Re: [Idr] 答复: WG adoption call for draft-xu-idr-neighbor-autodiscovery

[Robert Raszuk <[e-mail]>]

Xiaohu,

First I did not deny anything.

I still believe that DCs should use following reachability protocols in the
order of preference:

1. Link state IGP (vast majority of DCs can use it *as is*)
2. MSDCs link state with flooding reduction
3. EBGP with central configuration

I can see a value of automatic bring-up for SD-WAN CPE - you buy a box,
place it anywhere in the world and it joins the local provider's underlay
and then VPNs you are authorized to join all with just a login name.

But in DC things do not work that way. In order to install a box you need
to open a ticket with exact connectivity map as otherwise it will not get
mounted. So you do know exactly where it is placed and who to peer with.
Configuration will be necessary anyway.

Note that validation if connectivity is done correctly according to your
map is very important, but clearly does not belong to BGP.

I wrote my proposal to a little bit enhance the #3 above mainly due to:

a) points made by some folks that IETF should not mandate or limit
operators on how to build his network

b) to limit damage which other similar proposals will result with.


> please list them explicitly and then we can consider how to address your
concerns.

Sure:

A) Permanently installing routes in RIB & FIB carried in BGP Hellos TLVs
which are UDP based is something never heard of. Clearly you are up to
great precedence here. There is no mention in the current draft when such
routes are removed.

B) All TLVs which are defined outside of need to bring up BGP session are
dangerous as they glue current BGP with say new innovation (ex: LSVR) Once
done here you can no longer separate the two.

C) Creation of new message instead of using existing BGP message requires
more changes then necessary. It also allows for extensible framework which
while normally is a feature here has a clear potential to be rather a bad
thing.

D) Sending BGP Hellos periodically - after session is up does not seems to
bring any value especially for p2p links. For LANs on the other hand (if
such requirement is in place) there are much better solutions other then
periodic BGP Hellos.

E) I see no reason to suggest in any form use of port 179 to such UDP
multicast messages


Thx,
R.