Network Working Group                                           L. Yong
Internet Draft                                                L. Dunbar
Category: Informational                                          Huawei
                                                                 M. Toy

                                                               A. Isaac
                                                       Juniper Networks
                                                              V. Manral
                                                         Ionos Networks

Expires: March April 2017                                 September 22,                                 October 3, 2016

         Use Cases for Data Center Network Virtualization Overlays




   This document describes Data Center (DC) Network Virtualization data center network virtualization over
   Layer 3
   layer (NVO3) use cases that can be deployed in various data centers
   and serve different applications.

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Table of Contents

   1. Introduction...................................................3
      1.1. Terminology...............................................4
   2. Basic Virtual Networks in a Data Center........................5 NVO3 Networks............................................5
   3. DC Virtual NVO3 Network and External Network Interconnection........6 Interconnection...........6
      3.1. DC Virtual NVO3 Network Access via the Internet................6 Internet...................6
      3.2. DC VN NVO3 Network and SP WAN VPN Interconnection......................8 Interconnection............8
   4. DC Applications Using NVO3.....................................9 NVO3.....................................8
      4.1. Supporting Multiple Technologies..........................9
      4.2. DC Application with Multiple Virtual Networks.............9
      4.3. Virtual Data Center (vDC)................................10
   5. Summary.......................................................11 Summary.......................................................12
   6. Security Considerations.......................................12
   7. IANA Considerations...........................................12
   8. References....................................................12 References....................................................13
      8.1. Normative References.....................................12 References.....................................13
      8.2. Informative References...................................12
   Contributors.....................................................13 References...................................13
   Authors' Addresses...............................................14

1. Introduction

   Server Virtualization virtualization has changed the Information Technology (IT)
   industry in terms of the efficiency, cost, and speed of providing
   new applications and/or services such as cloud applications. However
   traditional Data Center data center (DC) networks have some limits in supporting
   cloud applications and multi tenant networks [RFC7364]. The goal of
   Network Virtualization Overlays in the DC
   data center network virtualization overlay (NVO3) network is to
   decouple the communication among tenant systems from DC physical
   infrastructure networks and to allow one physical network
   infrastructure to provide:

   o  Multi-tenant virtual networks and traffic isolation among the
      virtual networks over the same physical network.

   o  Independent address spaces in individual virtual networks such as
      MAC, IP, TCP/UDP etc.

   o  Flexible Virtual Machines (VM) and/or workload placement
      including the ability to move them from one server to another
      without requiring VM address and configuration changes, and the
      ability to perform a "hot move" with no disruption to the live
      application running on VMs.

   These characteristics of NVO3 help address the issues that cloud
   applications face in Data Centers [RFC7364].

   An NVO3 network may interconnect with another NVO3 virtual network on the
   same physical network, or another physical network (i.e., not the
   physical network that the NVO3 network is over), via a gateway. The
   use case examples for the latter are: 1) DCs that migrate toward an
   NVO3 solution will be done in steps, where a portion of tenant
   systems in a VN is on virtualized servers while others exist on a
   LAN. 2) many DC applications serve to Internet users who are on
   physical networks; 3) some applications are CPU bound, such as Big
   Data analytics, and may not run on virtualized resources. Some
   inter-VN policies can be enforced at the gateway.

   This document describes general NVO3 use cases that apply to various
   data centers. The use cases described here represent DC provider's
   interests and vision for their cloud services. The document groups
   the use cases into three categories from simple to advance in term
   of implementation. However the implementations of these use cases
   are outside the scope of this document. These three categories are
   highlighted below:

   o  Basic NVO3 virtual networks in a DC (Section 2). All Tenant Systems (TS) in the virtual
      network are located within the same DC. The individual virtual networks
      can be either Layer 2 (L2) or Layer 3 (L3). The number of NVO3 virtual
      networks in a DC is much higher than what traditional VLAN based
      virtual networks [IEEE 802.1Q] can support. This case is often
      referred as to the DC East-West traffic.

   o  Virtual networks  A virtual network that span spans across multiple Data Centers and/or
      to customer premises, i.e., an NVO3 virtual network premises where some
      tenant systems in a DC attach to NVO3 networks are constructed and
      interconnect another virtual or physical network outside the data
      center. An enterprise customer may use a traditional carrier VPN
      or an IPsec tunnel over the Internet to communicate with its
      systems in the DC. This is described in Section 3.

   o  DC applications or services require an advanced network that
      contains several NVO3 virtual networks that are interconnected by the
      gateways. Three scenarios are described in Section 4: 1)
      supporting multiple technologies; 2) constructing several virtual
      networks as a tenant network; 3) applying NVO3 to a virtual Data
      Center (vDC).

