,31 @@ When an ETR decapsulates a packet, the Instance ID from the LISP header is used as a table identifier to locate the forwarding table to use for the inner destination EID lookup. For example, an 802.1Q VLAN tag or VPN identifier could be used as a 24-bit Instance ID. See [I-D.ietf-lisp-vpn] for LISP VPN use-case details. The Instance ID that is stored in the mapping database when LISP-DDT - [RFC8111] is used is 32 bits in length. That means the control-plane - can store more instances than a given data-plane can use. Multiple - data-planes can use the same 32-bit space as long as the low-order 24 + [RFC8111] is used is 32 bits in length. That means the Control-Plane + can store more instances than a given Data-Plane can use. Multiple + Data-Planes can use the same 32-bit space as long as the low-order 24 bits don't overlap among xTRs. 9. Routing Locator Selection - The map-cache contains the state used by ITRs and PITRs to + The Map-Cache contains the state used by ITRs and PITRs to encapsulate packets. When an ITR/PITR receives a packet from inside the LISP site to a destination outside of the site a longest-prefix - match lookup of the EID is done to the map-cache (see Section 6). + match lookup of the EID is done to the Map-Cache (see Section 6). The lookup returns a single Locator-Set containing a list of RLOCs corresponding to the EID's topological location. Each RLOC in the Locator-Set is associated with a 'Priority' and 'Weight', this information is used to select the RLOC to encapsulate. The RLOC with the lowest 'Priority' is selected. An RLOC with 'Priority' 255 means that MUST NOT be used for forwarding. When multiple RLOC have the same 'Priority' then the 'Weight' states how to load balance traffic among them. The value of the 'Weight' represents the relative weight of the total packets that match the @@ -1086,22 +1085,22 @@ reachable when the R-bit for the Locator record is set to 1. When the R-bit is set to 0, an ITR or PITR MUST NOT encapsulate to the RLOC. Neither the information contained in a Map-Reply nor that stored in the mapping database system provides reachability information for RLOCs. Note that reachability is not part of the mapping system and is determined using one or more of the Routing Locator reachability algorithms described in the next section. 10. Routing Locator Reachability - Several data-plane mechanisms for determining RLOC reachability are - currently defined. Please note that additional control-plane based + Several Data-Plane mechanisms for determining RLOC reachability are + currently defined. Please note that additional Control-Plane based reachability mechanisms are defined in [I-D.ietf-lisp-rfc6833bis]. 1. An ETR MAY examine the Locator-Status-Bits in the LISP header of an encapsulated data packet received from an ITR. If the ETR is also acting as an ITR and has traffic to return to the original ITR site, it can use this status information to help select an RLOC. 2. When an ETR receives an encapsulated packet from an ITR, the source RLOC from the outer header of the packet is likely up. @@ -1156,21 +1155,21 @@ most cases, the ETR can also reach the ITR but cannot assume this to be true, due to the possibility of path asymmetry. In the presence of unidirectional traffic flow from an ITR to an ETR, the ITR SHOULD NOT use the lack of return traffic as an indication that the ETR is unreachable. Instead, it MUST use an alternate mechanism to determine reachability. 10.1. Echo Nonce Algorithm When data flows bidirectionally between Locators from different - sites, a data-plane mechanism called "nonce echoing" can be used to + sites, a Data-Plane mechanism called "nonce echoing" can be used to determine reachability between an ITR and ETR. When an ITR wants to solicit a nonce echo, it sets the N- and E-bits and places a 24-bit nonce [RFC4086] in the LISP header of the next encapsulated data packet. When this packet is received by the ETR, the encapsulated packet is forwarded as normal. When the ETR next sends a data packet to the ITR, it includes the nonce received earlier with the N-bit set and E-bit cleared. The ITR sees this "echoed nonce" and knows that the path to and from the ETR is up. @@ -1227,21 +1226,21 @@ It is recognized that there are no simple solutions to the site partitioning problem because it is hard to know which part of the EID-Prefix range is partitioned and which Locators can reach any sub- ranges of the EID-Prefixes. Note that this is not a new problem introduced by the LISP architecture. The problem exists today when a multihomed site uses BGP to advertise its reachability upstream. 