Route Distinguisher Outbound Route Filter (RD-ORF) for BGP-4
draft-wang-idr-rd-orf-05

Versions: 00 01 02 03 04 05                                             
IDR Working Group                                                W. Wang
Internet-Draft                                                   A. Wang
Intended status: Standards Track                           China Telecom
Expires: May 3, 2021                                             H. Wang
                                                     Huawei Technologies
                                                               G. Mishra
                                                            Verizon Inc.
                                                               S. Zhuang
                                                                 J. Dong
                                                     Huawei Technologies
                                                        October 30, 2020


      Route Distinguisher Outbound Route Filter (RD-ORF) for BGP-4
                        draft-wang-idr-rd-orf-04

Abstract

   This draft defines a new Outbound Route Filter (ORF) type, called the
   Route Distinguisher ORF (RD-ORF).  RD-ORF is applicable when the
   routers do not exchange VPN routing information directly (e.g.
   routers in single-domain connect via Route Reflector, or routers in
   Option B/Option AB/Option C cross-domain scenario).

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
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   This Internet-Draft will expire on May 3, 2021.

Copyright Notice

   Copyright (c) 2020 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



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   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions used in this document . . . . . . . . . . . . . .   4
   3.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   4.  RD-ORF Encoding . . . . . . . . . . . . . . . . . . . . . . .   5
   5.  Application in single-domain scenario . . . . . . . . . . . .   7
     5.1.  Addition of RD-ORF entries  . . . . . . . . . . . . . . .   7
       5.1.1.  Operation process of RD-ORF mechanism on source PE  .   7
       5.1.2.  Operation process of RD-ORF mechanism on RR . . . . .   9
       5.1.3.  Operation process of RD-ORF mechanism on target PE  .   9
     5.2.  Withdraw of RD-ORF entries  . . . . . . . . . . . . . . .   9
   6.  Applications in cross-domain scenarios  . . . . . . . . . . .  10
     6.1.  Application in Option B/Option AB cross-domain scenario .  10
     6.2.  Application in Option C cross-domain scenario . . . . . .  11
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  12
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  13
   9.  Acknowledgement . . . . . . . . . . . . . . . . . . . . . . .  13
   10. Normative References  . . . . . . . . . . . . . . . . . . . .  13
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  14

1.  Introduction

   With the rapid growth of network scale, Route Reflector is introduced
   in order to reduce the network complexity.  Routers in the same
   Autonomous System only need to establish iBGP session with RR to
   transmit routes.

   In VPN scenario shown in Figure 1, PE1 - PE4 establish IBGP sessions
   with RR to ensure the routes can be transmitted within AS100, where
   PE1 and PE3 maintain VRFs of VPN1 and VPN2, PE2 maintains VPN1's VRF
   and PE4 maintains VPN2's VRF.  RR don not maintain any VRFs.











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              +----------------------------------------------+
              |                                              |
              |                                              |
              |   +---------+                  +---------+   |
              |   |   PE1   |                  |   PE4   |   |
              |   +---------+                  +---------+   |
              |      VPN1    \                /   VPN2       |
              |      VPN2      \+---------+ /                |
              |                 |         |                  |
              |                 |   RR    |                  |
              |                 |         |                  |
              |                 +---------+ \                |
              |                /              \              |
              |   +---------+/                 +---------+   |
              |   |   PE2   |                  |   PE3   |   |
              |   +---------+                  +---------+   |
              |      VPN1                         VPN1       |
              |                    AS 100         VPN2       |
              +----------------------------------------------+


                         Figure 1: Single-domain scenario

   When the VRF of VPN1 in PE1 overflows, due to PE1 and other PEs are
   not iBGP neighbors, BGP Maximum Prefix Features cannot work, so the
   problem on PE2 cannot be known.

   Now, there are several solutions can be used to alleviate this
   problem:

   o  Route Target Constraint (RTC) as defined in [RFC4684]

   o  Address Prefix ORF as defined in [RFC5292]

   o  PE-CE edge peer Maximum Prefix

   o  Configure the Maximum Prefix for each VRF on edge nodes

   However, there are limitations to existing solutions:

   1) Route Target Constraint

   RTC can only filter the VPN routes from the uninterested VRFs, if the
   "trashing routes" come from the interested VRF, filter on RTs will
   erase all prefixes from this VRF.

