Re: Progressing BC Models was RE: Progressing MAR

On Fri, Mar 14, 2003 at 03:56:30PM -0600, Ash, Gerald R (Jerry), ALABS wrote:
> > Incidentally, perhaps mechanisms like
> > draft-meyer-mpls-soft-preemption-00.txt may also alleviate some of the
> > concerns associated with preemption.
> 
> If you mean that SPs who don't use preemption will suddenly opt to use soft preemption, certainly not.  Also, if one does too much soft preemption, and forces a lot of flows off of short routes onto much longer, inefficient routes, this would (perhaps severely) degrade network performance.  There are studies which show that effect.  One of the applications of bandwidth reservation mechanisms (as in MAR), used in large-scale networks today, is to protect against such an effect.

I am not sure how soft preemption, referring to the recent draft, forces
flows off short routes onto longer ones.  Are you referring to preemption
itself, regardless of whether its hard or soft?

-dave

> 
> Thanks,
> Jerry
> 
> 

-- 
Dave Cooper
IP Engineering, Global Crossing Ltd.
(602) 744-3473