Hi Jeff,
I'd be fine with the text below on BFD echo in the discussion section.
Regards,
Reshad.
On 2018-10-29, 11:36 AM, "Jeffrey Haas" <jh...@pfrc.org> wrote:
Reshad,
On Fri, Oct 26, 2018 at 06:32:26PM +0000, Reshad Rahman (rrahman) wrote:
>On 2018-10-25, 11:38 AM, "Jeffrey Haas" <jh...@pfrc.org> wrote:
> > The draft I had previously worked on with Xiao Min discussing
probing using
> > BFD Echo had the concept of probes that would happen wherein the
session is
> > not torn down. The example carries similarly with the "send
occasional".
>
> <RR> We discussed use of echo at IETF102. The large-packets draft mentions
> that echo can only be used for single-hop, hence the need for padding the
> control packets. But isn't single-hop Albert's main use-case?
It's Albert's primary use case. And, I think a common related one is
protecting tunnels of various flavors; e.g. GRE or IPsec.
> I believe we
> should add the echo option in the large-packets draft, it has the benefit
> that you get the desired functionality even if only 1 side of the WAN link
> supports echo. I realize not all implementations support echo so they
> might have to do pad control packets instead.
While I don't think Albert or I would have any objections to adding Echo
discussion in the existing document, we perhaps risk running into one of the
issues Xiao and I had briefly discussed. Echo is intentionally
under-specified in RFC 5880 et seq. While it's possible that we can simply
put in a discussion section that says "if you use Echo mode with similar
padding, you can get similar benefit", I think that may be as far as we want
to go.
The related observation is that nothing stops an Echo implementation from
doing this with no changes to the protocol. :-)
-- Jeff