   The document uses the architecture reference model defined in
   [RFC7365] to describe the use cases.

1.1.  Terminology

   This document uses the terminologies defined in [RFC7365] and
   [RFC4364]. Some additional terms used in the document are listed

   DMZ: Demilitarized Zone. A computer or small sub-network that sits
   between a trusted internal network, such as a corporate private LAN,
   and an un-trusted external network, such as the public Internet.

   DNS: Domain Name Service [RFC1035]

   DC Operator: A role who is responsible to construct and manage cloud
   service instances in their life-cycle and manage DC infrastructure
   that runs these cloud instances.

   DC Provider: A company that uses its DC infrastructure to offer
   cloud services to its customers.

   NAT: Network Address Translation [RFC3022]

   vGW: virtual Gateway; a gateway component used for an NVO3 virtual
   network to interconnect with another virtual/physical network.

   Note that a virtual network in this document refers to an NVO3
   virtual network in a DC [RFC7365].

2. Basic Virtual NVO3 Networks in a Data Center

   A virtual

   An NVO3 network in a DC enables provides communications among Tenant Systems (TS). (TS) in
   a DC. A TS can be a physical server/device or a virtual machine (VM)
   on a server, i.e., end-device [RFC7365]. A DC provider often uses
   NVO3 networks for its internal applications in which each
   application runs on many VMs or physical services and requires
   application segregation.

   A Network Virtual Edge (NVE) can be co-located with a TS, i.e., on is an NVO3 architecture component
   [RFC7365]]. It is responsible to forward and encapsulate the same
   end-device, or reside on a different device, e.g., a top of rack
   switch (ToR). NVO3
   traffic in outbound direction; and decapsulate and forward the NVO3
   traffic in inbound direction [NVO3ARCH]. A virtual network has Network Virtualization
   Authority (NVA) is another NVO3 architecture component [RFC7365]. An
   NVE obtains the reachability information of tenant systems in a virtual NVO3
   network identifier
   (can be globally unique or locally significant at NVEs).

   Tenant Systems from the NVA. The tenant systems attached to the same NVE
   may belong to the a same or different virtual NVO3 networks. An NVE provides tenant traffic
   forwarding/encapsulation and obtains tenant systems reachability
   information from a Network Virtualization Authority (NVA)[NVO3ARCH].
   DC operators can construct multiple separate virtual networks, and
   provide each with own address space.

   Network Virtualization Overlay

   The network virtualization overlay in this context means that a
   virtual network is implemented with an overlay technology, i.e.,
   within a DC
   that has IP infrastructure, tenant DC, NVO3 traffic is encapsulated at its
   local an NVE and carried by a
   tunnel to another NVE where the packet is decapsulated and sent to a
   target tenant system. system [NVO3ARCH]. This architecture decouples tenant system address space and configuration a NVO3
   network construction from the
   infrastructure's, DC physical network configuration,
   which provides great the flexibility for VM placement and mobility. It
   also means that the transit nodes in the infrastructure are network (except
   tunnel end point nodes) carry encapsulated NVO3 traffic but not
   aware of the existence of the virtual
   networks and tenant systems attached to the virtual NVO3 networks. The
   tunneled packets are carried as regular IP packets and are sent to
   NVEs. One In the architecture
   [NVO3ARCH], one tunnel may can carry the NVO3 traffic belonging to multiple virtual different
   NVO3 networks; a virtual network identifier is used for traffic
   demultiplexing. A tunnel in an NVO3
   encapsulation protocol is necessary for NVE to encapsulate the packets from Tenant Systems and encode other
   information on the tunneled packets to support differentiate NVO3 implementation.

   A virtual network implemented by traffic.

   An NVO3 network may be an L2 or L3 domain. The
   virtual network can provides
   switching (L2) or routing (L3) capability to support host (i.e.
   tenent systems) communications. An NVO3 network may required to
   carry unicast traffic and/or multicast, broadcast/unknown (for L2
   only) traffic from/to tenant systems. There are several ways to
   transport virtual NVO3 network BUM traffic [NVO3MCAST].

   It is worth mentioning two distinct cases regarding to NVE location.
   The first is where TSs and an NVE are co-located on a single end
   host/device, which means that the NVE can be aware of the TS's state
   at any time via an internal API. The second is where TSs and an NVE
   are not co-located, with the NVE residing on a network device; in
   this case, a protocol is necessary to allow the NVE to be aware of
   the TS's state [NVO3HYVR2NVE].

