On Wed, 4 Feb 1998, Dave Siegel wrote:
Extremely weak metaphore, since a source quench indicates there weren't enough buffers available to send your packets.
Now, if the freeway was full, and cars started dropping out of the space/time continuum, that'd be more like a source quench. ;-) The freeway would call your wife at home and say "sorry, but your husband didn't make it to work because the freeways were too full." If wife runs correct a correct TCP implementation, she would know to initiate "slow start" and would send out her husbands at a slower rate until she gets a feel for how bad the traffic is.
ROFL, nice extension. But this is not true because, as you say below, gateways don't source quench anyore.
One then wonders how well Win95 implements source quench, if at all.
Which side of the implementation do you mean? as a client, or as a gateway? I suppose it doesn't really matter. Since source quenches are not supposed to be used on routers anymore, the expectation of receiving a source quench on a large network (like the Internet) is a bad one, so the TCP implementations have to implement congestion controls through other means anyhow.
As a client, of course, since end-to-end source quench is the only alternative available. And consider the near future scenario where a user with a cable-modem connected via Ethernet to their nice new NC (with cheapest bus design possible to contain costs) has requested a URL from a <insert whomping fast server here> connected via OC-3 to the Internet. It seems likely a source quench will come in handy to provide flow control.
TCP/IP Illus. Vol. I by W. Richard Stevens has a pretty good explanation of what source quenches are.
Don't have Mr. Stevens handy, but from RFC777 (1981!), when both types of source quench were defined: ...A destination host may also send a source quench message if datagrams arrive too fast to be processed. The source quench message is a request to the host to cut back the rate at which it is sending traffic to the internet destination. This is what I was getting at. Flow control versus congestion control. ------------------------------------------------------------------- Scott Whyte 408.527.5713 |Any opinions expressed herein are Network Supported Accounts (NSA) |mine and not cisco's... CCIE 3340 | | "Eschew Obfuscation"