12. Routing Locator Hashing When an ETR provides an EID-to-RLOC mapping in a Map-Reply message - that is stored in the map-cache of a requesting ITR, the Locator-Set + that is stored in the Map-Cache of a requesting ITR, the Locator-Set for the EID-Prefix MAY contain different Priority and Weight values for each locator address. When more than one best Priority Locator exists, the ITR can decide how to load-share traffic against the corresponding Locators. The following hash algorithm MAY be used by an ITR to select a Locator for a packet destined to an EID for the EID-to-RLOC mapping: 1. Either a source and destination address hash or the traditional 5-tuple hash can be used. The traditional 5-tuple hash includes @@ -1281,22 +1280,22 @@ Since the LISP architecture uses a caching scheme to retrieve and store EID-to-RLOC mappings, the only way an ITR can get a more up-to- date mapping is to re-request the mapping. However, the ITRs do not know when the mappings change, and the ETRs do not keep track of which ITRs requested its mappings. For scalability reasons, it is desirable to maintain this approach but need to provide a way for ETRs to change their mappings and inform the sites that are currently communicating with the ETR site using such mappings. - This section defines data-plane mechanisms for updating EID-to-RLOC - mappings. Additionally, the Solicit-Map Request (SMR) control-plane + This section defines a Data-Plane mechanism for updating EID-to-RLOC + mappings. Additionally, the Solicit-Map Request (SMR) Control-Plane updating mechanism is specified in [I-D.ietf-lisp-rfc6833bis]. When adding a new Locator record in lexicographic order to the end of a Locator-Set, it is easy to update mappings. We assume that new mappings will maintain the same Locator ordering as the old mapping but will just have new Locators appended to the end of the list. So, some ITRs can have a new mapping while other ITRs have only an old mapping that is used until they time out. When an ITR has only an old mapping but detects bits set in the Locator-Status-Bits that correspond to Locators beyond the list it has cached, it simply @@ -1317,55 +1316,27 @@ well as setting the corresponding Locator-Status-Bit to 0. This forces ITRs with old or new mappings to avoid using the removed Locator. If many changes occur to a mapping over a long period of time, one will find empty record slots in the middle of the Locator-Set and new records appended to the Locator-Set. At some point, it would be useful to compact the Locator-Set so the Locator-Status-Bit settings can be efficiently packed. - We propose here two approaches for Locator-Set compaction: one - operational mechanism (clock sweep) and one protocol mechanisms (Map- - Versioning). Please note that in addition the Solicit-Map Request - (specified in [I-D.ietf-lisp-rfc6833bis]) is a control-plane - mechanisms that can be used to update EID-to-RLOC mappings. - -13.1. Clock Sweep - - The clock sweep approach uses planning in advance and the use of - count-down TTLs to time out mappings that have already been cached. - The default setting for an EID-to-RLOC mapping TTL is 24 hours. So, - there is a 24-hour window to time out old mappings. The following - clock sweep procedure is used: - - 1. 24 hours before a mapping change is to take effect, a network - administrator configures the ETRs at a site to start the clock - sweep window. - - 2. During the clock sweep window, ETRs continue to send Map-Reply - messages with the current (unchanged) mapping records. The TTL - for these mappings is set to 1 hour. - - 3. 24 hours later, all previous cache entries will have timed out, - and any active cache entries will time out within 1 hour. During - this 1-hour window, the ETRs continue to send Map-Reply messages - with the current (unchanged) mapping records with the TTL set to - 1 minute. - - 4. At the end of the 1-hour window, the ETRs will send Map-Reply - messages with the new (changed) mapping records. So, any active - caches can get the new mapping contents right away if not cached, - or in 1 minute if they had the mapping cached. The new mappings - are cached with a TTL equal to the TTL in the Map-Reply. + We propose here a Data-Plane mechanism (Map-Versioning) to update the + contents of EID-to-RLOC mappings. Please note that in addition the + Solicit-Map Request (specified in [I-D.ietf-lisp-rfc6833bis]) is a + Control-Plane mechanisms that can be used to update EID-to-RLOC + mappings. -13.2. Database