nanog mailing list archives
Re: exchange point media (was: Re: MAE-EAST Moving? ...)
From: Wayne Bouchard <web () typo org>
Date: Wed, 14 Jun 2000 23:11:00 -0700 (MST)
On Wed, 14 Jun 2000, Brandon Ross wrote:While there are certainly shortcomings to using GbE as a public exchange infrastructure, I fail to see how a 1500 byte MTU has anything to do with it. In every network I have ever seen, there have very, very rarely been any packets larger than 1500 bytes.One of the major arguments against gigE I've heard is the lower MTU. Yes, currently there are not much packets that are larger than 1500 due to endsystems, but if we limit the infrastructure then there'll never be a larger MTU here. ATM/FDDI/POS and even Token Ring (to mix apples with oranges) all support larger MTUs and future standards will probably will as well. Therefore I believe that any shared medium used for exchanging traffic should also have the same capabilities. Larger packets mean fewer forwarding/routing decisions per second for the same megabit rate of traffic.
This was one of my concerns when GE was released. It is likely that many desktop users will be connected by fastethernet now and probably ge later on. Many web servers are already connected by ge. So there are instances where there COULD have been a continous path at 4k but instead, there is 1.5. My motiviation in wanting a higher MTU is in efficiency. One of the concerns that customers were bringing to me on occassion was not necessarily bandwidth OR latency, but rather, the composit.. data per unit of latency. They wanted to get be able to send larger amounts of data without having it fragmented. (particularly important in the multiplayer real-time gaiming bit.) As a side effect (albeit, neglibible), if there were retransmissions of a packet, there might be 1 instead of 3 with the current 1500 mtu. Some gain there as well. (Of course, given that the average packet size on the net today is less than 75K, the relative benifit of increasing the size breaks off quickly.) The utility of a higher MTU is still dubious in the practicle realm, but I agree that I would like to see the infrastructure move to 4 or 9k. ---------------------------------------------------------------------- Wayne Bouchard [Immagine Your ] web () typo org [Company Name Here] Network Engineer http://www.typo.org/~web/resume.html ----------------------------------------------------------------------
Current thread:
- Re: exchange point media (was: Re: MAE-EAST Moving? ...), (continued)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Alex Bligh (Jun 15)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Randy Bush (Jun 15)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Alex Bligh (Jun 15)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Brandon Ross (Jun 14)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Bora Akyol (Jun 14)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Jeff Haas (Jun 15)
- Message not available
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- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Jeff Haas (Jun 22)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Alex Bligh (Jun 22)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) John Hall (Jun 22)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Mikael Abrahamsson (Jun 14)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Wayne Bouchard (Jun 14)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) John Fraizer (Jun 15)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Simon Lockhart (Jun 15)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) John Fraizer (Jun 15)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Neil J. McRae (Jun 15)
- Re: exchange point media (was: Re: MAE-EAST Moving? ...) Mikael Abrahamsson (Jun 15)
- Re: MAE-EAST Moving? from Tysons corner to reston VA. Mark Tripod (Jun 16)
- Re: MAE-EAST Moving? from Tysons corner to reston VA. Alex (Jun 16)