Re: Our ALPN protocol IDs

is there no version transmitted anywhere (outside of ALPN).... or are we 
going to rely on ALPN to communicate that?

I'll have a big problem if we're talking about framing everything in TLS 
just so we can use ALPN.

Normal protocol design mandates having a version field somewhere in some 
message.  I've never found in practise this to be unnecessary, and any 
custom protocol I've ever worked with where someone omitted a version 
stamp, has been a nightmare when it comes to making changes.

So if we've truly dropped all version fields from the protocol I would 
strongly urge revisiting that decision.

------ Original Message ------
From: "Martin Thomson" <>
To: "Adrien de Croy" <>
Cc: "Carsten Bormann" <>; "Mark Nottingham" <>; 
"HTTP Working Group" <>
Sent: 6/12/2013 11:43:04 a.m.
Subject: Re: Our ALPN protocol IDs
>On 5 December 2013 13:20, Adrien de Croy <> wrote:
>>  by current definitions of what constitutes minor vs major version 
>>  2.1 would be compatible with 2.2. If it isn't you'll call it 3.0.
>We lost strong ties to that convention when we dumped the version
>field from the protocol. We can, if we like, choose new conventions
>for 2 and onward.

Received on Thursday, 5 December 2013 23:31:37 UTC