Map-Versioning +13.1. Database Map-Versioning When there is unidirectional packet flow between an ITR and ETR, and the EID-to-RLOC mappings change on the ETR, it needs to inform the ITR so encapsulation to a removed Locator can stop and can instead be started to a new Locator in the Locator-Set. An ETR, when it sends Map-Reply messages, conveys its own Map-Version Number. This is known as the Destination Map-Version Number. ITRs include the Destination Map-Version Number in packets they encapsulate to the site. When an ETR decapsulates a packet and @@ -1434,136 +1405,127 @@ few implementation techniques can be used to incrementally implement LISP: o When a tunnel-encapsulated packet is received by an ETR, the outer destination address may not be the address of the router. This makes it challenging for the control plane to get packets from the hardware. This may be mitigated by creating special Forwarding Information Base (FIB) entries for the EID-Prefixes of EIDs served by the ETR (those for which the router provides an RLOC translation). These FIB entries are marked with a flag indicating - that control-plane processing SHOULD be performed. The forwarding + that Control-Plane processing SHOULD be performed. The forwarding logic of testing for particular IP protocol number values is not necessary. There are a few proven cases where no changes to - existing deployed hardware were needed to support the LISP data- - plane. + existing deployed hardware were needed to support the LISP Data- + Plane. o On an ITR, prepending a new IP header consists of adding more octets to a MAC rewrite string and prepending the string as part of the outgoing encapsulation procedure. Routers that support Generic Routing Encapsulation (GRE) tunneling [RFC2784] or 6to4 tunneling [RFC3056] may already support this action. o A packet's source address or interface the packet was received on can be used to select VRF (Virtual Routing/Forwarding). The VRF's routing table can be used to find EID-to-RLOC mappings. - For performance issues related to map-cache management, see + For performance issues related to Map-Cache management, see Section 16. 16. Security Considerations Security considerations for LISP are discussed in [RFC7833]. A complete LISP threat analysis can be found in [RFC7835], in what follows we provide a summary. The optional mechanisms of gleaning is offered to directly obtain a mapping from the LISP encapsulated packets. Specifically, an xTR can learn the EID-to-RLOC mapping by inspecting the source RLOC and source EID of an encapsulated packet, and insert this new mapping - into its map-cache. An off-path attacker can spoof the source EID + into its Map-Cache. An off-path attacker can spoof the source EID address to divert the traffic sent to the victim's spoofed EID. If the attacker spoofs the source RLOC, it can mount a DoS attack by redirecting traffic to the spoofed victim's RLOC, potentially overloading it. - The LISP Data-Plane defines several mechanisms to monitor RLOC data- - plane reachability, in this context Locator-Status Bits, Nonce- + The LISP Data-Plane defines several mechanisms to monitor RLOC Data- + Plane reachability, in this context Locator-Status Bits, Nonce- Present and Echo-Nonce bits of the LISP encapsulation header can be manipulated by an attacker to mount a DoS attack. An off-path attacker able to spoof the RLOC of a victim's xTR can manipulate such mechanisms to declare a set of RLOCs unreachable. This can be used also, for instance, to declare only one RLOC reachable with the aim of overload it. - Map-Versioning is a data-plane mechanism used to signal a peering xTR + Map-Versioning is a Data-Plane mechanism used to signal a peering xTR that a local EID-to-RLOC mapping has been updated, so that the peering xTR uses LISP Control-Plane signaling message to retrieve a fresh mapping. This can be used by an attacker to forge the map- versioning field of a LISP encapsulated header and force an excessive amount of signaling between xTRs that may overload them. Most of the attack vectors can be mitigated with careful deployment and configuration, information learned opportunistically (such as LSB or gleaning) SHOULD be verified with other reachability mechanisms. In addition, systematic rate-limitation and filtering is an effective - technique to mitigate attacks that aim to overload the control-plane. + technique to mitigate attacks that aim to overload the Control-Plane. 17. Network Management Considerations Considerations for network management tools exist so the LISP protocol suite can be operationally managed. These mechanisms can be found in [RFC7052] and [RFC6835]. 