  One virtual NVO3 network can provide connectivity to many TSs that attach to
  many different NVEs in a DC. TS dynamic placement and mobility
  results in frequent changes of the binding between a TS and an NVE.
  The TS reachability update mechanisms need be fast enough so that
  the updates do not cause any communication disruption/interruption.
  The capability of supporting many TSs in a virtual network and many
  more virtual networks in a DC is critical for the NVO3 solution.

   If a virtual network spans across multiple DC sites, one design
   using NVO3 is to allow the network to seamlessly span across the
   sites without DC gateway routers' termination. In this case, the
   tunnel between a pair of NVEs can be carried within other
   intermediate tunnels over the Internet or other WANs, or the an intra DC
   tunnel and inter DC tunnels tunnel(s) can be stitched together to form a an
   end-to-end tunnel between the pair of NVEs that are in different DC
   sites. Both cases will form one virtual network across multiple DC

3. DC Virtual NVO3 Network and External Network Interconnection

   Many customers (an enterprise or individuals) who utilize a DC
   provider's compute and storage resources to run their applications
   need to access their systems hosted in a DC through Internet or
   Service Providers' Wide Area Networks (WAN). A DC provider can
   construct a virtual NVO3 network that provides connectivity to all the
   resources designated for a customer and allows the customer to
   access the resources via a virtual gateway (vGW). This, in turn,
   becomes the case of interconnecting a DC virtual an NVO3 network and the virtual
   private network at customer site(s) via (VPN) on the Internet or WANs. wide-area networks (WAN).
   Note that a VPN is not implemented by NVO3 solution. Two use cases
   are described here.

3.1. DC Virtual NVO3 Network Access via the Internet

   A customer can connect to a DC virtual an NVO3 network via the Internet in a
   secure way. Figure 1 illustrates an example of this case. The DC virtual NVO3
   network has an instance at NVE1 and NVE2 and the two NVEs are
   connected via an IP tunnel in the Data Center. A set of tenant
   systems are attached to NVE1 on a server. NVE2 resides on a DC
   Gateway device. NVE2 terminates the tunnel and uses the VNID on the
   packet to pass the packet to the corresponding vGW entity on the DC
   GW (the vGW is the default gateway for the virtual network). A
   customer can access their systems, i.e., TS1 or TSn, in the DC via
   the Internet by using an IPsec tunnel [RFC4301]. The IPsec tunnel is
   configured between the vGW and the customer gateway at the customer
   site. Either a static route or iBGP may be used for prefix
   advertisement. The vGW provides IPsec functionality such as
   authentication scheme and encryption; iBGP protocol traffic is
   carried within the IPsec tunnel. Some vGW features are listed below:

   o  The vGW maintains the TS/NVE mappings and advertises the TS
      prefix to the customer via static route or iBGP.

   o  Some vGW functions such as firewall and load balancer can be
      performed by locally attached network appliance devices.

   o  If the virtual NVO3 network in the DC uses different address space than external
      users, then the vGW needs to provide the NAT function.

   o  More than one IPsec tunnel can be configured for redundancy.

   o  The vGW can be implemented on a server or VM. In this case, IP
      tunnels or IPsec tunnels can be used over the DC infrastructure.

   o  DC operators need to construct a vGW for each customer.

         |   TS1 TSn     |
         |    |...|      |
         |  +-+---+-+    |             Customer Site
         |  |  NVE1 |    |               +-----+
         |  +---+---+    |               | CGW |
         +------+--------+               +--+--+
                |                           *
            L3 Tunnel                       *
                |                           *
   DC GW +------+---------+            .--.  .--.
         |  +---+---+     |           (    '*   '.--.
         |  |  NVE2 |     |        .-.'   *          )
         |  +---+---+     |       (    *  Internet    )
         |  +---+---+.    |        ( *               /
         |  |  vGW  | * * * * * * * * '-'          '-'
         |  +-------+ |   | IPsec       \../ \.--/'
         |   +--------+   | Tunnel

