[Docs] [txt|pdf] [Tracker] [Email] [Nits]



BESS Working Group                                           Yisong Liu
Internet Draft                                          Donald Eastlake
Intended status: Standards Track                    Huawei Technologies
Expires: December 10, 2018                                June 10, 2018



                EVPN Multicast Synchronization Enhancement
                draft-liu-bess-evpn-mcast-synch-enhance-00


Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   Internet-Drafts are draft documents valid for a maximum of six
   months and may be updated, replaced, or obsoleted by other documents
   at any time.  It is inappropriate to use Internet-Drafts as
   reference material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html

   This Internet-Draft will expire on December 10, 2018.

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.

Abstract



Liu, et al.              Expires December, 2018                [Page 1]


Internet-Draft   EVPN Multicast Synchronization Enhancement   June 2018


Ethernet Virtual Private Network (EVPN, RFC7432) solutions is becoming
prevalent in Data Centers, Data Center Interconnect (DCI) and Service
Provider VPN applications. In the scenario of multi-homing from a CE to
multiple PEs with links used in a single-active or all-active
redundancy mode, IGMP & MLD Join/Leave and PIM Join/RPT-Prune
synchronization procedures have been provided. This document specifies
an enhancement for IGMP/PIM signaling synchronization when using
different Ethernet tag encapsulation mode.

Table of Contents


   1. Introduction ................................................ 2
      1.1. Requirements Language................................... 3
      1.2. Terminology ............................................ 3
   2. Enhancement of IGMP/PIM Synchronization...................... 3
   3. BGP Encoding Improvement..................................... 4
      3.1. IGMP/PIM Join Synch Route............................... 4
      3.2. IGMP Leave Synch Route.................................. 5
      3.3. PIM RPT-Prune Synch Route............................... 7
   4. Security Considerations...................................... 8
   5. IANA Considerations ......................................... 8
   6. References .................................................. 8
      6.1. Normative References.................................... 8
      6.2. Informative References.................................. 8
   7. Acknowledgments ............................................. 8

1. Introduction

   Ethernet Virtual Private Network (EVPN [RFC7432]) solutions are
   becoming prevalent in Data Centers, Data Center Interconnect (DCI)
   and Service Provider VPN applications. In the scenario of multi-
   homing from a CE to multiple PEs with links used in a single-active
   or all-active redundancy mode, [EVPN-IGMP-MLD-PROXY] for IGMP&MLD
   Join/Leave and [EVPN-PIM-PROXY] for PIM Join/RPT-Prune
   synchronization procedures have been provided.

   However, there may be multiple ways for a CE to connect to PE,
   including ethernet tag termination and Q-in-Q termination. When
   IGMP/PIM synch routes are transmitted from one PE to another PE both
   multi-homing to the same CE, the appropriate VLAN tags should be
   included in the routes. This document specifies an improvement in
   IGMP/PIM synchronization process.






Liu, et al.              Expires December, 2018                [Page 2]


Internet-Draft   EVPN Multicast Synchronization Enhancement   June 2018


    1.1. Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

    1.2. Terminology

   CE: Customer Edge equipment

   EVPN: Ethernet Virtual Private Network

   Ethernet Segment (ES): When a customer site (device or network) is
   connected to one or more PEs via a set of Ethernet links, then that
   set of links is referred to as an 'Ethernet segment'.

   Ethernet Segment Identifier (ESI): A unique non-zero identifier that
   identifies an Ethernet segment is called an 'Ethernet Segment
   Identifier'.

   IGMP: Internet Group Management Protocol

   MLD: Multicast Listener Discovery

   PE: Provider Edge device

   PIM: Protocol Independent Multicast



2. Enhancement of IGMP/PIM Synchronization

   Consider the situation where one CE is dual-homed to two PEs. If the
   CE is connected through one VLAN and only one VLAN under the EVPN
   instance at the PE, the IGMP/PIM synch message can be directly sent
   from one PE to another PE with the ESI, which can represent the
   appropriate interface and can be encapsulated with the appropriate
   VLAN ID.

   However, there may be Ethernet tag termination and Q-in-Q
   termination on the PE interface connected to CE. When IGMP/PIM
   synchronization procedures are implemented between the two dual-
   homed PEs, the receiver PE cannot obtain the appropriate VLANs
   because of the information lacking in the IGMP/PIM synch route
   message. For example, PE1 and PE2 connect to the CE dual-homed for
   the same ES, and VLAN tag 1 to 10 termination is configured on the
   interface for CE connecting to PE1 and PE2. After receiving a


Liu, et al.              Expires December, 2018                [Page 3]


Internet-Draft   EVPN Multicast Synchronization Enhancement   June 2018


   IGMP/PIM join with VLAN tag 2 from the interface, PE1 sends a
   IGMP/PIM join synch route to PE2 with the ESI. But PE2 cannot get
   the VLAN tag information from the route, so that PE doesn't create
   the IGMP Join state accurately. It can only know the VLAN tag 1-10
   termination on the corresponding interface according to the [ES,BD].
   Especially Q-in-Q termination is configured on the interface for CE
   connecting to PE1 and PE2, outer and inner VLAN tag information will
   be both needed when IGMP/PIM synch routes are advertised between the
   dual-homed PE1 and PE2.

