From: ccamp-bounces at ietf.org [mailto:ccamp-bounces at ietf.org] On Behalf Of Attila Takacs
Sent: Monday, October 26, 2009 3:18 PM
To: choudarypally.subramanyam at wipro.com
Cc: ccamp at ietf.org
Subject: Re: [CCAMP] draft-ietf-ccamp-gmpls-ethernet-pbb-te-03.txt-regardingISID error handlingHi Choudarypally,Please see inline.Thanks and best regards,Attila
From: ccamp-bounces at ietf.org [mailto:ccamp-bounces at ietf.org] On Behalf Of choudarypally.subramanyam at wipro.com
Sent: Thursday, October 22, 2009 1:51 AM
To: ccamp at ietf.org
Subject: [CCAMP] draft-ietf-ccamp-gmpls-ethernet-pbb-te-03.txt- regardingISID error handlingHi ,
I am currently working on draft “draft-ietf-ccamp-gmpls-ethernet-pbb-te-03.txt” and I write this email to seek some help from experts. I have two questions regarding the Section 3 paragraph 6.
1) It say “An IB-BEB receiving a PATH message specifying one
of its CNPs can locally determine which CBPs have internal
connectivity to the I-component supporting the given CNP.”How does the CSPF function select egress CNP, based on what criteria?
The CNP is the port to which clients of the PBB-TE domain are connected to. CSPF should consider which clients the Eth-LSP is meant to support.
The
Customer network port(s) CNP are the ones that are associated with
the Customer Backbone Port PBB-TE MAC address. We are really only
signaling A TE service instance. A TE service instance is supported by two
point-to-point
ESPs where the ESPs' endpoints have the same CBP MAC
addresses.
2) Further it says “On the other hand, if there is information on
the service (I-SID) that the given ESP will support, then the IB-BEB
MUST first determine which PIP and CBP is configured with the I-SID
and MUST assign that CBP to the ESP”a) What should be action taken if ISID received in PATH message is not configured? Do I need to send PATH ERR message?
Then the ISID should be "dynamically" configured to an appropriate CBP that is connected to the CNP.
At one point we were
considering signaling I-SID information. However I believe we removed that from
the document. I-SIDs should be configured locally and should be
consistent but the signaling does not carry this information. It is purely
up to the local implementation to use I-SIDs. So multiple I-SIDs could go
to several CNPs (one or more each).
b) Assuming that I have received
more than one ISID and each one belong to different CBP port, in such case what
should be the behavior?
This should not happen provided the path computation and the service (ISID) allocation is done properly.
In case it would happen, one can try to reconfigure the CBP ISID allocations on the egress, if this is not possible then an error should be raised and sent in Path_Err. I couldn't find a good error value for this on the registry, if we want to account for this case explicitly we possibly need a new error value Routing Problem / Invalid Service ID
Since we don't signal I-SIDs I'm having a hard time parsing this scenario.
Don
I am doing the manual configuration and association of ISID to CBP.
Regards
Choudarypally