Clarification on link ids, interface ids and interface indices in LMP...

[eepy@cix.co.uk]

Hi all,

My understanding of LMP was that the LINK_ID identifying an unnumbered TE link comes from the same numbering space as 
the INTERFACE_ID identifying a Data Link.  In other words, these are interface indices and they should be unique within a 
given node.  Given this, my belief is that it is invalid for a TE Link's local Link ID to have the same value as the local interface 
ID of a data link on the node (and that may be part of the TE Link).

This is implied by the LMP MIB (where the comments in the lmpTeLinkEntry and lmpDataLinkEntry state that each TEL and 
DBL correspond to an entry in the ifTable - and the implication is that these are different entries in the ifTable) - however 
there doesn't seem to be a definitive statement that says that the ifIndex in the lmpTeLinkEntry and lmpDataLinkEntry must 
be used as the local link_id and interface_id in the LMP protocol exchanges.

Can I confirm that the intention of the authors was that the link_id and interface_id in LMP protocol exchanges were taken 
from the if_index of the appropriate link?  In extension, can someone confirm (or otherwise) that it would be wrong to have 
a node use the same value for a (unnumbered) TE Link's link_id and one of its Data Link's interface_ids?  

Note - for context, I am mainly thinking of situations when link bundling is not being used, so the Data Link's interface_id is 
actually a port ID - I believe in the link bundling case, that the bundle draft is clear that a TE Link ID is unique and from the 
same number space as the component link IDs.

Thanks in advance,

Ed