   This document extends the IGMP/PIM synch routes to solve the problem
    mentioned above. VLAN tag information from the original IGMP/PIM
    message is added in the synch routes NLRI as a part of the route
    key.



3. BGP Encoding Improvement

   This document extends the following routes defined in [EVPN-IGMP-
   MLD-PROXY] and [EVPN-PIM-PROXY]

   + Type 6 - IGMP/PIM Join Synch Route

   + Type 7 - IGMP Leave Synch Route

   + Type TBD - PIM RPT-Prune Synch Route

    3.1. IGMP/PIM Join Synch Route

   This document extends the IGMP/PIM Join Synch Route defined in
   [EVPN-PIM-PROXY] with new fields and Flags as shown in Figure 1.

             +----------------------------------------------+
             |  RD (8 octets)                               |
             +----------------------------------------------+
             |  Ethernet Segment Identifier (10 octets)     |
             +----------------------------------------------+
             |  Ethernet Tag ID  (4 octets)                 |
             +----------------------------------------------+
             |  Multicast Source Length (1 octet)           |
             +----------------------------------------------+
             |  Multicast Source Address (variable)         |
             +----------------------------------------------+
             |  Multicast Group Length (1 octet)            |
             +----------------------------------------------+
             |  Multicast Group Address (Variable)          |
             +----------------------------------------------+
             |  Originator Router Length (1 octet)          |



Liu, et al.              Expires December, 2018                [Page 4]


Internet-Draft   EVPN Multicast Synchronization Enhancement   June 2018


             +----------------------------------------------+
             |  Originator Router Address (variable)        |
             +----------------------------------------------+
             |  Flags (1 octet)                             |
             +----------------------------------------------+
             |  Upstream Router Length (1B)(optional)       |
             +----------------------------------------------+
             |  Upstream Router Addr (variable)(opt)        |
             +----------------------------------------------+
             |  Outer VLAN (2 octets)                       |
             +----------------------------------------------+
             |  Inner VLAN (2 octets)                       |
             +----------------------------------------------+


             Flags:

             0  1  2  3  4  5  6  7
             +--+--+--+--+--+--+--+--+
             |  |  | V| P|IE|v3|v2|v1|
             +--+--+--+--+--+--+--+--+


           Figure 1  IGMP/PIM Join Synch Route

   This route will be added the following extra fields:

   Outer VLAN Can be used for single layer VLAN tag and the outer layer
   of double layer VLAN tags, and can be 0. When 0, it means there is
   no VLAN tag information needed to be advertised.

   Inner VLAN Can be used for the inner layer of double layer VLAN
   tags, and can be 0. When 0, it means there is no inner VLAN.

   Flags: This field encodes Flags that are already relevant to IGMP
   and PIM. The following new Flag is defined:

   - Flag V: Indicates the Join Synch route carries VLAN tag
      information by the encapsulation of the received protocol packet.
      When V=1, the Outer VLAN and Inner VLAN fields are present in the
      route. Otherwise the two fields will not be present.

   Compared to [EVPN-PIM-PROXY] there are two additional fields
   considered part of the route key for BGP processing when Flag V is
   set 1.

    3.2. IGMP Leave Synch Route

   This document extends the IGMP Leave Synch Route defined in [EVPN-
   IGMP-MLD-PROXY] as shown in Figure 2


Liu, et al.              Expires December, 2018                [Page 5]


Internet-Draft   EVPN Multicast Synchronization Enhancement   June 2018


             +--------------------------------------------------+
             |  RD (8 octets)                                   |
             +--------------------------------------------------+
             |  Ethernet Segment Identifier (10 octets)         |
             +--------------------------------------------------+
             |  Ethernet Tag ID  (4 octets)                     |
             +--------------------------------------------------+
             |  Multicast Source Length (1 octet)               |
             +--------------------------------------------------+
             |  Multicast Source Address (variable)             |
             +--------------------------------------------------+
             |  Multicast Group Length (1 octet)                |
             +--------------------------------------------------+
             |  Multicast Group Address (Variable)              |
             +--------------------------------------------------+
             |  Originator Router Length (1 octet)              |
             +--------------------------------------------------+
             |  Originator Router Address (variable)            |
             +--------------------------------------------------+
             |  Leave Group Synchronization  # (4 octets)       |
             +--------------------------------------------------+
             |  Maximum Response Time (1 octet)                 |
             +--------------------------------------------------+
             |  Flags (1 octet)                                 |
             +--------------------------------------------------+
             |  Outer VLAN (2 octets)                           |
             +--------------------------------------------------+
             |  Inner VLAN (2 octets)                           |
             +--------------------------------------------------+


             Flags:

             0  1  2  3  4  5  6  7
             +--+--+--+--+--+--+--+--+
             |  |  |  | V|IE|v3|v2|v1|
             +--+--+--+--+--+--+--+--+


           Figure 2  IGMP Leave Synch Route

   This route will have the same extra fields as described in section
   3.1 added.

