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 jra@baylink.com 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