Internet Engineering Task Force (IETF)                           L. Yong
Request for Comments: 8151                                     L. Dunbar
Category: Informational                                           Huawei
ISSN: 2070-1721                                                   M. Toy
                                                                Verizon
                                                               A. Isaac
                                                       Juniper Networks
                                                              V. Manral
                                                            Nano Sec Co
                                                               May 2017


  Use Cases for Data Center Network Virtualization Overlay Networks

Abstract

  This document describes Network Virtualization over Layer 3 (NVO3)
  use cases that can be deployed in various data centers and serve
  different data-center applications.

Status of This Memo

  This document is not an Internet Standards Track specification; it is
  published for informational purposes.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Not all documents
  approved by the IESG are a candidate for any level of Internet
  Standard; see Section 2 of RFC 7841.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  http://www.rfc-editor.org/info/rfc8151.
















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Copyright Notice

  Copyright (c) 2017 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
  (http://trustee.ietf.org/license-info) in effect on the date of
  publication of this document.  Please review these documents
  carefully, as they describe your rights and restrictions with respect
  to this document.  Code Components extracted from this document must
  include Simplified BSD License text as described in Section 4.e of
  the Trust Legal Provisions and are provided without warranty as
  described in the Simplified BSD License.

Table of Contents

  1. Introduction ....................................................3
     1.1. Terminology ................................................4
     1.2. NVO3 Background ............................................5
  2. DC with a Large Number of Virtual Networks ......................6
  3. DC NVO3 Virtual Network and External Network Interconnection ....6
     3.1. DC NVO3 Virtual Network Access via the Internet ............7
     3.2. DC NVO3 Virtual Network and SP WAN VPN Interconnection .....8
  4. DC Applications Using NVO3 ......................................9
     4.1. Supporting Multiple Technologies ...........................9
     4.2. DC Applications Spanning Multiple Physical Zones ..........10
     4.3. Virtual Data Center (vDC) .................................10
  5. Summary ........................................................12
  6. Security Considerations ........................................12
  7. IANA Considerations ............................................12
  8. Informative References .........................................13
  Acknowledgements...................................................14
  Contributors ......................................................15
  Authors' Addresses.................................................16
















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1.  Introduction

  Server 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 (DC) networks have limits in supporting cloud
  applications and multi-tenant networks [RFC7364].  The goal of data
  center Network Virtualization over Layer 3 (NVO3) networks is to
  decouple the communication among tenant systems from DC physical
  infrastructure networks and to allow one physical network
  infrastructure to:

  o  carry many NVO3 virtual networks and isolate the traffic of
     different NVO3 virtual networks on a physical network.

  o  provide independent address space in individual NVO3 virtual
     network such as Media Access Control (MAC) and IP.

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

  These characteristics of NVO3 virtual networks (VNs) help address the
  issues that cloud applications face in data centers [RFC7364].

  Hosts in one NVO3 VN may communicate with hosts in another NVO3 VN
  that is carried by the same physical network, or different physical
  network, via a gateway.  The use-case examples for the latter are as
  follows:

  1) DCs that migrate toward an NVO3 solution will be done in steps,
     where a portion of tenant systems in a VN are on virtualized
     servers while others exist on a LAN.

  2) many DC applications serve Internet users who are on different
     physical networks;

  3) some applications are CPU bound, such as Big Data analytics, and
     may not run on virtualized resources.

  The inter-VN policies are usually enforced by the gateway.

