Subject: [PWE3] comments on draft-ietf-pwe3-mpls-eth-oam-iwk-00

From: "Newton, Jonathan" <[email-masked]>
Date: Fri, 29 May 2009 17:06:55 +0100

Hi folks,
 
Some comments on draft-ietf-pwe3-mpls-eth-oam-iwk-00
 
1.2: As there a number of other failure modes that could apply, perhaps
'Failure to receive CCMs' could be reworded to 'CC failure'
 
3.1: The statement about AIS does not seem to make sense in the context
CFM AIS - we talk about a 'local MEP notifying a remote MEP of a fault
using AIS' - this is not possible under CFM as a MEP would send AIS in a
direction opposite to its peer MEP.
 
3.1:  I am not sure about the use of active CCM suspension to indicate a
PE fault - surely it would make more sense here to use an indication
such as is available in the port or interface status TLVs?
 
4.1:  Not sure the benefit of putting specific information about what
constitutes a CCM fault - suggest removing this and replacing with "CC
failure".
 
5.1/5.2: As above, I am not sure that the AIS statement makes sense - we
cannot send AIS outwards on the AC for a down MEP on the AC (or up MEP
on the emulated LAN interface).  AIS towards the AC would have to be
generated by an UP MEP on the AC or a down MEP on the emulated LAN
interface.  
 
5.1: For the interface status TLV, we should also state that an
immediate CCM should be transmitted.  Also, I am not sure that it is
really envisaged that there should be configuration that enables and
disables the interface status TLV - is this more a question of support
rather than configuration?  
 
5.1/5.2/5.3/5.4:  For E-LMI notification - in the event that this is a
VPLS and only one of the PW has failed, we should send a
'partially-active' message?
 
Some information on VLAN imposition would be useful, to clarify where
the OAM should be applied for RAW mode vs tagged mode PW and (non)
service-delimiting tags
 
Cheers,
~Jon.

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