18. IANA Considerations This section provides guidance to the Internet Assigned Numbers Authority (IANA) regarding registration of values related to this - data-plane LISP specification, in accordance with BCP 26 [RFC8126]. + Data-Plane LISP specification, in accordance with BCP 26 [RFC8126]. 18.1. LISP UDP Port Numbers The IANA registry has allocated UDP port number 4341 for the LISP - data-plane. IANA has updated the description for UDP port 4341 as + Data-Plane. IANA has updated the description for UDP port 4341 as follows: lisp-data 4341 udp LISP Data Packets 19. References 19.1. Normative References [I-D.ietf-lisp-rfc6833bis] Fuller, V., Farinacci, D., and A. Cabellos-Aparicio, "Locator/ID Separation Protocol (LISP) Control-Plane", - draft-ietf-lisp-rfc6833bis-07 (work in progress), December - 2017. + draft-ietf-lisp-rfc6833bis-09 (work in progress), March + 2018. [RFC0768] Postel, J., "User Datagram Protocol", STD 6, RFC 768, DOI 10.17487/RFC0768, August 1980, . [RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791, DOI 10.17487/RFC0791, September 1981, . [RFC2474] Nichols, K., Blake, S., Baker, F., and D. Black, "Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers", RFC 2474, DOI 10.17487/RFC2474, December 1998, . [RFC3168] Ramakrishnan, K., Floyd, S., and D. Black, "The Addition of Explicit Congestion Notification (ECN) to IP", RFC 3168, DOI 10.17487/RFC3168, September 2001, . - [RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker, - "Randomness Requirements for Security", BCP 106, RFC 4086, - DOI 10.17487/RFC4086, June 2005, - . - - [RFC6275] Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility - Support in IPv6", RFC 6275, DOI 10.17487/RFC6275, July - 2011, . - [RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6 (IPv6) Specification", STD 86, RFC 8200, DOI 10.17487/RFC8200, July 2017, . 19.2. Informative References [AFN] IANA, "Address Family Numbers", August 2016, . @@ -1593,22 +1555,22 @@ RLOCs", draft-ietf-lisp-predictive-rlocs-01 (work in progress), November 2017. [I-D.ietf-lisp-sec] Maino, F., Ermagan, V., Cabellos-Aparicio, A., and D. Saucez, "LISP-Security (LISP-SEC)", draft-ietf-lisp-sec-14 (work in progress), October 2017. [I-D.ietf-lisp-signal-free-multicast] Moreno, V. and D. Farinacci, "Signal-Free LISP Multicast", - draft-ietf-lisp-signal-free-multicast-08 (work in - progress), February 2018. + draft-ietf-lisp-signal-free-multicast-09 (work in + progress), March 2018. [I-D.ietf-lisp-vpn] Moreno, V. and D. Farinacci, "LISP Virtual Private Networks (VPNs)", draft-ietf-lisp-vpn-01 (work in progress), November 2017. [LISA96] Lear, E., Tharp, D., Katinsky, J., and J. Coffin, "Renumbering: Threat or Menace?", Usenix Tenth System Administration Conference (LISA 96), October 1996. @@ -1642,20 +1604,25 @@ [RFC3232] Reynolds, J., Ed., "Assigned Numbers: RFC 1700 is Replaced by an On-line Database", RFC 3232, DOI 10.17487/RFC3232, January 2002, . [RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP: Session Initiation Protocol", RFC 3261, DOI 10.17487/RFC3261, June 2002, . + [RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker, + "Randomness Requirements for Security", BCP 106, RFC 4086, + DOI 10.17487/RFC4086, June 2005, + . + [RFC4192] Baker, F., Lear, E., and R. Droms, "Procedures for Renumbering an IPv6 Network without a Flag Day", RFC 4192, DOI 10.17487/RFC4192, September 2005, . [RFC4632] Fuller, V. and T. Li, "Classless Inter-domain Routing (CIDR): The Internet Address Assignment and Aggregation Plan", BCP 122, RFC 4632, DOI 10.17487/RFC4632, August 2006, . @@ -1666,20 +1633,24 @@ [RFC4984] Meyer, D., Ed., Zhang, L., Ed., and K. Fall, Ed., "Report from the IAB Workshop on Routing and Addressing", RFC 4984, DOI 10.17487/RFC4984, September 2007, . [RFC5944] Perkins, C., Ed., "IP Mobility Support for IPv4, Revised", RFC 5944, DOI 10.17487/RFC5944, November 2010, . + [RFC6275] Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility + Support in IPv6", RFC 6275, DOI 10.17487/RFC6275, July + 2011, . + [RFC6831] Farinacci, D., Meyer, D., Zwiebel, J., and S. Venaas, "The Locator/ID Separation Protocol (LISP) for Multicast Environments", RFC 6831, DOI 10.17487/RFC6831, January 2013, . [RFC6832] Lewis, D., Meyer, D., Farinacci, D., and V. Fuller, "Interworking between Locator/ID Separation Protocol (LISP) and Non-LISP Sites", RFC 6832, DOI 10.17487/RFC6832, January 2013, . @@ -1784,80 +1755,91 @@ The LISP working group would like to give a special