  This document describes general NVO3 VN use cases that apply to
  various data centers.  The use cases described here represent the DC
  provider's interests and vision for their cloud services.  The



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  document groups the use cases into three categories from simple to
  sophisticated in terms of implementation.  However, the
  implementation details of these use cases are outside the scope of
  this document.  These three categories are described below:

  o  Basic NVO3 VNs (Section 2).  All Tenant Systems (TSs) in the
     network are located within the same DC.  The individual networks
     can be either Layer 2 (L2) or Layer 3 (L3).  The number of NVO3
     VNs in a DC is much larger than the number that traditional VLAN-
     based virtual networks [IEEE802.1Q] can support.

  o  A virtual network that spans across multiple DCs and/or to
     customer premises where NVO3 virtual networks are constructed and
     interconnect other virtual or physical networks outside the DC.
     An enterprise customer may use a traditional carrier-grade 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
     gateways.  Three scenarios are described in Section 4:
     (1) supporting multiple technologies;
     (2) constructing several virtual networks as a tenant network; and
     (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 terminology defined in [RFC7365] and
  [RFC4364].  Some additional terms used in the document are listed
  here.

  ASBR:        Autonomous System Border Router.

  DC:          Data Center.

  DMZ:         Demilitarized Zone.  A computer or small subnetwork
               between a more-trusted internal network, such as a
               corporate private LAN, and an untrusted or less-trusted
               external network, such as the public Internet.

  DNS:         Domain Name Service [RFC1035].







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  DC Operator: An entity that is responsible for constructing and
               managing all resources in DCs, including, but not
               limited to, computing, storage, networking, etc.

  DC Provider: An entity that uses its DC infrastructure to offer
               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.

  NVO3:        Network Virtualization over Layer 3.  A virtual network
               that is implemented based on the NVO3 architecture.

  PE:          Provider Edge.

  SP:          Service Provider.

  TS:          A Tenant System, which can be instantiated on a physical
               server or virtual machine (VM).

  VRF-LITE:    Virtual Routing and Forwarding - LITE [VRF-LITE].

  VN:          Virtual Network

  VoIP:        Voice over IP

  WAN VPN:     Wide Area Network Virtual Private Network [RFC4364]
               [RFC7432].

1.2.  NVO3 Background

  An NVO3 virtual network is in a DC that is implemented based on the
  NVO3 architecture [RFC8014].  This architecture is often referred to
  as an overlay architecture.  The traffic carried by an NVO3 virtual
  network is encapsulated at a Network Virtualization Edge (NVE)
  [RFC8014] and carried by a tunnel to another NVE where the traffic is
  decapsulated and sent to a destination Tenant System (TS).  The NVO3
  architecture decouples NVO3 virtual networks from the DC physical
  network configuration.  The architecture uses common tunnels to carry
  NVO3 traffic that belongs to multiple NVO3 virtual networks.

  An NVO3 virtual network may be an L2 or L3 domain.  The network
  provides switching (L2) or routing (L3) capability to support host
  (i.e., TS) communications.  An NVO3 virtual network may be required
  to carry unicast traffic and/or multicast or broadcast/unknown-



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  unicast (for L2 only) traffic to/from TSs.  There are several ways to
  transport NVO3 virtual network Broadcast, Unknown Unicast, and
  Multicast (BUM) traffic [NVO3MCAST].

  An NVO3 virtual network provides communications among TSs in a DC.  A
  TS can be a physical server/device or a VM on a server end-device
  [RFC7365].

2.  DC with a Large Number of Virtual Networks

  A DC provider often uses NVO3 virtual networks for internal
  applications where each application runs on many VMs or physical
  servers and the provider requires applications to be segregated from
  each other.  A DC may run a larger number of NVO3 virtual networks to
  support many applications concurrently, where a traditional VLAN
  solution based on IEEE 802.1Q is limited to 4094 VLANs.

  Applications running on VMs may require a different quantity of
  computing resources, which may result in a computing-resource
  shortage on some servers and other servers being nearly idle.  A
  shortage of computing resources may impact application performance.
  DC operators desire VM or workload movement for resource-usage
  optimization.  VM dynamic placement and mobility results in frequent
  changes of the binding between a TS and an NVE.  The TS reachability
  update mechanisms should take significantly less time than the
  typical retransmission Timeout window of a reliable transport
  protocol such as TCP and Stream Control Transmission Protocol (SCTP),
  so that endpoints' transport connections won't be impacted by a TS
  becoming bound to a different NVE.  The capability of supporting many
  TSs in a virtual network and many virtual networks in a DC is
  critical for an NVO3 solution.