   2) Address Prefix ORF




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   Using Address Prefix ORF to filter VPN routes need to pre-
   configuration, but it is impossible to know which prefix may cause
   overflow in advance.

   3) PE-CE edge peer Maximum Prefix

   This mechanism can only protect the edge between PE-CE, it can't be
   deployed within PE that peered via RR.  Depending solely on the edge
   protection is dangerous, because if only one of the edge points being
   comprised/error-configured/attacked, then all of PEs within domain
   are under risk.

   4) Configure the Maximum Prefix for each VRF on edge nodes

   When a VRF overflows, it stops the import of routes and log the extra
   VPN routes into its RIB.  However, PEs should parse the BGP updates.
   These processes will cost CPU cycles and further burden the
   overflowing PE.

   This draft defines a new ORF-type, called the Route Distinguisher ORF
   (RD-ORF).  Using RD-ORF mechanism, VPN routes of a VPN can be
   controlled based on source RD and originator.  This mechanism is
   event-driven and does not need to be pre-configured.  When a VRF of a
   router overflows, the router will find out the main source address
   and RD of VPN routes in this VRF, and send a RD-ORF to its BGP peer
   that carrys the RD and the source address.  If a BGP speaker receives
   a RD-ORF from its BGP peer, it will filter the VPN routes it tends to
   send according to the RD-ORF entry.

   RD-ORF is applicable when the routers do not exchange VPN routing
   information directly (e.g. routers in single-domain connect via Route
   Reflector, or routers in Option B/Option AB/Option C cross-domain
   scenario).

2.  Conventions used in this document

   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.  Terminology

   The following terms are defined in this draft:

   o  RD: Route Distinguisher, defined in [RFC4364]

   o  ORF: Outbound Route Filter, defined in [RFC5291]




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   o  AFI: Address Family Identifier, defined in [RFC4760]

   o  SAFI: Subsequent Address Family Identifier, defined in [RFC4760]

   o  EVPN: BGP/MPLS Ethernet VPN, defined in [RFC7432]

   o  RR: Router Reflector, provides a simple solution to the problem of
      IBGP full mesh connection in large-scale IBGP implementation.

   o  VRF: Virtual Routing Forwarding, a virtual routing table based on
      VPN instance.

4.  RD-ORF Encoding

   In this draft, we defined a new ORF type called Route Distinguisher
   Outbound Route Filter (RD-ORF).  The ORF entries are carried in the
   BGP ROUTE-REFRESH message as defined in [RFC5291].  A BGP ROUTE-
   REFRESH message can carry one or more ORF entries, and MUST be
   regenerated when it is tended to be sent to other BGP peers.  The
   ROUTE-REFRESH message which carries ORF entries contains the
   following fields:

   o  AFI (2 octets)

   o  SAFI (1 octet)

   o  When-to-refresh (1 octet): the value is IMMEDIATE or DEFER

   o  ORF Type (1 octet)

   o  Length of ORF entries (2 octets)

   A RD-ORF entry contains a common part and type-specific part.  The
   common part is encoded as follows:

   o  Action (2 bits): the value is ADD, REMOVE or REMOVE-ALL

   o  Match (1 bit): the value is PERMIT or DENY

   o  Reserved (5 bits)

   RD-ORF also contains type-specific part.  The encoding of the type-
   specific part is shown in Figure 2.








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             +-----------------------------------------+
             |                                         |
             |          Sequence (4 octets)            |
             |                                         |
             +-----------------------------------------+
             |                                         |
             |      Route Distinguisher (8 octets)     |
             |                                         |
             +-----------------------------------------+
             |                                         |
             |Source Address sub-TLV (4,6 or 16 octets)|
             |                                         |
             +-----------------------------------------+


                        Figure 2: RD-ORF type-specific encoding

   o  Sequence: identifying the order in which RD-ORF is generated

   o  Route Distinguisher: distinguish the different user routes.  The
      RD-ORF filters the VPN routes it tends to send based on Route
      Distinguisher.

   o  Source Address sub-TLV: the source address is TLV format, which
      contains the following sub-TLVs:

      *  In single-domain or Option C cross-domain scenario, NEXT_HOP
         attribute is fixed during routing transmission, so it can be
         used as source address.

