Subject: [MRT] draft-ietf-ospf-mrt-00 & draft-ietf-rtgwg-mrt-frr-architecture-05 [OSPF Extensions to Support Maximally Redundant Trees & An Architecture for IP/LDP Fast-Reroute Using Maximally Redundant Trees]

From: "Anil Kumar S N (VRP Network BL)" <[email-masked]>
Date: Tue, 28 Apr 2015 07:12:59 +0000

Hi Authors,

     I feel MRT-RED and MRT-BLUE MT-ID should be per MT.
When MRT protection is desired on the network with multiple MT, How do we have a unique MRT-BLUE and MRT-RED MT-ID since MT-ID is a global to system?
Finalizing on MT-ID values for Red and Blue per MT is a open question I feel :)
Please let me know your opinion.

We need following changes in OSPF extension on MRT if we desired to support MRT on multiple MT network.
5.3<https://tools.ietf.org/html/draft-ietf-ospf-mrt-00#section-5.3>.  MRT Profile TLV in Router Information LSA
       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              Type             |           Length              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      | Profile ID(1) |GADAG Priority | Primary MT-ID |   Reserved    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                         ..............                        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      | Profile ID(n) |GADAG Priority | Primary MT-ID |   Reserved    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      TYPE:  TBA-MRT-OSPF-1 (To Be Allocated by IANA)
      LENGTH: 4 * (number of Profiles)
      Profile ID :  1 byte
             GADAG Priority: 1 byte
             Primary MT-ID : 1 byte

6.1<https://tools.ietf.org/html/draft-ietf-ospf-mrt-00#section-6.1>.  MRT-Ineligible Link sub-TLV

       0                   1                   2                   3

       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1

      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      |              Type             |          Length               |

      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      | Primary MT-ID |                   Reserved                    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      TYPE:  TBA-MRT-OSPF-2 in OSPFv2 Extended Link TLV

             TBA-MRT-OSPF-3 in OSPFv3 Router-Link TLV

             (To Be Allocated by IANA)

      LENGTH: 4 * (number of MT's on which this link is Ineligible)

      Primary MT-ID : 1 byte

                        MRT-Ineligible Link sub-TLV

Thanks & Regards
Anil S N

"Be liberal in what you accept, and conservative in what you send" - Jon Postel