Re: [keyassure] publishing the public key

Stephen Kent <kent@bbn.com> Tue, 22 February 2011 02:46 UTC

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Date: Mon, 21 Feb 2011 21:00:14 -0500
To: Henry Story <henry.story@bblfish.net>
From: Stephen Kent <kent@bbn.com>
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Cc: WebID Incubator Group WG <public-xg-webid@w3.org>, keyassure@ietf.org
Subject: Re: [keyassure] publishing the public key
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At 12:49 AM +0100 2/22/11, Henry Story wrote:
>...
>  >
>>  Do you mean "identifies" or "authenticates?" I think most folks 
>>view the DNS name (or URL) as the identity of the web site.
>
>Partly. The DNS domain name is a name that one could think of as 
>referring to a set of services, each of those having a name of the 
>form name:port. The relation between the service name and the public 
>key forms an identifying description, or I should say  a definite 
>description  as it is known in philosophy. I used the following 
>example:
>
>   name:port knowsPrivateKeyof pubK

I don't think that most users, who often can't even tell if they have 
contacted a TLS-secured site, would think of a public key as part of 
the identity for the service. I also don't think that most of them 
think about the port either.

>That sentence does not authenticate, it describes. But it is part of 
>the TLS authentication protocol. Authentication is the process that 
>uses that information to prove the authorship of the messages sent 
>down a socket.

once the TLS session has been established, it is symmetric crypto, using a key
delivered or derived using a public key (or pair thereof) that provides the
data origin authentication and connection-oriented integrity guarantees to
which you allude.

>  > We're debating the mechanics of how to enable a client to verify 
>that the asserted identity matches the client's expectations, based 
>on the content of a series of DNS records.
>
>Yes, that is what the next part of my e-mail was describing the 
>logic of. Now in the case of server identity the client knows what 
>it wants the server's identity to be, since it initiated the call, 
>went to DNS, found the ip address, and connected. The clienet can 
>then use the public key found in DNS (or returned  by the server) to 
>authenticate the service it is connected to.

right.

Steve