Re: [TLS] HTTPS client-certificate-authentication in browsers

Henry Story <> Wed, 27 July 2011 21:56 UTC

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From: Henry Story <>
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Date: Wed, 27 Jul 2011 23:56:49 +0200
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Subject: Re: [TLS] HTTPS client-certificate-authentication in browsers
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On 27 Jul 2011, at 23:29, Martin Rex wrote:

>> They find HTTPS' way of doing that intrusive.
>> On the web you logoff from (or by) the server.
>> Naturally logoffs must trickle down to clients
>> if they have logged-in using HTTPS CCA otherwise
>> they are de-facto logged-in due to the TLS caching.
> "Logoff" is a pure server-side concept with respect to server-side
> state.  A logoff concept that requires cooperation from the client
> is technical nonsense.  Any server-side destruction of backend-state
> associated with particular clients must work completely independent
> of what the client does.  Early consensual destruction of backend
> state if the client explicitly asks for it is OK.  But any
> server-initiated "logoff" concept that involves the client
> amounts to technical cluelessness.

why is that? Why can't the client log itself off. That would be much better
for the user, as he would be in control of his identity.

This could be done easily by a browser both with cookies and with TLS:
 - with cookies: the browser should tie every cookie and state to a user identity. When the
    user switches identity, the cookies stop getting sent. For the server that ends up being
    the equivalent of a log-off.
 - with TLS the client breaks the connection, and re-established a completely new one.


Social Web Architect