Re: [Gen-art] Genart last call review of draft-ietf-idr-bgp-open-policy-18

[Alvaro Retana <[e-mail]>]

On December 21, 2021 at 8:01:21 PM, Gyan Mishra wrote:

Gyan:

Hi!  Happy New Year!

Thank you for the review!


...
> Summary: ... The new BGP role capabilities mismatch code 2 subcode 8
> discussed on ML seems to have multiple implementations deployed and one
> confined by Cisco. I agree that the authors should request a new subcode
> for the role mismatch notification.

To catch others up:  there is a confirmed case of squatting on the
assigned subcode.  A consultation on the next steps is open on the idr
list and will close tomorrow (Jan/5).

https://mailarchive.ietf.org/arch/msg/idr/RBD3Z9YIboudGAIeJLS8L--p4BU/


...
> Nits/editorial comments:
> Comment related to Gao-Rexford model. The Gao-Rexford Model only has 3 peer
> types North bound upstream Provider, Southbound Customer and lateral same
> tier level peer. With the role capabilities, RS and RS-Client is added which
> makes it slightly different but almost identical. In describing the role
> types would it make sense to have a graphical depiction of Gao-Redford model
> with the role capabilities on adjacent peers to help explain the role
> relationship for local and remote-as. Just an idea to help explain the role
> capabilities.

The role definitions are described in this document, not strictly
carried over from Gao-Rexford.  Nonetheless, a graphical description
on the roles defined here may make sense.  I'll leave it to the
authors to consider (if not too complicated).


> In the role correctness section scenario where the peer receives multiple
> role capabilities to send role mismatch notification. What if there is a
> timing issue and the multiple are received after the BGP open and peer is
> established possible sequence of events issue. Is it possible the peer may
> not get a mismatch notification if the peer establishes prior to getting a
> different capabilities where a mismatch or problem exists that is missed
> that could result in a route leak. I am thinking of possibly false positive
> or negative or negative during BGP open capabilities exchange

All capabilities are signaled in the OPEN, so there's no possibility
for receiving a Role Capability afterwards.


Alvaro.