Subject: [i2rs] rtgdir Early Review of draft-ietf-i2rs-rib-model

From: Henning Rogge <[email-masked]>
Date: Mon, 31 Jul 2017 15:43:11 +0200

Hi,

I was asked to do an early review of the i2rs-rib-info-model...

I liked the comprehensive approach describing the RIB, including
tunnels, multi-topology routing (by using multiple RIBs) and routing
reactions (like drop/icmp-error).

I found a few things in the draft that in my opinion need a bit more work...

First it seems that Section 2.3 (Route) is a bit out of sync with the
BNF later in the document, it should at least mention matching the
source-IP address of the IP headers.

Second (if I read the BNF in Section 6 correctly), the match for a
route seems to be one of the list "ip address, MPLS label, MAC
address, interface". I think it should be possible to combine
"interface" or "mac address" with an IP address to restrict the focus
of a route, e.g. "match fe80::1 from interface X".

Last, I wonder if multicast routing needs more different types of
matchers, e.g. a match on the TTL of the IP packet to limit the range
of a multicast group.

There is also problem of multicast routing in MANETs (see RFC 6621)
which can use a hash-based duplicate detection to determine if it
forwards or drops a multicast packet. Would this be out of scope for
the draft?

Henning Rogge