Subject: [babel] Mandatory bits in git

From: Juliusz Chroboczek <[email-masked]>
Date: Tue, 23 May 2017 20:06:00 +0200

Hi,

I think I've managed to get my git branches in order.

A first attempt at mandatory bits is in branch master.  It's not quite
ready yet, I need to read the whole document to see if any other changes
are needed.

My previous attempt at relaxing the definition of AEs is in branch
relax-ae.  If you have a look, you'll see that it is much more messy than
mandatory bits -- one more confirmation that the people who convinced were
right, and I was just a stubborn ass.

Please check, agree, and implement ;-)

-- Juliusz

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From: David Schinazi <[email-masked]>
Date: Tue, 23 May 2017 22:56:29 -0700

Juliusz,

Mandatory bits do seem to fit very nicely into the spec.
https://github.com/jech/babel-drafts/commit/7eaf03906716a2c4af999d421123a279332eb8f3 <https://github.com/jech/babel-drafts/commit/7eaf03906716a2c4af999d421123a279332eb8f3>

I'll try to find time to add this to our implementation soon.

Thanks for writing this up!

David

> On May 23, 2017, at 11:06, Juliusz Chroboczek <[email-masked]> wrote:
> 
> Hi,
> 
> _______________________________________________
> babel mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/babel

---

From: Gabriel Kerneis <[email-masked]>
Date: Wed, 24 May 2017 10:30:38 +0200

On Wed, May 24, 2017 at 7:56 AM, David Schinazi <[email-masked]> wrote:

> https://github.com/jech/babel-drafts/commit/7eaf03906716a2c4af999d421123a2
> 79332eb8f3
>

Agreed. Nits:

   - I think you meant "most-significant bit" instead of "most-specific
   bit".
   - missing a closing ")" after "see <xref target="update"/>".
   - you changed "address family" to "address encoding", not sure if that
   was intended or not.

Gabriel

---

From: Juliusz Chroboczek <[email-masked]>
Date: Wed, 24 May 2017 13:56:53 +0200

> * you changed "address family" to "address encoding", not sure if that was
>   intended or not.

Yes, althoug I should have made a different commit for that.  The use of
per-AF compression state is a bug in RFC 6126; the state should clearly be
per-AE.

Per-AF compression state could in principle give better compression
ratios, but I don't see how that could be pulled off in practice.
However, it means that you cannot extend the AE space for a known AF -- if
you add a new AE that encodes IPv6 addresses, than all implementations
that handle IPv6 must know about it.

I don't think that's likely to be a flaw in practice, but per-AE is the
correct thing, so let's do it.  That's the only piece that remains of my
aborted attempt at making AEs more flexible -- mandatory bits seem much
simpler and cleaner to me now.  Full credit to all the people who bullied
me into listening.

-- Juliusz