            Type = 1, Length = 4 or 16 octets, value = NEXT_HOP.

      *  In Option B or Option AB cross-domain scenario, NEXT_HOP
         attribute may be changed by ASBRs and cannot be used as the
         source address.  The originator can be traced by the Route
         Origin Community in BGP (as defined in Section 5 of [RFC4360]).

            Type = 2, Length = 6 octets, value = the value field of
            Route Origin Community.

   Note that if the Action component of an ORF entry specifies REMOVE-
   ALL, the ORF entry does not include the type-specific part.

   When the BGP ROUTE-REFRESH message carries RD-ORF entries, it must be
   set as follows:

   o  The ORF-Type MUST be set to RD-ORF.




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   o  The AFI MUST be set to IPv4, IPv6, or Layer 2 VPN (L2VPN).

   o  If the AFI is set to IPv4 or IPv6, the SAFI MUST be set to MPLS-
      labeled VPN address.

   o  If the AFI is set to L2VPN, the SAFI MUST be set to BGP EVPN.

   o  The Match field MUST be equal to DENY.

5.  Application in single-domain scenario

5.1.  Addition of RD-ORF entries

   The operation of RD-ORF mechanism on each device is independent, each
   of them makes a local judgement to determine whether it needs to send
   RD-ORF to its peers.

   In general, every VRF on PE is configured a Maximum Prefix, the
   trigger of RD-ORF mechanism can be set as the number of VPN routes in
   VRF reach 80% of the Maximum Prefix.  For RR, it doesn't have VRF and
   the machanism can be triggered by other conditions, such as the RR's
   memory/CPU utilization reaches 80%.

   When the RD-ORF mechanism is triggered, the device must send an alarm
   information to network operators.

5.1.1.  Operation process of RD-ORF mechanism on source PE

   In scenario shown in Figure 1, when the VRF of VPN1 in PE1 overflows,
   PE1 will do analysis and calculation locally to find out the main
   source of VPN routes in this VRF, assuming it is PE3.  Then, PE1 will
   resolve the host address and corresponding RD of VPN routes from BGP
   UPDATE message, and generate a BGP ROUTE-REFRESH message contains a
   RD-ORF entry, and send it to RR.  The message contains the following
   fields:

   o  AFI is set to IPv4 , IPv6 or L2 VPN

   o  SAFI is set to "MPLS-labeled VPN address" or "BGP EVPN"

   o  When-to-refresh is set to IMMEDIATE

   o  ORF Type is set to RD-ORF

   o  Length of ORF entries depends on the type of Source Address sub-
      TLV (21, 23 or 33 octets)

   o  Action is set to ADD



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   o  Match is set to DENY

   o  Sequence is set to 1

   o  Route Distinguisher is set to RD1

   o  Source Address sub-TLV is set to PE3's host address

   It noted that the Sequence can uniquely identifies an RD-ORF entry.
   All VRFs share the sequence field, and the corresponding sequence of
   RD-ORF sent by each VRF will be recorded on the device.

   Sometimes, several VRFs in a PE may import VPN routes carries the
   same RT, as shown in Figure 3.

 +-----------------------------------------------+
 |      +--------+                               |
 |      |   RR   |                               |
 |      +--------+                               |
 |          |                                    |
 |          |                                    |
 |          |                                    |
 |          |                                    |
 |          |                                    |
 |      +--------+  VRF1 RT-import: RT1 RT3(RD3) |
 |      |   PE   |  VRF2 RT-import: RT2 RT3(RD3) |
 |      +--------+  VRF3 RT-import: RT3(RD3)     |
 |                  VRF4 RT-import: RT4          |
 |                                               |
 |                     AS 100                    |
 +-----------------------------------------------+

            Figure 3: The scenario of several VRFs in a PE import VPN routes carries the same RT

   In this scenario, VRF1, VRF2 and VRF3 import VPN routes carries RT3,
   which contains RD3.  VRF1, VRF2 and VRF3 have different maximum
   prefix.  When the VPN routes carrying RT3 cause the overflow of VRF3,
   PE will send a BGP ROUTE-REFRESH message containing a RD-ORF entry to
   RR, which Route Distinguisher field is equal to RD3.  RR will stop
   sending associated VPN routes to PE.  However, this will cause VRF1
   to fail to receive VPN routes containing RD3.

