From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: To: 9fans@cse.psu.edu Subject: Re: [9fans] an idea From: Charles Forsyth In-Reply-To: <323e1127492657ee8f9f34692a52c7fa@vitanuova.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Mon, 26 Apr 2004 19:55:39 +0100 Topicbox-Message-UUID: 6edafdba-eacd-11e9-9e20-41e7f4b1d025 >>it's crucial that you can do the authentication, as it allows a >>service to multiplex several different users onto the same connection. >>as charles likes to point out, the "important" authentication is the >>kind that Styx uses - i.e. end to end. however, once you've >>connected to a party you trust (to some extent) to act on your behalf, >>it's still useful to be able to authenticate yourself to third parties >>through them. i say that because the end to end one is the only one that gives you reliable data. there's not much point doing the others, from the third party server's point of view. if you authenticate to a server, and use that to connect to another server, that server must trust the first server to speak for every user it sees on the connection, and it must know that. that's because the multiplexing system is in a position to manipulate fids on the connection, including the attach fids carefully associated with an `authenticated' user by an afid. having made the association, how does it really know who uses which? I am he as you are he as you are me and we are all together. it doesn't even require a modified kernel, just control of the messages on the connection. thus the multiplexing might as well be just as in Styx: different user names [whatever that might mean in a larger context] label the Tattach messages on the connection.