nanog mailing list archives
Re: UUNET Routing issues
From: "Petri Helenius" <pete () he iki fi>
Date: Fri, 4 Oct 2002 01:19:54 +0300
At 155 Mbps you need 32 MB worth of buffer space to arrive at a delay like this. I wouldn't put it past ATM vendors to think of this kind of over-enthusiastic buffering as a feature rather than a bug.
Vendor C sells packet memory up to 256M each way for a line card. Whether this makes any sense depends obviously on your interfaces. Theoretically it makes sense to be able to accommodate the number of flows you´re carrying times the window size advertised by TCP. In live networks not too large a percentage of the flows send data at maximum so one would expect to have a few thousand "full" flows on a link at time. 64k window for thousand flows would use 64M buffer memory. (not counting memory utilization inefficiencies) If you go deeper into the equation and start to analyze how fast you´ll get the packets in anyway, the associated mathematics will require a significantly longer presentation which you´ll probably find easily by Google. Pete
Current thread:
- Re: UUNET Routing issues, (continued)
- Re: UUNET Routing issues Patrick_McAllister (Oct 03)
- Re: UUNET Routing issues Eric Whitehill (Oct 03)
- RE: UUNET Routing issues Brennan_Murphy (Oct 03)
- Re: UUNET Routing issues sigma (Oct 03)
- Re: UUNET Routing issues Chris Adams (Oct 03)
- Re: UUNET Routing issues Matt Levine (Oct 03)
- Re: UUNET Routing issues Vinny Abello (Oct 03)
- Re: UUNET Routing issues Marshall Eubanks (Oct 03)
- Re: UUNET Routing issues Jared Mauch (Oct 03)
- Re: UUNET Routing issues Iljitsch van Beijnum (Oct 03)
- Re: UUNET Routing issues Petri Helenius (Oct 03)
- Re: UUNET Routing issues Iljitsch van Beijnum (Oct 04)
- UUNET is not the Internet (and neither is AOL) Sean Donelan (Oct 04)
- Re: UUNET is not the Internet (and neither is AOL) Tim Thorne (Oct 05)
- Re: UUNET is not the Internet (and neither is AOL) Sean Donelan (Oct 05)
- Message not available
- Re: UUNET is not the Internet (and neither is AOL) Vicky O. Mair (Oct 06)
- Re: UUNET is not the Internet (and neither is AOL) alex (Oct 07)
- Re: UUNET is not the Internet (and neither is AOL) Sean Donelan (Oct 07)
- RE: UUNET is not the Internet (and neither is AOL) Cleve Mickles (Oct 07)
- Re: UUNET is not the Internet (and neither is AOL) Jared Mauch (Oct 07)
- RE: UUNET is not the Internet (and neither is AOL) Ryan Fox (Oct 07)
- Re: UUNET Routing issues sigma (Oct 03)
- Re: UUNET Routing issues Patrick_McAllister (Oct 03)