Subject: [babel] draft-boutier-babel-source-specific-02

From: Matthieu Boutier <[email-masked]>
Date: Thu, 15 Jun 2017 16:56:58 +0200

Hello,

I've submitted the 02 version.

    https://datatracker.ietf.org/doc/draft-boutier-babel-source-specific/

To be discussed:

  - choose one proposal for wildcard requests,

  - Define the Source Prefix sub-TLV type,

  - I've deprecated source-specific wildcard updates (disagreements ?),

  - should I put a note about incompatibility with RFC 6126 ?

About wildcard updates: they're used to retracts all routes, typically
before a node stops.  I don't see any use case of source-specific wildcard
updates (which would mean "retraction of source-specific routes")...

Matthieu

---

From: Toke Høiland-Jørgensen <[email-masked]>
Date: Thu, 15 Jun 2017 17:39:45 +0200

Matthieu Boutier <[email-masked]> writes:

> before a node stops. I don't see any use case of source-specific
> wildcard updates (which would mean "retraction of source-specific
> routes")...

Does this mean whatever we decide for wildcard requests applies to
wildcard updates as well?

-Toke

---

From: Juliusz Chroboczek <[email-masked]>
Date: Thu, 15 Jun 2017 17:48:30 +0200

>     https://datatracker.ietf.org/doc/draft-boutier-babel-source-specific/

Do people agree that this deserves a talk in Prague?  I'm asking now
because I need to start thinking about funding.

-- Juliusz

---

From: Juliusz Chroboczek <[email-masked]>
Date: Thu, 15 Jun 2017 17:49:19 +0200

> wildcard updates as well?

Yes, er, no, er, I have no idea.

-- Juliusz

---

From: Toke Høiland-Jørgensen <[email-masked]>
Date: Thu, 15 Jun 2017 18:02:10 +0200

> Yes, er, no, er, I have no idea.

I do always enjoy your elucidating comments... ;)

-Toke

---

From: Matthieu Boutier <[email-masked]>
Date: Fri, 16 Jun 2017 10:46:08 +0200

> wildcard updates as well?

That seems logical, but that's not what I propose.

When a node requests a full dump, it requests only the routes it
understand, not really a full dump.  Sending a full dump may include
unsolicited updates.

When a node retracts all its routes, the receiver, which has only
considered the routes it understand, will only retracts these routes.

Of course, like wildcard requests, we can say that to be really
conservative, a wildcard retraction only retracts the routes defined
in 6126bis.  I see no use case for that.

To conclude, whatever we decide for wildcard requests, I suggest we
deprecate any-specific wildcard retractions.

Matthieu

---

From: Juliusz Chroboczek <[email-masked]>
Date: Wed, 21 Jun 2017 02:18:08 +0200

> considered the routes it understand, will only retracts these routes.

You're right.  RFC 6126 defines wildcard retractions to apply to both IPv4
and IPv6 routes.  While 6126 does not deal with other address families or
routes with mandatory TLVs, the intent is clearly that a wildcard
retraction also applies to any other routes that this node may have
announced.  Think of a wildcard retraction as saying "I'm shutting down
really soon now, please route around me."

By the way -- it's not essential -- the node that's shutting down could
just as well send individual retractions for all the routes it advertised
previously.  Or it could send a Hello with a very small interval so that
it expires from the neighbour list of any peer.

I'd have no problem with deprecating wildcard retractions.  If people
don't believe that wildcard requests are useful, we might as well
deprecate AE 0.

-- Juliusz