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1© 2002, Cisco Systems, Inc. All rights reserved.
draft-nadeau-pwe3-vccv-00.txtIETF #56 San Francisco, CA USA
Thomas D. [email protected]
Monique [email protected]
George [email protected]
ftp://ftp-eng.cisco.com/tnadeau/oam/draft-nadeau-pwe3-vccv-00.txt
2© 2002, Cisco Systems, Inc. All rights reserved.
Based on MPLS OAM and Customer Requirements
• Driven by a need to provide a common means of testing PWEs using an in-band diagnostic mechanism.
• ftp://ftp-eng.cisco.com/tnadeau/oam/draft-nadeau-mpls-oam-requirements-00.txt
Soon to be draft-ietf-mpls-oam-requirements-00.txt
3© 2002, Cisco Systems, Inc. All rights reserved.
Motivation
• One transport tunnel can serve many pseudo-wires and we can verify that path with existing tools…
(e.g.: MPLS ping is sufficient to monitor the PSN tunnel for PE-PE connectivity, but not VCs inside of tunnel.)
• But…we cannot verify the PWs themselves using existing tools.
4© 2002, Cisco Systems, Inc. All rights reserved.
VCCV Key Points
• Provides extensible foundation for PW OAM CV/trace functions.
• Will work with supported transport tunnels MPLS and L2TPv3 (soon)
• Different CV types to support different PWs when appropriate
LSP Ping, IP Ping, VPLS (future)
5© 2002, Cisco Systems, Inc. All rights reserved.
VCCV Key Points (2)
• Modify PWE Encapsulation HeaderSome reserved bit for OAM indication.
Current bit in draft is already assigned; need to choose a new one.
Capability Signaled During VC setup as a bit mask of allowable VCCV types.Carry multiple TLVs as payload to allow for different types of OAM operations.
Support MPLS and L2TPv3 transportsSupport p2p and VPLS applications
Straight-forward to implement.• Reference
ftp://ftp-eng.cisco.com/tnadeau/oam/draft-nadeau-pwe3-vccv-00.txt
6© 2002, Cisco Systems, Inc. All rights reserved.
Example of OperationCV/Trace Using VCCV and LSP Ping
Attachment VC
VCCV PacketIs lostAttachment VC
NMS/mgr Triggers VCCV
NMS/mgr Triggers LSP ping trace when failure detected
7© 2002, Cisco Systems, Inc. All rights reserved.
Open Issues
• As currently defined VCCV parameter does NOT need to be identical in both directions of a circuit, so no cases where the signaling MUST be rejected
In order to support certain functions in future one might want to reject a setup (e.g. the far end did not indicate Ping, but I'm configured to do CV with Ping).
• The description of signaling is incorrect.
Needs to be single sided (downstream unsolicited).
• Need to add VCCV type for L2TPv3• Current bit in draft is already assigned; need to choose a new
one
8© 2002, Cisco Systems, Inc. All rights reserved.
Next Steps
• Refinements
Support L2TPv3 transport.
Editorial enhancements.
• Accept as a PWE3 WG document.
9© 2002, Cisco Systems, Inc. All rights reserved.
Thank You