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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: MAE West
On Mon, Jul 14, 1997 at 10:14:16AM -0700, Stephen Stuart wrote: > > Indeed. More importantly, Bill, he wasn't suggesting duplicating the > > 400Mbps aggregate, but _splitting_ it; it is, after all, _already_ 4 > > separate links. > > The underlying physical media may be four separate links, but at L2 > it's a single 400Mb/s aggregate. If it were split up into, say two > 200Mb/s aggregates: > > 1) assuming that costs favored intra-building connections, one of the > aggregates would be selected for pruning by the spanning tree > calculation. > > 2) assuming that costs favored having both aggregates in service, if > utilization on the two aggregates was 50% on (call it) A and 100% on B, > the 50% available on A would be wasted. Note that latency would go up, > because spanning tree would have pruned some intra-building link would > have been pruned in order to keep the inter-building link active. If this is true, then the Layer 2 bandwidth aggregation design is pretty weak, no? For example, (and yes, I know there's a world of difference) a MLPPP link is at (effectively) layer 2 (if not 1.5), and if one side of the link drops, the other side will carry what it can. Cheers, -- jra -- Jay R. Ashworth [email protected] Member of the Technical Staff Unsolicited Commercial Emailers Sued The Suncoast Freenet "People propose, science studies, technology Tampa Bay, Florida conforms." -- Dr. Don Norman +1 813 790 7592
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