   The local determination of the PE can be used to inhibit the PE from
   sending RD-ORF entries.  When the resources of the device are not
   exhausted, only prevent the overflowed VRF from importing related VPN
   routes without sending RD-ORF, unless all the VRFs that import the RD
   overflow.




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5.1.2.  Operation process of RD-ORF mechanism on RR

   When RR receives the ROUTE-REFRESH message, it checks <AFI/SAFI, ORF-
   Type, Sequence, Route Distinguisher, Source Address sub-TLV> to find
   whether it received the latest entry or not.  If not, RR will discard
   the entry; otherwise, RR will add the RD-ORF entry into its Adj-RIB-
   out.

   Before sending a VPN route toward PE1, RR will check its Adj-RIB-out
   and find there is a filter associated with <RD1, PE3's host address>.
   Then, RR will stop sending that VPN route to PE1.

   If the processing capacity of RR reaches the limit (e.g.  RR's
   memory/CPU utilization reaches 80%), RR will find out the peer that
   sends the most routing entries to it, assuming it is PE3.  Then, RR
   will generate a BGP ROUTE-REFRESH message contains a RD-ORF entry
   based on the result of calculation, and send it to PE3.

5.1.3.  Operation process of RD-ORF mechanism on target PE

   After receiving the ROUTE-REFRESH message that carries a RD-ORF
   entry, PE3 will check if it receives the latest entry.  If not, PE3
   will discard it; otherwise, PE3 will add the RD-ORF entry into its
   Adj-RIB-out.

   Before sending a VPN route toward RR, PE3 will check its Adj-RIB-out
   and find the RD-ORF entry prevent it from sending VPN route which
   carries RD1 to RR.  Then, PE3 will stop sending that VPN route.

   The BGP Maximum Prefix Features can be configured to protect PE-CE
   peering at the edge.  Therefore, in general, CEs will not cause the
   overflow of PEs.  If the boundary protection measures fail and cause
   the overflow, the PE can calculate and find the CEs in corresponding
   VRF, and break down the associated BGP sessions.

5.2.  Withdraw of RD-ORF entries

   When the RD-ORF mechanism is triggered, the alarm information will be
   generated and sent to the network operators.  Operators should
   manually configure the network to resume normal operation.  Due to
   devices can record the RD-ORF entries sent by each VRF, operators can
   find the entries needs to be withdrawn, and trigger the withdraw
   process as described in [RFC5291] manually to delete them on RR/ASBR/
   target PE after network recovery.







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6.  Applications in cross-domain scenarios

6.1.  Application in Option B/Option AB cross-domain scenario

   The Option B/Option AB cross-domain scenario is shown in Figure 4:

   +--------------------------+             +--------------------------+
   |                          |             |                          |
   |                          |             |                          |
   |   +---------+            |             |            +---------+   |
   |   |   PE1   |            |             |            |   PE3   |   |
   |   +---------+            |             |            +---------+   |
   |      VPN1    \           |             |           /   VPN1       |
   |      VPN2      \+---------+    EBGP   +---------+/     VPN2       |
   |                 |         |           |         |                 |
   |                 |  ASBR1  |-----------|  ASBR2  |                 |
   |                 |         |           |         |                 |
   |                 +---------+           +---------+                 |
   |                /         |             |         \                |
   |   +---------+/           |             |           \+---------+   |
   |   |   PE2   |            |             |            |   PE4   |   |
   |   +---------+            |             |            +---------+   |
   |      VPN1                |             |               VPN2       |
   |           AS1            |             |           AS2            |
   +--------------------------+             +--------------------------+

              Figure 4: The Option B/Option AB cross-domain scenario

   In Option B cross-domain scenario, PE1 - PE4 are responsible for
   maintaining VPN routing information in AS1 and AS2.  There is a
   direct link between ASBR1 and ASBR2 via EBGP.  In AS1, PE1 and PE2
   establish IBGP sessions with ASBR1 to ensure the routes can be
   transmitted in AS1.  In AS2, PE3 and PE4 establish IBGP session with
   ASBR2.

