[Babel-users] [babel] source sub-tlv

[Juliusz Chroboczek]

Matthieu, could you please write up a new version of the I-D with your
encoding?  You might want to speak to Gwendoline, since she needs to write
up her TOS-specific encoding.

> If we keep this behaviour and mix tos-specific routes, we will have
> to send 4 wildcard requests to have all routes.  I see two reasonable
> options:

>   - only keep (legacy) wildcard requests, and reply with a full dump.

That's reasonable, although slightly confusing.  (Call that (1).)

>   - send one request with all sub-TLVs you know but without mandatory
>     bit, and reply to all options you know about.

That's not -- it would require allocating a full new set of sub-TLVs.
Plus I find this confusing.  (Call that (2).)

There are two other possibilities:

  3. Send a non-specific wildcard request for non-specific routes,
     a source-specific wildcard request for source-specific routes, etc.

  4. Deprecate wildcard requests -- say that they MAY be replied to, but
     SHOULD NOT be sent by new implementations.

Now wildcard requests are fairly rare -- they are only used to speed up
convergence at boot time, as well as by debugging tools (although we have
no such debugging tools yet -- all debugging tools known to me connect to
the local socket of a node).  So sending four TLVs in a single unicast
packet instead of a single TLV is not prohibitive, and is much simpler
than the alternatives.

I support (3).  Last time I spoke to him, Toke supported (4).  I am
opposed to (2).  I can live with (1).

-- Juliusz