           DC Provider Site

          Figure 1 - DC Virtual Network Access via the Internet

3.2. DC VN NVO3 Network and SP WAN VPN Interconnection

   In this case, an Enterprise customer wants to use a Service Provider
   (SP) WAN VPN [RFC4364] [RFC7432] to interconnect its sites with a
   virtual an
   NVO3 network in a DC site. The Service Provider constructs a VPN for
   the enterprise customer. Each enterprise site peers with an SP PE.
   The DC Provider and VPN Service Provider can build a DC virtual an NVO3 network (VN)
   and a WAN VPN independently, and then interconnect them via a local
   link, or a tunnel between the DC GW and WAN PE devices. The control
   plane interconnection options between the DC and WAN are described
   in RFC4364 [RFC4364]. Using Option A with VRF-LITE [VRF-
   LITE], [VRF-LITE], both
   ASBRs, i.e., DC GW and SP PE, maintain a routing/forwarding table
   (VRF). Using Option B, the DC ASBR and SP ASBR do not maintain the
   VRF table; they only maintain the VN NVO3 network and VPN identifier
   mappings, i.e., label mapping, and swap the label on the packets in
   the forwarding process. Both option A and B allow VN the NVO3 network
   and VPN using own identifier and two identifiers are mapped at DC GW.
   With option C, the VN and VPN use the same identifier and both ASBRs
   perform the tunnel stitching, i.e., tunnel segment mapping. Each
   option has pros/cons [RFC4364] and has been deployed in SP networks
   depending on the applications in use. BGP is used with these options
   for route distribution between DCs and SP WANs. Note that if the DC
   is the SP's Data Center, the DC GW and SP PE in this case can be
   merged into one device that performs the interworking of the VN and
   VPN within an AS.

   The configurations above allow the enterprise networks to
   communicate with the tenant systems attached to the VN NVO3 network in a
   the DC without interfering with the DC provider's underlying
   physical networks and other virtual networks. NVO3 networks in the DC. The enterprise
   can use its own address space in the VN. NVO3 network. The DC provider
   can manage which VM and storage elements attach to the VN. NVO3 network.
   The enterprise customer manages which applications run on the VMs in the VN
   without knowing the location of the VMs in the DC. (See Section 4
   for more)

   Furthermore, in this use case, the DC operator can move the VMs
   assigned to the enterprise from one sever to another in the DC
   without the enterprise customer being aware, i.e., with no impact on
   the enterprise's 'live' applications. Such advanced technologies
   bring DC providers great benefits in offering cloud services, but
   add some requirements for NVO3 [RFC7364] as well.

4. DC Applications Using NVO3

   NVO3 technology provides DC operators with the flexibility in
   designing and deploying different applications in an end-to-end
   virtualization overlay environment. The operators no longer need to
   worry about the constraints of the DC physical network configuration
   when creating VMs and configuring a virtual network. network to connect them. A DC
   provider may use NVO3 in various ways, in conjunction with other
   physical networks and/or virtual networks in the DC for a reason.
   This section highlights some use cases for this goal.

4.1. Supporting Multiple Technologies

   Servers deployed in a large data center are often installed at
   different times, and may have different capabilities/features. Some
   servers may be virtualized, while others may not; some may be
   equipped with virtual switches, while others may not. For the
   servers equipped with Hypervisor-based virtual switches, some may
   support VxLAN [RFC7348] encapsulation, some may support NVGRE
   encapsulation [RFC7637], and some may not support any encapsulation.
   To construct a tenant network among these servers and the ToR
   switches, operators can construct one traditional VLAN network and
   two virtual networks where one uses VxLAN encapsulation and the
   other uses NVGRE, and interconnect these three networks via a
   gateway or virtual GW. The GW performs packet
   encapsulation/decapsulation translation between the networks.

   Another case is that some software of a tenant is high CPU and
   memory consumption, which only makes a sense to run on metal servers;
   other software of the tenant may be good to run on VMs. However
   provider DC infrastructure is configured to use NVO3 to connect to
   VMs and VLAN [IEEE802.1Q] connect to metal services. The tenant
   network requires interworking between NVO3 and traditional VLAN.

4.2. DC Application with Multiple Virtual Networks

   A DC application may necessarily be constructed with multi-tier
   zones, where each zone has different access permissions and runs
   different applications. For example, a three-tier zone design has a
   front zone (Web tier) with Web applications, a mid zone (application
   tier) where service applications such as credit payment or ticket
   booking run, and a back zone (database tier) with Data. External
   users are only able to communicate with the Web application in the
   front zone; the back zone can only receive traffic from the
   application zone. In this case, communications between the zones
   must pass through a GW/firewall. Each zone can be implemented by one
   NVO3 network and a GW/firewall can be used to between two virtual NVO3
   networks, i.e., two zones. A As a result, a tunnel carrying virtual NVO3
   network traffic
   has to must be terminated at the GW/firewall where overlay the NVO3
   traffic is processed.

