[Babel-users] Source-sensitive packet's format

[Juliusz Chroboczek]

> switching to a new TLV number for the newer flag-less format and sending
> warnings for receipt of the old ("old style babels packet received,
> please update babel on that machine") seems most comforting to me.

I feel your pain, Dave, but that's something that I have to take a firm
stand about, or else we'll never get anything done.  Until a TLV is frozen,
it's not frozen.

> (I'm allergic to the number 13, anyway)

That's when Babel gets its Barmitzvah.

> I would not mind a shim of some sort protecting against older babels's
> format and newer...

The packet parser is fairly robust, so you'll see some routes missing, but
assuming enough route diversity Babel should route around the damage.  And
it will encourage you to do something about all the obsolete versions of
babeld you're running[1].

We could in principle keep the Flags field and simply rename it to Reserved.
That's one octet lost per source-specific update, until the end of eternity.
Opinions?

-- Juliusz

[1] I'm picturing an area of Californian shrubland, yellow grass between
    the dried up bushes, lizards, scorpions, vultures, the odd triceratops
    here and there.  In the background, a rusting 1985 Cadillac, on bricks.
    Dave, rubbing his chin and staring thoughtfully at the 2600, is
    wondering why it won't take his latest OpenWRT image.  Fade out as
    a black helicopter hovers on the horizon.