RE: Progressing BC Models was RE: Progressing MAR

["Ash, Gerald R (Jerry), ALABS" <gash@att.com>]

>> 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?

The draft says: 
"a new preemption pending flag helps more gracefully mitigate the re-route process of displaced LSPs."

It's the re-routing of preempted LSPs (onto longer paths) that I'm referring to.

Jerry