  When NVO3 virtual networks segregate VMs belonging to different
  applications, DC operators can independently assign MAC and/or IP
  address space to each virtual network.  This addressing is more
  flexible than requiring all hosts in all NVO3 virtual networks to
  share one address space.  In contrast, typical use of IEEE 802.1Q
  VLANs requires a single common MAC address space.

3.  DC NVO3 Virtual Network and External Network Interconnection

  Many customers (enterprises 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 NVO3 virtual network that provides connectivity to all
  the resources designated for a customer, and it allows the customer




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  to access the resources via a virtual GateWay (vGW).  WAN
  connectivity to the vGW can be provided by VPN technologies such as
  IPsec VPNs [RFC4301] and BGP/MPLS IP VPNs [RFC4364].

  If a virtual network spans multiple DC sites, one design using NVO3
  is to allow the network to seamlessly span 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 an intra-DC tunnel and inter-DC
  tunnel(s) can be stitched together to form an end-to-end tunnel
  between the pair of NVEs that are in different DC sites.  Both cases
  will form one NVO3 virtual network across multiple DC sites.

  Two use cases are described in the following sections.

3.1.  DC NVO3 Virtual Network Access via the Internet

  A customer can connect to an NVO3 virtual network via the Internet in
  a secure way.  Figure 1 illustrates an example of this case.  The
  NVO3 virtual network has an instance at NVE1 and NVE2, and the two
  NVEs are connected via an IP tunnel in the DC.  A set of TSs are
  attached to NVE1 on a server.  NVE2 resides on a DC Gateway device.
  NVE2 terminates the tunnel and uses the VN Identifier (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 Internal Border Gateway Protocol
  (IBGP) may be used for prefix advertisement.  The vGW provides IPsec
  functionality such as authentication scheme and encryption; IBGP
  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 the firewall and load-balancer (LB) can
     be performed by locally attached network appliance devices.

  o  If the NVO3 virtual network 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.







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  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.

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

          DC Provider Site

          Figure 1: DC Virtual Network Access via the Internet

3.2.  DC NVO3 Virtual 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 an
  NVO3 virtual network in a DC site.  The SP constructs a VPN for the
  enterprise customer.  Each enterprise site peers with an SP PE.  The
  DC provider and VPN SP can build an NVO3 virtual network 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].  Using the option "a" specified in [RFC4364] with VRF-LITE
  [VRF-LITE], both ASBRs, i.e., DC GW and SP PE, maintain a
  routing/forwarding table (VRF).  Using the option "b" specified in
  [RFC4364], the DC ASBR and SP ASBR do not maintain the VRF table;
  they only maintain the NVO3 virtual network and VPN identifier
  mappings, i.e., label mapping, and swap the label on the packets in
  the forwarding process.  Both option "a" and option "b" allow the se
  of NVO3 VNs and VPNs using their own identifiers, and two identifiers
  are mapped at the DC GW.  With the option "c" in [RFC4364], the VN



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  and VPN use the same identifier and both ASBRs perform the tunnel
  stitching, i.e., tunnel segment mapping.  Each option has pros and
  cons [RFC4364] and has been deployed in SP networks depending on the
  application requirements.  BGP is used in these options for route
  distribution between DCs and SP WANs.  Note that if the DC is the
  SP's DC, the DC GW and SP PE can be merged into one device that
  performs the interworking of the VN and VPN within an Autonomous
  System.

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

  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 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.  This section
  highlights some use cases for this goal.

