Re: Section 8.2

On Fri, 31 May 1996, Jeffrey Mogul wrote:

>     'HTTP/1.1 servers SHOULD maintain persistent connections and use TCPs 
>     flow control mechanisms to resolve temporary overloads, rather than 
>     terminating connections with the expectation that clients will retry. 
>     The latter technique can exacerbate network congestion.'
>     
>     On a practical note; how do I distinguish between an idle client, a dead 
>     client, and one that is avoiding network congestion? Should the standard 
>     give some guidelines?
> 
> Actually, the real question is "how do I distinguish between an idle
> client, a dead client, and one that can no longer be reached over
> the network?"  (Network congestion tends to result in slow but not
> totally failed communication.)
> 
> The answer to the real question is "you can't, so don't bother to try."
> Treat them all the same: when you get tired of waiting, give up.  Many
> servers seem to use a timeout of about 20 minutes for this.
                                            ^^^^^^^
Is this a typo?  Wouldn't 20 seconds be more appropriate?
That's what I use by default, though actually I vary it in some
circumstances.  I suspect in the future servers may have heuristics
to pick this time.

John Franks 	Dept of Math. Northwestern University
		john@math.nwu.edu

Received on Friday, 31 May 1996 13:47:19 UTC