Subject: draft-ietf-mpls-lsr-mib-02.txt nits

From: Adrian Farrel <[email-masked]>
Date: Mon, 20 Mar 2000 14:42:24 -0000

Just a couple of nits.
Apologies for not coming back with these sooner.  I have been 
at UNH doing interop.

1. LSPID
   
   In previous mail exchanges I asked why the LSPID Textual
   Convention needed to allow 63 bytes.  You answered that
   this was to allow space for IPv6 addresses.

   There are three points here.
   - Why would you put an address in the LSPID?  The address
     is a separate part of the cookie
   - IPv6 addresses don't need 63 bytes
   - The current protocols only allow exchange of a 2 byte
     LSPID.

2. Performance Tables Discontinuity Timestamps
   
   We discussed this at some length before, but left the issue
   when I ran out of bandwidth.
   
   I was asking for a discontinuity timer for each performance 
   table so that it is possible to understand the scope of the 
   reported values.  You responded that the discontinuity timer
   in the interfaceTable provides sufficient information.
   
   This may be the case for the mplsInterfacePerfTable but I
   don't see how this applies to mplsInSegmentPerfTable and 
   mplsOutSegmentPerfTable.  Perhaps you could explain, or
   reconsider adding these timestamps.

3. DiffServ
   
   I believe the question of storing DiffServ information was
   raised on the list recently.  Do you have plans to add such
   information to the LSR MIB?

4. mplsOutSegmentTSpecIndex

   You've fixed the InSegmentTSPecIndex to be Integer32, but you 
   also need to fix the Outsegment syntax which is currently 
   Unsigned32.
   
Hope this helps.
Regards,
Adrian
--
Adrian Farrel  mailto:[email-masked]
Network Convergence Group
Data Connection Ltd., Chester, UK
http://www.datcon.co.uk/
Tel: +44 (0) 1244 313440  Fax: +44 (0) 1244 312422

---

From: "Thomas D. Nadeau" <[email-masked]>
Date: Mon, 20 Mar 2000 09:47:06 -0500

Hi,

>    - The current protocols only allow exchange of a 2 byte

         I believe that we were looking to be flexible enough to
accommodate any possible label. All of the implementations I
know of use much shorter labels. However, we did not wish to
preclude any longer ones. The MPLS framework does not specify a
size, it just states that, "A label is a short, fixed length,
locally significant identifier which is used to identify a FEC."
Depending on what you define as "short", you could have 1 byte,
or 64 bytes, but probably closer to the lower number. We have
not heard from anyone else pro/con on the size which we had
chosen, so we left it as is.

>    reconsider adding these timestamps.

         There is such a discontinuity timer available from the
ifTable which can be used for all tables related to an
MPLS interface.

>    information to the LSR MIB?

         If you are referring to the EXP Bits discussion,
I think that we are currently of the position that they
should be left as is in the MIB.

>    also need to fix the Outsegment syntax which is currently

         Thanks. I caught this while running the MIB through
SMIC and fixing various other things. It will be corrected
in the next version.

         --Tom