4.1.  Supporting Multiple Technologies

  Servers deployed in a large DC are often installed at different
  times, and they 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 a standardized NVO3 encapsulation, some may not support any
  encapsulation, and some may support a documented encapsulation
  protocol (e.g., Virtual eXtensible Local Area Network (VXLAN)
  [RFC7348] and Network Virtualization using Generic Routing



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  Encapsulation (NVGRE) [RFC7637]) or proprietary encapsulations.  To
  construct a tenant network among these servers and the Top-of-Rack
  (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 has high CPU and
  memory consumption, which only makes sense to run on standalone
  servers; other software of the tenant may be good to run on VMs.
  However, provider DC infrastructure is configured to use NVO3 to
  connect VMs and VLANs [IEEE802.1Q] to physical servers.  The tenant
  network requires interworking between NVO3 and traditional VLAN.

4.2.  DC Applications Spanning Multiple Physical Zones

  A DC can be partitioned into multiple physical zones, with each zone
  having different access permissions and running 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 one or
  more security functions in a physical DMZ zone.  Each zone can be
  implemented by one NVO3 virtual network and the security functions in
  DMZ zone can be used to between two NVO3 virtual networks, i.e., two
  zones.  If network functions (NFs), especially the security functions
  in the physical DMZ, can't process encapsulated NVO3 traffic, the
  NVO3 tunnels have to be terminated for the NF to perform its
  processing on the application traffic.

4.3.  Virtual Data Center (vDC)

  An enterprise DC 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
  vDC over its physical DC infrastructure and offer a vDC 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 a firewall, DNS, LB,
  gateway, etc.




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  Figure 2 illustrates one such scenario at the 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.  An 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 DC
  provider site.

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

            DC Provider 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 it 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.





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

5.  Summary

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

  DC services may vary, NVO3 virtual networks make it possible to scale
  a large number of virtual networks in a DC and ensure the network
  infrastructure not impacted by the number of VMs and dynamic workload
  changes in a DC.

  NVO3 uses tunnel techniques to deliver NVO3 traffic over 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.

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 and is not leaked to the underlay
  networks.  Tenants are vulnerable to observation and data
  modification/injection by the operator of the underlay and should
  only use operators they trust.  DC operators also need to prevent a
  tenant application attacking their underlay DC networks; further,
  they need to protect 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.  This can be done by limiting
  the bandwidth of such communications.

7.  IANA Considerations

  This document does not require any IANA actions.







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8.  Informative References

  [IEEE802.1Q]   IEEE, "IEEE Standard for Local and metropolitan area
                 networks -- Media Access Control (MAC) Bridges and
                 Virtual Bridged Local Area Networks", IEEE Std
                 802.1Q-2011, DOI 10.1109/IEEESTD.2011.6009146.

  [NVO3MCAST]    Ghanwani, A., Dunbar, L., McBride, M., Bannai, V., and
                 R. Krishnan, "A Framework for Multicast in Network
                 Virtualization Overlays", Work in Progress,
                 draft-ietf-nvo3-mcast-framework-07, May 2016.

  [RFC1035]      Mockapetris, P., "Domain names - implementation and
                 specification", STD 13, RFC 1035,
                 DOI 10.17487/RFC1035, November 1987,
                 <http://www.rfc-editor.org/info/rfc1035>.

  [RFC3022]      Srisuresh, P. and K. Egevang, "Traditional IP Network
                 Address Translator (Traditional NAT)", RFC 3022,
                 DOI 10.17487/RFC3022, January 2001,
                 <http://www.rfc-editor.org/info/rfc3022>.

  [RFC4301]      Kent, S. and K. Seo, "Security Architecture for the
                 Internet Protocol", RFC 4301, DOI 10.17487/RFC4301,
                 December 2005,
                 <http://www.rfc-editor.org/info/rfc4301>.

  [RFC4364]      Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
                 Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364,
                 February 2006,
                 <http://www.rfc-editor.org/info/rfc4364>.