4.3. Virtual Data Center (vDC)

   An Enterprise Data Center enterprise data center today may deploy routers, switches, and
   network appliance devices to construct its internal network, DMZ,
   and external network access; it may have many servers and storage
   running various applications. With NVO3 technology, a DC Provider
   can construct a virtual Data Center (vDC) over its physical DC
   infrastructure and offer a virtual Data Center service to enterprise
   customers. A vDC at the DC Provider site provides the same
   capability as the physical DC at a customer site. A customer manages
   its own applications running in its vDC. A DC Provider can further
   offer different network service functions to the customer. The
   network service functions may include firewall, DNS, load balancer,
   gateway, etc.

   Figure 2 below illustrates one such scenario at service abstraction
   level. In this example, the vDC contains several L2 VNs (L2VNx,
   L2VNy, L2VNz) to group the tenant systems together on a per-
   application basis, and one L3 VN (L3VNa) for the internal routing. A
   network firewall and gateway runs on a VM or server that connects to
   L3VNa and is used for inbound and outbound traffic processing. A
   load balancer (LB) is used in L2VNx. A VPN is also built between the
   gateway and enterprise router. An Enterprise customer runs
   Web/Mail/Voice applications on VMs within the vDC. The users at the
   Enterprise site access the applications running in the vDC via the
   VPN; Internet users access these applications via the
   gateway/firewall at the provider DC site.


                           Internet                    ^ Internet
                              ^                     +--+---+
                              |                     |  GW  |
                              |                     +--+---+
                              |                        |
                      +-------+--------+            +--+---+
                      |Firewall/Gateway+--- VPN-----+router|
                      +-------+--------+            +-+--+-+
                              |                       |  |
                           ...+....                   |..|
                  +-------: L3 VNa :---------+        LANs
                +-+-+      ........          |
                |LB |          |             |     Enterprise Site
                +-+-+          |             |
               ...+...      ...+...       ...+...
              : L2VNx :    : L2VNy :     : L2VNz :
               .......      .......       .......
                 |..|         |..|          |..|
                 |  |         |  |          |  |
               Web App.     Mail App.      VoIP App.

                        Provider DC Site

             Figure 2 - Virtual Data Center Abstraction View

   The enterprise customer decides which applications should be
   accessible only via the intranet and which should be assessable via
   both the intranet and Internet, and configures the proper security
   policy and gateway function at the firewall/gateway. Furthermore, an
   enterprise customer may want multi-zones in a vDC (See section 4.2)
   for the security and/or the ability to set different QoS levels for
   the different applications.

   The vDC use case requires an NVO3 solution to provide DC operators
   with an easy and quick way to create a VN an NVO3 network and NVEs for
   any vDC design, to allocate TSs and assign TSs to the corresponding VN,
   NVO3 network, and to illustrate vDC topology and manage/configure
   individual elements in the vDC in a secure way.

                           Internet                    ^ Internet
                              ^                     +--+---+
                              |                     |  GW  |
                              |                     +--+---+
                              |                        |
                      +-------+--------+            +--+---+
                      |Firewall/Gateway+--- VPN-----+router|
                      +-------+--------+            +-+--+-+
                              |                       |  |
                           ...+....                   |..|
                  +-------: L3 VNa :---------+        LANs
                +-+-+      ........          |
                |LB |          |             |     Enterprise Site
                +-+-+          |             |
               ...+...      ...+...       ...+...
              : L2VNx :    : L2VNy :     : L2VNz :
               .......      .......       .......
                 |..|         |..|          |..|
                 |  |         |  |          |  |
               Web App.     Mail App.      VoIP App.

                        Provider DC Site

             Figure 2 - Virtual Data Center Abstraction View

5. Summary

   This document describes some general and potential NVO3 use cases in
   DCs. The combination of these cases will give operators the
   flexibility and capability to design more sophisticated cases for
   various cloud applications.

   DC services may vary, from infrastructure as a service (IaaS), to
   platform as a service (PaaS), to software as a service (SaaS).
   In these services, NVO3 virtual networks are just a portion of such services.

   NVO3 uses tunnel techniques to deliver VN NVO3 traffic over an IP DC physical
   infrastructure network.  A tunnel encapsulation protocol is
   necessary. An NVO3 tunnel may in turn be tunneled over other
   intermediate tunnels over the Internet or other WANs.

