The MPLS WG Archive

[Curtis Villamizar <curtis@avici.com>]

In message <01c01130$842fc740$dbb00b81@default.leeds.ac.uk>, "Erickson Trejo-Re
yes" writes:
> 
> By overbooking you mean that, for example, if a voice source can be =
> treated as a VBR source with 64 KB peak bit rate and activity factor of =
> 0.4, then the reservation should be made to a higher value than the =
> computed effective bandwidth (and obviously higher than the average bit =
> rate of 0.4 times 64KB)?

I meant that the allowable sum of reservations could greatly exceed
the desireable sum of reservations.  The ingress would have to be
smart enough to lay out trafffic such that load was well distributed
and was far below the values where CAC would limit the sum of
reservations.

> I had thought that, if an MPLS node is due to use only certain =
> percentage of its total capacity to serve, for example, guaranteed =
> services, it would not be too harmful to make reservations (up to the =
> available percentage) only based on the sustained rate, with the only =
> possible consequence of temporary squeezing the throughput of =
> best-effort services. Comments?

Instead of limiting the guaranteed services to 30% by setting the
reservable bandwidth very low, the ingress can be configured to avoid
any links which are approaching or have over 30% guaranteed service.
Right now the only way to know that it is guaranteed service and now
BE is to give then different holding priorities but that is changing.

Curtis