[Idr] Use of BGP for Opaque Signaling

[Robert Raszuk <[e-mail]>]

​Petr, Eben,

I have few questions and comments to your proposal.

- The draft ​attempts to reuse BGP mechanism for p2mp distribution of
opaque information. That alone is not a bad thing :) However when you make
reference to BGP-LS it needs to be observed that BGP-LS is not position to
directly impact routing (ie content of RIB and FIBs) unlike one of the use
cases described in your draft Intro paragraph. That means that unlike
BGP-LS it must co-exist with routing BGP on the same BGP speakers.

Here I would like to bring back my proposal to define new port for
Transport Instance BGP https://tools.ietf.org/html/draft-raszuk-ti-bgp-01
which at the time of discussion was supposed to be shortly addressed by
dynamic port allocations of multisessions which to the best of my knowledge
never happened.

So first comment is that if we go with reusing BGP-4 for this type of
signalling let's enforce it's early separation from "classic" BGP.

- Second comment is related to the scope of use. If the scope is private -
let's perhaps enforce it more explicitly such that by the spec it is
illegal AFI/SAFI pair in the public Internet. For example by stating that
it is illegal to have non private AS in the AS_PATH of such UPDATE msg.

- Third the draft states that there is no new security implications .. well
if the scope is non private I am afraid that is no the case. As you have
seen (and still seeing) securing BGP UPDATE MSG is MP_REACH content
dependent. If content is free form I am afraid it will be rather hard to
secure it well :)

- Last as opaque value container you are defining an transitive attribute ?
Is the intention to use this attribute in existing AFI/SAFIs as well ?
Otherwise if not why do you need this to be transitive if capability
negotiation already may implicitly define it's support by new AFI/SAFI.

Cheers,
R.

PS.

> There is an ongoing discussion around avoiding NLRI (key) collisions.

Where is such discussion taking place ? Shouldn't IDR be perhaps in the
loop a bit :)