  [RFC7348]      Mahalingam, M., Dutt, D., Duda, K., Agarwal, P.,
                 Kreeger, L., Sridhar, T., Bursell, M., and C. Wright,
                 "Virtual eXtensible Local Area Network (VXLAN): A
                 Framework for Overlaying Virtualized Layer 2 Networks
                 over Layer 3 Networks", RFC 7348,
                 DOI 10.17487/RFC7348, August 2014,
                 <http://www.rfc-editor.org/info/rfc7348>.

  [RFC7364]      Narten, T., Ed., Gray, E., Ed., Black, D., Fang, L.,
                 Kreeger, L., and M. Napierala, "Problem Statement:
                 Overlays for Network Virtualization", RFC 7364,
                 DOI 10.17487/RFC7364, October 2014,
                 <http://www.rfc-editor.org/info/rfc7364>.






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  [RFC7365]      Lasserre, M., Balus, F., Morin, T., Bitar, N., and Y.
                 Rekhter, "Framework for Data Center (DC) Network
                 Virtualization", RFC 7365, DOI 10.17487/RFC7365,
                 October 2014,
                 <http://www.rfc-editor.org/info/rfc7365>.

  [RFC7432]      Sajassi, A., Ed., Aggarwal, R., Bitar, N., Isaac, A.,
                 Uttaro, J., Drake, J., and W. Henderickx, "BGP MPLS-
                 Based Ethernet VPN", RFC 7432, DOI 10.17487/RFC7432,
                 February 2015,
                 <http://www.rfc-editor.org/info/rfc7432>.

  [RFC7637]      Garg, P., Ed., and Y. Wang, Ed., "NVGRE: Network
                 Virtualization Using Generic Routing Encapsulation",
                 RFC 7637, DOI 10.17487/RFC7637, September 2015,
                 <http://www.rfc-editor.org/info/rfc7637>.

  [RFC8014]      Black, D., Hudson, J., Kreeger, L., Lasserre, M., and
                 T. Narten, "An Architecture for Data-Center Network
                 Virtualization over Layer 3 (NVO3)", RFC 8014,
                 DOI 10.17487/RFC8014, December 2016,
                 <http://www.rfc-editor.org/info/rfc8014>.

  [VRF-LITE]     Cisco, "Configuring VRF-lite",
                 <http://www.cisco.com/c/en/us/td/docs/switches/lan/
                 catalyst4500/12-2/31sg/configuration/guide/conf/
                 vrf.pdf>.

Acknowledgements

  The authors would 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, Olufemi Komolafe, Matthew Bocci,
  and Alia Atlas for the reviews, comments, and suggestions.

















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RFC 8151                      NVO3 Use Case                     May 2017


Contributors

  David Black
  Dell EMC
  176 South Street
  Hopkinton, MA 01748
  United States of America

  Email: [email protected]


  Vinay Bannai
  PayPal
  2211 N. First Street
  San Jose, CA 95131
  United States of America

  Phone: +1-408-967-7784
  Email: [email protected]


  Ram Krishnan
  Brocade Communications
  San Jose, CA 95134
  United States of America

  Phone: +1-408-406-7890
  Email: [email protected]


  Kieran Milne
  Juniper Networks
  1133 Innovation Way
  Sunnyvale, CA 94089
  United States of America

  Phone: +1-408-745-2000
  Email: [email protected]













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RFC 8151                      NVO3 Use Case                     May 2017


Authors' Addresses

  Lucy Yong
  Huawei Technologies
  Phone: +1-918-808-1918

  Email: [email protected]


  Linda Dunbar
  Huawei Technologies,
  5340 Legacy Drive
  Plano, TX 75025
  United States of America

  Phone: +1-469-277-5840
  Email: [email protected]


  Mehmet Toy
  Verizon

  Email: [email protected]


  Aldrin Isaac
  Juniper Networks
  1133 Innovation Way
  Sunnyvale, CA 94089
  United States of America

  Email: [email protected]


  Vishwas Manral
  Nano Sec Co
  3350 Thomas Rd.
  Santa Clara, CA
  United States of America

  Email: [email protected]










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