[e2e] Can we revive T/TCP ?
braden at ISI.EDU
Fri Mar 24 11:11:15 PST 2006
At 07:31 PM 12/26/2005 +0100, Michael Welzl wrote:
>Here's something that I've had on my mind for quite a while now:
>I'm wondering why T/TCP ( RFC 1644 ) failed. I mean, nobody seems
>to use it. I believe someone explained this to me once (perhaps even
>on this list? but I couldn't find this in the archives...), saying that
>were security concerns with it, but I don't remember any other details.
As the designer of T/TCP, I think I can answer this. There are three
reasons, I believe.
(1) There are very few situations in which single-packet exchanges
are possible, so T/TCP is very seldom a significant performance
improvement. But it does have significant complexity.
(2) Since the server is asked to do a perhaps signficant computation
before the 3WHS has completed, it is an open invitation to
DoS attacks. (This would be OK if you could assume that all
T/TCP clients were authenticated using IPsec,)
(3) I have heard rumors that someone has found an error in the
specific state transitions, of T/TCP although I have never seen
More information about the end2end-interest