Dear Naidu
I couldn't find the draft-kompella-tewg-bw-acct-00.txt
draft can you please
tell me where can i get
this draft ?
Thanks & regds
Ashwin
-----Original Message-----
From:
Naidu, Venkata [mailto:Venkata.Naidu@Marconi.com]
Sent: Thursday, August 16, 2001 7:12 PM
To: 'Ashwin C. Prabhu'; Naidu, Venkata; mpls@UU.NET;
mpls-ops@mplsrc.com
Subject: FW: Traffic Engineering
TLV
Ashwin:
Please look at my inline comments...
-> The priority/preemption is a task of MPLS Management
-> module. I would like to know why the 8 priority
levels
-> are provided in the OSPF Extension?
OSPF (for that matter any IGP) job is to flood
the TE
information throughout the area
(at present) for TE
purpose. The 8
priority levels for unreserved bw is
nothing to do with OSPF calculations. Just flood the info!
-> What i was thinking is this 8 priority levels is used by
-> the CSPF for the computation of the routes. If
so, why
-> is it Unreservable Bandwidth for the 8
priority levels ?
Yes! After flooding the TE information, ingress
LERs do
CSPF to prune links (which are
not met the requested
bw, priority,
preemption etc) to find the best path to egress.
-> does it mean that on a link we configure the Bandwidth
-> for different priority levels ?
-> (Like Priority 0 ->
30 % bandwidth etc )
-> Or this is ment for
some other purpose ?
It is not that simple, please look at Kompella's
paper
draft-kompella-tewg-bw-acct-00.txt
(and nested references)
-> As i found the
draft draft-katz-yeung-ospf-traffic-04
-> not
mentioning it clearly.
As I said, draft-katz-yeung-ospf-traffic-04 is
nothing to do
with configuration of
priority levels.
--Venkata Naidu
-> -----Original Message-----
->
From: Naidu, Venkata [mailto:Venkata.Naidu@Marconi.com]
-> Sent: Tuesday, August 14, 2001 7:37 PM
-> To: 'Ashwin C. Prabhu'; mpls@UU.NET;
mpls-ops@mplsrc.com
-> Subject: FW: Traffic
Engineering TLV
->
->
-> Prabhu:
->
->
Can anyone please tell me what are these 8
-> ->
priority levels and what for these
->
->
used ?
-> There are no set of semantics
for each priority level.
-> The
different levels provide an ordering that can be
-> used to determine preemption during the establishment
-> of LSPs. They can also be used by an
implementation
-> as a means of
ordering LSP computation and setup.
->
How to use these priority levels? Look at:
-> CR-LDP draft-ietf-mpls-cr-ldp-05.txt and
-> RSVP-TE
draft-ietf-mpls-rsvp-lsp-tunnel-08.txt
-> -> why
we need this.
-> The need for priority
levels is specified in
-> RFC 2702.
There is a consensus of eight protocols
-> being sufficient.
-> In Dan's terms...
-> "The priority attribute defines the relative
importance of traffic
->
trunks. If a constraint-based routing framework is used
-> with MPLS,
-> then
priorities become very important because they can be used to
-> determine the order in which path selection is
done for traffic
-> trunks at
connection establishment and under fault scenarios.
-> Priorities are also important in
implementations permitting
-> preemption because they can be used to impose a
partial
-> order on the
-> set of traffic trunks according to which
preemptive
-> policies can be
-> actualized."
->
--Venkata Naidu
->