The MPLS WG Archive

[abhay <abhay@multitech.co.in>]

Tom,

    Thanks for the assurance...

    Reminds me of after sales service....LOL,;)

    Regards,

    Abhay

"Thomas D. Nadeau" wrote:

         Hi,

>     This new explanation would have helped me sometime ago,
>     It did take a while for me to get  what you were saying then.
>     Better late than never..8)

         Glad to have helped. In the future, please speak up if
something is unclear, since if it is unclear to you, there
are probably lots of others that it is unclear to as well. 8)

         --Tom

>     Thanks
>
>     Regards,
>
>     Abhay
>
>
>"Thomas D. Nadeau" wrote:
>> >In section 7 of draft-ietf-mpls-te-mib-06.txt the interface
>> >stack is shown as:
>> >
>> >         +------------------------------------------------+
>> >         | MPLS-Tunnel-interface ifType = mplsTunnel(150) |
>> >         +------------------------------------------------+
>> >         |        MPLS-interface ifType = mpls(166)       |
>> >         +------------------------------------------------+
>> >         |               Underlying Layer                 |
>> >         +------------------------------------------------+
>> >
>> >It is not clear to me how the particular lower layer of the tunnel
>> >interface is chosen.
>> >
>> >In the case of a tunnel interface created but not yet signalled, I
>> >imagine it would be layered over nothing (ifindex 0).
>> >
>> >Once signalled, would it be the mplsOutSegmentIfIndex of the
>> >tunnel's underlying cross connect?
>> >
>> >If so, I assume a rerouted tunnel, since it might have a different egress
>> >interface, might need to be restacked onto a different interface.
>> >
>> >Should a tunnel also be layered over the mplsInSegmentIfIndex (if
>> >nonzero)?
>>
>>          Sorry for the confusion. The text in the draft needs
>>a few sentences to clarify. Something like this:
>>
>>          In the case where the tunnel interface is
>>present at the head-end of the tunnel, the
>>tunnel interface should be stacked upon the
>>outgoing MPLS interface.  In the case where
>>the tunnel interface is optionally represented
>>at the egress of the tunnel as well, it
>>should be stacked upon the incoming MPLS
>>interface. If the tunnel interface has been created,
>>but no LSP has been signaled for the tunnel,
>>the tunnel should not be stacked upon any underlying
>>interface. If the tunnel's underlying LSP is
>>changed, then the interface stacking should be
>>changed accordingly to the new MPLS interface
>>as described above.
>>
>>          --Tom