thanks to Jari Arkko, the Internet Area AD at the time that the set of LISP documents were being prepared for IESG last call, and for his meticulous reviews and detailed commentaries on the 7 working group last call documents progressing toward standards-track RFCs. Appendix B. Document Change Log [RFC Editor: Please delete this section on publication as RFC.] -B.1. Changes to draft-ietf-lisp-rfc6830bis-11 +B.1. Changes to draft-ietf-lisp-rfc6830bis-12 + + o Posted March IETF Week 2018. + + o Clarified that a new nonce is required per RLOC. + + o Removed 'Clock Sweep' section. This text must be placed in a new + OAM document. + + o Some references changed from normative to informative + +B.2. Changes to draft-ietf-lisp-rfc6830bis-11 o Posted March 2018. o Removed sections 16, 17 and 18 (Mobility, Deployment and Traceroute considerations). This text must be placed in a new OAM document. -B.2. Changes to draft-ietf-lisp-rfc6830bis-10 +B.3. Changes to draft-ietf-lisp-rfc6830bis-10 o Posted March 2018. - o Updated section 'Router Locator Selection' stating that the data- - plane MUST follow what's stored in the map-cache (priorities and + o Updated section 'Router Locator Selection' stating that the Data- + Plane MUST follow what's stored in the Map-Cache (priorities and weights). o Section 'Routing Locator Reachability': Removed bullet point 2 (ICMP Network/Host Unreachable),3 (hints from BGP),4 (ICMP Port Unreachable),5 (receive a Map-Reply as a response) and RLOC probing o Removed 'Solicit-Map Request'. -B.3. Changes to draft-ietf-lisp-rfc6830bis-09 +B.4. Changes to draft-ietf-lisp-rfc6830bis-09 o Posted January 2018. o Add more details in section 5.3 about DSCP processing during encapsulation and decapsulation. o Added clarity to definitions in the Definition of Terms section from various commenters. o Removed PA and PI definitions from Definition of Terms section. o More editorial changes. o Removed 4342 from IANA section and move to RFC6833 IANA section. -B.4. Changes to draft-ietf-lisp-rfc6830bis-08 +B.5. Changes to draft-ietf-lisp-rfc6830bis-08 o Posted January 2018. o Remove references to research work for any protocol mechanisms. o Document scanned to make sure it is RFC 2119 compliant. o Made changes to reflect comments from document WG shepherd Luigi Iannone. o Ran IDNITs on the document. -B.5. Changes to draft-ietf-lisp-rfc6830bis-07 +B.6. Changes to draft-ietf-lisp-rfc6830bis-07 o Posted November 2017. o Rephrase how Instance-IDs are used and don't refer to [RFC1918] addresses. -B.6. Changes to draft-ietf-lisp-rfc6830bis-06 +B.7. Changes to draft-ietf-lisp-rfc6830bis-06 o Posted October 2017. o Put RTR definition before it is used. o Rename references that are now working group drafts. o Remove "EIDs MUST NOT be used as used by a host to refer to other hosts. Note that EID blocks MAY LISP RLOCs". @@ -1866,61 +1848,61 @@ o ETRs may, rather than will, be the ones to send Map-Replies. o Recommend, rather than mandate, max encapsulation headers to 2. o Reference VPN draft when introducing Instance-ID. o Indicate that SMRs can be sent when ITR/ETR are in the same node. o Clarify when private addreses can be used. -B.7. Changes to draft-ietf-lisp-rfc6830bis-05 +B.8. Changes to draft-ietf-lisp-rfc6830bis-05 o Posted August 2017. o Make it clear that a Reencapsulating Tunnel Router is an RTR. -B.8. Changes to draft-ietf-lisp-rfc6830bis-04 +B.9. Changes to draft-ietf-lisp-rfc6830bis-04 o Posted July 2017. o Changed reference of IPv6 RFC2460 to RFC8200. o Indicate that the applicability statement for UDP zero checksums over IPv6 adheres to RFC6936. -B.9. Changes to draft-ietf-lisp-rfc6830bis-03 +B.10. Changes to draft-ietf-lisp-rfc6830bis-03 o Posted May 2017. o Move the control-plane related codepoints in the IANA Considerations section to RFC6833bis. -B.10. Changes to draft-ietf-lisp-rfc6830bis-02 +B.11. Changes to draft-ietf-lisp-rfc6830bis-02 o Posted April 2017. o Reflect some editorial comments from Damien Sausez. -B.11. Changes to draft-ietf-lisp-rfc6830bis-01 +B.12. Changes to draft-ietf-lisp-rfc6830bis-01 o Posted March 2017. o Include references to new RFCs published. o Change references from RFC6833 to RFC6833bis. o Clarified LCAF text in the IANA section. o Remove references to "experimental". -B.12. Changes to draft-ietf-lisp-rfc6830bis-00 +B.13. Changes to draft-ietf-lisp-rfc6830bis-00 o Posted December 2016. o Created working group document from draft-farinacci-lisp -rfc6830-00 individual submission. No other changes made. Authors' Addresses Dino Farinacci Cisco Systems