   An NVO3 virtual network in a DC may be accessed by external users in a
   secure way. Many existing technologies can help achieve this.

   NVO3 implementations may vary. Some DC operators prefer to use a
   centralized controller to manage tenant system reachability in a
   virtual network, while other operators prefer to use distribution
   protocols to advertise the tenant system location, i.e., NVE
   location. When a tenant network spans across multiple DCs and WANs,
   each network administration domain may use different methods to
   distribute the tenant system locations. Both control plane and data
   plane interworking are necessary.

6. Security Considerations

   Security is a concern. DC operators need to provide a tenant with a
   secured virtual network, which means one tenant's traffic is
   isolated from other tenants' traffic as well as from underlay
   networks. DC operators also need to prevent against a tenant
   application attacking their underlay DC network; further, they need
   to protect against a tenant application attacking another tenant
   application via the DC infrastructure network. For example, a tenant
   application attempts to generate a large volume of traffic to
   overload the DC's underlying network. An NVO3 solution has to
   address these issues.

7. IANA Considerations

   This document does not request any action from IANA.

8. References

8.1. Normative References

   [RFC7364] Narten, T., et al "Problem Statement: Overlays for Network
             Virtualization", RFC7364, October 2014.

   [RFC7365] Lasserre, M., Motin, T., and et al, "Framework for DC
             Network Virtualization", RFC7365, October 2014.

8.2. Informative References

   [IEEE802.1Q]  IEEE, "IEEE Standard for Local and metropolitan area
             networks -- Media Access Control (MAC) Bridges and Virtual
             Bridged Local Area", IEEE Std 802.1Q, 2011.

   [NVO3HYVR2NVE] Li, Y., et al, "Hypervisor to NVE Control Plane
             Requirements", draft-ietf-nvo3-hpvr2nve-cp-req-05, work in

   [NVO3ARCH] Black, D., et al, "An Architecture for Overlay Networks
             (NVO3)", draft-ietf-nvo3-arch-08, work in progress.

   [NVO3MCAST] Ghanwani, A., "Framework of Supporting Applications
             Specific Multicast in NVO3", draft-ghanwani-nvo3-app-
             mcast-framework-02, work in progress.

   [RFC1035] Mockapetris, P., "DOMAIN NAMES - Implementation and
             Specification", RFC1035, November 1987.

   [RFC3022] Srisuresh, P. and Egevang, K., "Traditional IP Network
             Address Translator (Traditional NAT)", RFC3022, January

   [RFC4301] Kent, S., "Security Architecture for the Internet
             Protocol", rfc4301, December 2005

   [RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
             Networks (VPNs)", RFC 4364, February 2006.

   [RFC7348]  Mahalingam,M., Dutt, D., ific Multicast in etc "VXLAN: A
             Framework for Overlaying Virtualized Layer 2 Networks over
             Layer 3 Networks", RFC7348 August 2014.

   [RFC7432]  Sajassi, A., Ed., Aggarwal, R., Bitar, N., Isaac, A. and
             J. Uttaro, "BGP MPLS Based Ethernet VPN", RFC7432,
             February 2015

   [RFC7637] Garg, P., and Wang, Y., "NVGRE: Network Virtualization
             using Generic Routing Encapsulation", RFC7637, Sept. 2015.

   [VRF-LITE] Cisco, "Configuring VRF-lite",


      Vinay Bannai
      2211 N. First St,
      San Jose, CA 95131
      Phone: +1-408-967-7784

      Ram Krishnan
      Brocade Communications
      San Jose, CA 95134
      Phone: +1-408-406-7890

      Kieran Milne
      Juniper Networks
      1133 Innovation Way
      Sunnyvale, CA 94089
      Phone: +1-408-745-2000


   Authors like to thank Sue Hares, Young Lee, David Black, Pedro
   Marques, Mike McBride, David McDysan, Randy Bush, Uma Chunduri, Eric
   Gray, David Allan, Joe Touch, and Olufemi Komolafe Komolafe, and Matthew Bocci
   for the review, comments, and suggestions.

 Authors' Addresses

   Lucy Yong
   Huawei Technologies

   Phone: +1-918-808-1918
   Linda Dunbar
   Huawei Technologies,
   5340 Legacy Dr.
   Plano, TX 75025 US

   Phone: +1-469-277-5840

   Mehmet Toy

   Phone : +1-856-792-2801
   E-mail :

   Aldrin Isaac
   Juniper Networks

   Vishwas Manral