Re: [Mpls-interop] MPLS-TP OAM requirements - AIS/LockNotif - Can MIPs send "usolicited" OAM messages ?

[Martin Vigoureux <[e-mail]>]

Huub,

please see in-line.
regards,
-m

Huub van Helvoort a écrit :
> Bonsoir Martin,
> 
> You wrote:
> 
>> as part of the discussion on AIS/Lock Notification,
>> the server layer MEPs, detecting a fault/lock condition, should
>> inform (the MEPs of) the client layers relying on that
>> server layer and which are affected by the condition.
>>
>> However as I understand it is not the MEP (sMEP) of the
>> server layer that sends a notification to the client layers
>> MEPs (cMEP) but the MIP (cMIP) of the client layer which
>> is hosted on the same node than the MEP (sMEP).
>> See the figure below (where the double dashed line is
>> an LSP, and the ~ line represents an LSP nested in the
>> other LSP.
>>
>> +------+      +------+      +------+      +------+
>> |      |------|      |------| cMIP |~~~~~~| cMEP |
>> |      |      |      |      |  ^   |      |      |
>> |      |      |      |      |  |   |      |      |
>> |      |      |      |      |  |   |      |      |
>> |      |======|      |======| sMEP |      |      |
>> +------+      +------+      +------+      +------+
> 
> I modified the figure to align with what you wrote.

[mvx] thx. In fact the double dashed line was already there
       but with quite some spacing between the top and bottom.
> 
>> Therefore can MIPs send OAM messages without having priorly received one
>> or did I miss something?
> 
> No, a MIP can only respond to messages it receives from a MEP
> that has the same MEG level, i.e. exists in the same path.
> 
> In your figure the cMIP ignores messages sent by sMEP.

but then, how does a Lock condition of the lower LSP
is notified to cMEP?

> 
> Cheers, Huub.
>