   Due to the maintenance of VPN routes is only done by PEs.  ASBRs
   cannot know whether the PEs' ability to handle VPN routes has reached
   the upper limit or not, so it needs the RD-ORF to control the number
   of routes.

   Assume that PE1 - PE4 can transmit VPN routes through the network
   architecture shown in Figure 4.  When the VRF of VPN1 in PE1
   overflows, the RD-ORF mechanism will be implemented as follows:

   1) PE1 will check and find out the main source of VPN routes in this
   VRF is PE3.  Then, PE1 will resolve the host address and
   corresponding RD from BGP UPDATE message, and generate a BGP ROUTE-
   REFRESH message contains an RD-ORF entry, and send it to ASBR1.



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   2) When ASBR1 receives the ROUTE-REFRESH message, it checks whether
   it receives the latest RD-ORF entry.  If not, ASBR1 will discard the
   entry; Otherwise, ASBR1 will add the RD-ORF entry into its Adj-RIB-
   out.

   Before sending a VPN route toward PE1, RR will check its Adj-RIB-out
   and find there is a filter associated with <RD1, PE3's host address>.
   Then, ASBR1 will stop sending that VPN route.

   Besides, ASBR1 will locally determine if it needs to send an RD-ORF
   entry to ASBR2.  The judgment criteria refers to Section 5.1.2.

   3) If ASBR2/PE3 receives the RD-ORF entry, it will repeat the above
   process.

   When the RD-ORF mechanism is triggered, network operators need to
   manually configure the network to return to resume normal operation.
   The withdraw of RD-ORF entries refers to Section 5.2.

   In Option AB cross-domain scenario, ASBRs maintain a VRF for a VPN.
   However, due to VPN routes in all VRFs use the same BGP session,
   ASBRs cannot prevent the overflow of a certain VRF by breaking down a
   BGP session.  The operation process of RD-ORF is similar to that in
   Option B scenario.

6.2.  Application in Option C cross-domain scenario

   The Option C cross-domain scenario is shown in Figure 5:























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                                    MP-EBGP
                +----------------------------------------+
                |                                        |
   +------------+------------+              +------------+------------+
   |       +----+----+       |              |       +----+----+       |
   |       |         |       |              |       |         |       |
   |  +----+   RR1   +----+  |              |  +----+   RR2   +----+  |
   |  |    |         |    |  |              |  |    |         |    |  |
   |  |    +---------+    |  |              |  |    +---------+    |  |
   |  |                   |  |              |  |                   |  |
   |  |IBGP           IBGP|  |              |  |IBGP           IBGP|  |
   |  |                   |  |              |  |                   |  |
 +-+--+----+         +----+--+-+          +-+--+----+         +----+--+-+
 |         |         |         |          |         |         |         |
 |   PE1   |         |  ASBR1  |----------|  ASBR2  |         |   PE2   |
 |         |         |         |          |         |         |         |
 +-+-------+   AS1   +-------+-+          +-+-------+   AS2   +-------+-+
   +-------------------------+              +-------------------------+

            Figure 5: The Option C cross-domain scenario

   In this scenario, PE1 and PE2 are responsible for maintaining VPN
   routing information in AS1 and AS2.  In order to reduce the
   complexity that full-mesh brings to the network, RR1 and RR2
   establish MP-EBGP session to transmit labeled routes.  In AS1, PE1
   and ASBR1 establish IBGP session with RR1 to ensure the routes can be
   transmitted in AS1.  In AS2, PE2 and ASBR2 establish IBGP session
   with RR2.

   Due to the maintenance of VPN routes is only done by PEs.  RRs cannot
   know whether the PEs' ability to handle VPN routes has reached the
   upper limit or not, so it needs the RD-ORF to control the number of
   routes.

   The operating mechanism of RD-ORF is similar to the description in
   Section 6.1.

7.  Security Considerations

   A BGP speaker will maintain the RD-ORF entries in Adj-RIB-out, this
   behavior consumes its memory and compute resources.  To avoid the
   excessive consumption of resources, [RFC5291] specifies that a BGP
   speaker can only accept ORF entries transmitted by its interested
   peers.







