[10802] in North American Network Operators' Group
Re: MAE West
daemon@ATHENA.MIT.EDU (Stephen Stuart)
Mon Jul 14 15:46:39 1997
To: "Jay R. Ashworth" <jra@scfn.thpl.lib.fl.us>
Cc: nanog@merit.edu
In-Reply-To: Your message of Mon, 14 Jul 97 13:40:36 -0400.
<19970714134036.36177@scfn.thpl.lib.fl.us>
Date: Mon, 14 Jul 97 11:48:31 -0700
From: Stephen Stuart <stuart@pa.dec.com>
> > 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?
You're mixing apples and oranges.
> 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.
That is what happens within an aggregate. The multi-link PPP channel
corresponds to an "aggregate" in the terminology that I am using.
The topic being discussed is not what happens within an aggregate, but
what happens when two aggregates are using. This would be akin to
having two multi-link PPP connections (each constructed out of some
number of physical links).
Stephen