   Compared to [EVPN-IGMP-MLD-PROXY] there are two additional fields
   considered part of the route key for BGP processing when Flag V is
   set 1.






Liu, et al.              Expires December, 2018                [Page 6]


Internet-Draft   EVPN Multicast Synchronization Enhancement   June 2018


    3.3. PIM RPT-Prune Synch Route

   This document extends the PIM RPT-Prune Synch Route defined in
   [EVPN-PIM-PROXY] as shown in Figure 3

             +----------------------------------------------+
             |  RD (8 octets)                               |
             +----------------------------------------------+
             |  Ethernet Segment Identifier (10 octets)     |
             +----------------------------------------------+
             |  Ethernet Tag ID  (4 octets)                 |
             +----------------------------------------------+
             |  Multicast Source Length (1 octet)           |
             +----------------------------------------------+
             |  Multicast Source Address (variable)         |
             +----------------------------------------------+
             |  Multicast Group Length (1 octet)            |
             +----------------------------------------------+
             |  Multicast Group Address (Variable)          |
             +----------------------------------------------+
             |  Originator Router Length (1 octet)          |
             +----------------------------------------------+
             |  Originator Router Address (variable)        |
             +----------------------------------------------+
             |  Upstream Router Length (1B)(optional)       |
             +----------------------------------------------+
             |  Upstream Router Addr (variable)(opt)        |
             +----------------------------------------------+
             |  Flags (1 octet)                             |
             +----------------------------------------------+
             |  Outer VLAN (2 octets)                       |
             +----------------------------------------------+
             |  Inner VLAN (2 octets)                       |
             +----------------------------------------------+


             Flags:

             0  1  2  3  4  5  6  7
             +--+--+--+--+--+--+--+--+
             |  |  |  |  |  |  |  | V|
             +--+--+--+--+--+--+--+--+


           Figure 3  PIM RPT-Prune Synch Route

   This route will have the same Outer VLAN and Inner VLAN fields as
   described in section 3.1 added and an extra Flags field as IGMP/PIM
   Join Synch Route and IGMP Leave Synch Route to indicate the existing
   VLAN information.



Liu, et al.              Expires December, 2018                [Page 7]


Internet-Draft   EVPN Multicast Synchronization Enhancement   June 2018


   Compared to [EVPN-PIM-PROXY] there are two additional fields
   considered part of the route key for BGP processing when Flag V is
   set 1.

4. Security Considerations

   TBD

   For general EVPN Security Considerations, see [RFC7432].

5. IANA Considerations

   TBD

6. References

    6.1. Normative References

   [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC7432] A. Sajassi, Ed., R. Aggarwal, N. Bitar, A. Isaac, J.
             Uttaro, J. Drake, and W. Henderickx, "BGP MPLS-Based
             Ethernet VPN", RFC 7432, February 2015

   [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
             2119 Key Words", BCP 14, RFC 8174, May 2017

   [EVPN-IGMP-MLD-PROXY] Ali Sajassi, Samir Thoria, Keyur Patel, Derek
             Yeung, John Drake and Wen Lin, "IGMP and MLD Proxy for
             EVPN", March 2018, work-in-progress, draft-ietf-bess-evpn-
             igmp-mld-proxy-01.

   [EVPN-PIM-PROXY] J. Rabadan, Ed., J. Kotalwar, S. Sathappan, Z.
             Zhang and A. Sajassi, "PIM Proxy in EVPN Networks",
             October 2017, work-in-progress, draft-skr-evpn-bess-pim-
             proxy-01.

    6.2. Informative References

   TBD

7. Acknowledgments

   The authors would like to thank the following for their valuable
   contributions of this document:

   TBD



Liu, et al.              Expires December, 2018                [Page 8]


Internet-Draft   EVPN Multicast Synchronization Enhancement   June 2018


   Authors' Addresses

   Yisong Liu
   Huawei Technologies
   Huawei Bld., No.156 Beiqing Rd.
   Beijing  100095
   China

   Email: liuyisong@huawei.com


   Donald E. Eastlake, 3rd
   Huawei Technologies
   155 Beaver Street
   Milford, MA 01757 USA

   Phone: +1-508-333-2270
   Email: d3e3e3@gmail.com
































Liu, et al.              Expires December, 2018                [Page 9]


Html markup produced by rfcmarkup 1.127, available from https://tools.ietf.org/tools/rfcmarkup/