Re: [TLS] Next protocol negotiation

Nikos Mavrogiannopoulos <> Wed, 20 January 2010 15:39 UTC

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Date: Wed, 20 Jan 2010 16:39:17 +0100
From: Nikos Mavrogiannopoulos <>
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Subject: Re: [TLS] Next protocol negotiation
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Adam Langley wrote:

> <> wrote:
>> I was wondering, why not do it the other way round. I mean why not
>> upgrade to TLS from
>> websockets using the rfc2817 method (Upgrading to TLS Within
>> HTTP/1.1), or similar. Wouldn't
>> that solve the need for a new TLS extension?
> Using HTTP Upgrade is a possibility for this, as discussed:
> "We could have wrapped the first request in an HTTP presentation.
> Base64 encoding and the HTTP headers increase the size of the request.
> Later disambiguation also makes the server side code less modular. Lastly,
> it simply strikes one as the wrong thing to do; admiting defeat and
> accepting an accumulation of protocol detritus."

Ok now I see your point. However I still suggest solving issues at the
appropriate layer, even that has some performance cost. Consider the
case where applications add extensions to TCP. In the long term I
believe it pays off by having a simple security provider protocol and
simple applications that implement it. (not that today's TLS is that
simple - and there are already some application specific extensions).

best regards,