[IETFMIBS] Extending InetAddress(Type) for BGP Multicast VPNs

[Jeff Haas <[e-mail]>]

I am the current editor for the BGP MIB (draft-ietf-idr-bgp4-mibv2).  I've been approached recently about MIB representation of BGP Multicast VPNs (draft-ietf-l3vpn-2547bis-mcast-bgp).  After having spent some time discussing this with some people internally at Juniper, it seems like the BGP MIBv2 would handle a significant portion of representing MVPNs.  This is great, because much of the purpose of the structure of the new BGP MIB was to make it re-usable for other address families.

The one sticking point is the representation of MVPN reachability (prefixes, effectively).  The BGP MIB does the following:


    bgp4V2NlriPrefixType OBJECT-TYPE
        SYNTAX     InetAddressType
        MAX-ACCESS not-accessible


        STATUS     current
        DESCRIPTION
            "The type of the IP address prefix in the
             Network Layer Reachability Information field.
             The value of this object is derived from the
             appropriate value from the bgp4V2NlriAfi field.
             Where an appropriate InetAddressType is not
             available, the value of the object must be
             unknown(0)."
        ::= { bgp4V2NlriEntry 4 }

    bgp4V2NlriPrefix OBJECT-TYPE
        SYNTAX     InetAddress
        MAX-ACCESS not-accessible
        STATUS     current
        DESCRIPTION
            "An IP address prefix in the Network Layer
             Reachability Information field. This object
             is an IP address containing the prefix with
             length specified by bgp4V2NlriPrefixLen.
             Any bits beyond the length specified by
             bgp4V2NlriPrefixLen are zeroed."
        REFERENCE
            "RFC 4271, Section 4.3<http://tools.ietf.org/html/rfc4271#section-4.3>."
        ::= { bgp4V2NlriEntry 5 }

    bgp4V2NlriPrefixLen OBJECT-TYPE
        SYNTAX     InetAddressPrefixLength
        MAX-ACCESS not-accessible
        STATUS     current
        DESCRIPTION
            "Length in bits of the address prefix in
             the Network Layer Reachability Information field."
        ::= { bgp4V2NlriEntry 6 }


It would seem that the "relatively simple" method to extend this to MVPN would be to update the InetAddress(Type) textual conventions.

I am aware that by making that statement I have stepped into the dragon's maw.  Please be gentle. :-)

But more seriously, this seems to be a good fit for what this TC was intended to accomplish: Make MIB structure more generic and reusable.  How could we go about accomplishing the goal of re-using the BGP MIB for MVPN?

-- Jeff