Re: Death of the Internet - details at 11
2004-01-28 12:21:58
On 1/28/04 at 12:39 PM -0500, John C Klensin wrote:
The reality is that there is very little that we do on the Internet
today that require connection persistence when a link goes bad (or
when "using more than one IP address"). If a connection goes down,
email retries, file transfer connections are reconnected and the
file (or the balance of the file if checkpointing is in use) is
transferred again, URLs are refreshed, telnet and tunnel connections
are recreated over other paths, and so on. It might be claimed that
our applications, and our human work habits, are designed to work at
least moderately well when running over a TCP that is vunerable to
dropped physical connections.
Would it be good to have a TCP, or TCP-equivalent, that did not have
that vunerability, i.e., "could preserve a connection when using
more than one address"? Sure, if the cost was not too high on
normal operations and we could actually get it. But the goal has
proven elusive for the last 30-odd years -- at least in the absence
of running with full IP Mobility machinery all of the time, which
involves its own issues -- and, frankly, I'm not holding my breath.
I am rather ambivalent about this issue (it seems like the obvious
thing to do, but also seems quite painful to accomplish), but I do
think there is something missing in this response: "The cost" to
which you refer needs to be weighed against the cost of *not* doing
so, and that cost seems to have been mounting all along and shows no
sign of slowing down. The fact is that we have had to engineer all
sorts of application-layer solutions to this single problem and will
continue to do so for new application-layer protocols into the
future. Worse yet, some of those solutions continue to include
ridiculously high-cost solutions such as having to retransmit entire
files, and my guess is such costs (bandwidth and otherwise) will
continue in the future. I also think that the argument ignores the
possibility that if we do address the "connection persistence"
problem, we will be able to do many things at the application layer
that we have always avoided doing because of the cost of having to
engineer around it. From the view up here in the nosebleed section,
it seems like it is worth at least the attempt to get a solution.
--
Pete Resnick <http://www.qualcomm.com/~presnick/>
QUALCOMM Incorporated
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- Re: Death of the Internet - details at 11, (continued)
- RE: Death of the Internet - details at 11, Tony Hain
- RE: Death of the Internet - details at 11, John C Klensin
- Re: Death of the Internet - details at 11, Dave Crocker
- Re: Death of the Internet - details at 11, John C Klensin
- Re: Death of the Internet - details at 11,
Pete Resnick <=
- Re: Death of the Internet - details at 11, John C Klensin
- Re: Death of the Internet - details at 11, Jeffrey I. Schiller
- Re: Death of the Internet - details at 11, Randall R. Stewart (home)
- Re: Death of the Internet - details at 11, Iljitsch van Beijnum
- Re: Death of the Internet - details at 11, Randall R. Stewart (home)
- Re: Death of the Internet - details at 11, Iljitsch van Beijnum
- Re: Death of the Internet - details at 11, Randall R. Stewart (home)
- Re: Death of the Internet - details at 11, Daniel Senie
- Re: Death of the Internet - details at 11, Randall R. Stewart (home)
- Re: Death of the Internet - details at 11, Daniel Senie
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