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8.  IANA Considerations

   This document defines a new Outbound Route Filter type - Route
   Distinguisher Outbound Route Filter (RD-ORF).  The code point is from
   the "BGP Outbound Route Filtering (ORF) Types".  It is recommended to
   set the code point of RD-ORF to 66.

   IANA is requested to allocate one code point for Source Address sub-
   TLV for RD-ORF.

   This document defines the following new RD-ORF sub-TLV types, which
   should be reflected in the Source Address sub-TLV for RD-ORF Code
   Point registry:

+----+-------------------------------------------------------------------+
|Type| Description                                                       |
+----+-------------------------------------------------------------------+
|  1 | Next hop Source Address sub-TLV                                   |
+----+-------------------------------------------------------------------+
|  2 | Route Origin Community Source Address sub-TLV                     |
+----+-------------------------------------------------------------------+

9.  Acknowledgement

   Thanks Robert Raszuk, Jim Uttaro, Jakob Heitz, Jeff Tantsura, Rajiv
   Asati, John E Drake and Gert Doering for their valuable comments on
   this draft.

10.  Normative References

   [I-D.ietf-bess-evpn-inter-subnet-forwarding]
              Sajassi, A., Salam, S., Thoria, S., Drake, J., and J.
              Rabadan, "Integrated Routing and Bridging in EVPN", draft-
              ietf-bess-evpn-inter-subnet-forwarding-11 (work in
              progress), October 2020.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC4360]  Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended
              Communities Attribute", RFC 4360, DOI 10.17487/RFC4360,
              February 2006, <https://www.rfc-editor.org/info/rfc4360>.

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



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   [RFC4684]  Marques, P., Bonica, R., Fang, L., Martini, L., Raszuk,
              R., Patel, K., and J. Guichard, "Constrained Route
              Distribution for Border Gateway Protocol/MultiProtocol
              Label Switching (BGP/MPLS) Internet Protocol (IP) Virtual
              Private Networks (VPNs)", RFC 4684, DOI 10.17487/RFC4684,
              November 2006, <https://www.rfc-editor.org/info/rfc4684>.

   [RFC4760]  Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
              "Multiprotocol Extensions for BGP-4", RFC 4760,
              DOI 10.17487/RFC4760, January 2007,
              <https://www.rfc-editor.org/info/rfc4760>.

   [RFC5291]  Chen, E. and Y. Rekhter, "Outbound Route Filtering
              Capability for BGP-4", RFC 5291, DOI 10.17487/RFC5291,
              August 2008, <https://www.rfc-editor.org/info/rfc5291>.

   [RFC5292]  Chen, E. and S. Sangli, "Address-Prefix-Based Outbound
              Route Filter for BGP-4", RFC 5292, DOI 10.17487/RFC5292,
              August 2008, <https://www.rfc-editor.org/info/rfc5292>.

   [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, <https://www.rfc-editor.org/info/rfc7432>.

Authors' Addresses

   Wei Wang
   China Telecom
   Beiqijia Town, Changping District
   Beijing, Beijing  102209
   China

   Email: wangw36@chinatelecom.cn


   Aijun Wang
   China Telecom
   Beiqijia Town, Changping District
   Beijing, Beijing  102209
   China

   Email: wangaj3@chinatelecom.cn








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Internet-Draft                   RD-ORF                     October 2020


   Haibo Wang
   Huawei Technologies
   Huawei Building, No.156 Beiqing Rd.
   Beijing, Beijing  100095
   China

   Email: rainsword.wang@huawei.com


   Gyan S. Mishra
   Verizon Inc.
   13101 Columbia Pike
   Silver Spring  MD 20904
   United States of America

   Phone: 301 502-1347
   Email: gyan.s.mishra@verizon.com


   Shunwan Zhuang
   Huawei Technologies
   Huawei Building, No.156 Beiqing Rd.
   Beijing, Beijing  100095
   China

   Email: zhuangshunwan@huawei.com


   Jie Dong
   Huawei Technologies
   Huawei Building, No.156 Beiqing Rd.
   Beijing, Beijing  100095
   China

   Email: jie.dong@huawei.com
















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