Subject: Re: Working Group Last Call for "Traffic Engineering Extensions to OSPF version 3"

From: Adrian Farrel <[email-masked]>
Date: Mon, 23 May 2005 11:33:16 +0100

Hi, 

Two comments... 

1. Would it be possible to clarify the behavior if the scope is
  set to some value other than 01? Is it a requirement that the
  scope be ignored in that case, that TE information be allowed
  to be flooded out of the area, or that the LSA is rejected? 

  Given the setting of the U-bit, this may be hard to control
  properly and I suspect the best you can do is say MUST
  be transmitted as 01 and SHOULD only be flooded within
  the area. 

2. Section 4 - Router IPv6 Address TLV 

  "The Router IPv6 Address TLV has type 3, length 16, and a value
   containing a 16 octet local IPv6 address.  It MUST appear in exactly
   one Traffic Engineering LSA originated by an OSPFv3 router supporting
   the TE extensions." 

  I am confused by 'MUST appear in exactly one'.
  Can a router advertise multiple Router addresses? (Hint, please talk to
  the CCAMP ASON Routing design team for a very good reason why the answer
  is "yes".)
  Can a TE LSA contain "orphaned" TLVs? I.e. can we have a continuation TE
  LSA that does not carry a Router Address TLV?
  Given that a router has (probably) more than one "stable IPv6 address
  that is always reachable if there is connectivity to the OSPFv3 router"
  must all of these be advertised in Router Address TLVs? 

  The text needs to cover all of these questions. 

Cheers,
Adrian

---

From: Acee Lindem <[email-masked]>
Date: Mon, 23 May 2005 09:01:54 -0400

Hi Adrian,

>  be transmitted as 01 and SHOULD only be flooded within

I'll change the text to say the flooding scope MUST be set to 01. This
is enough since flooding outside the orginating area would not
be compliant with OSPFv3.

>  the CCAMP ASON Routing design team for a very good reason why the answer

The intent is that there is at least one stable routable address for the 
OSPF TE router.
There is a proposal to advertise multiple addresses using the TE Node 
Address TLV.

>  LSA that does not carry a Router Address TLV?

I don't understand this - each TE LSA has a unique LSID. An OSPFv3 router
can originate multiples per area.

>  must all of these be advertised in Router Address TLVs?

I think the TE node address TLV is meant to advertise additional
addresses. At one time, this TLV was to take on the function of the
Router IPv6 Address TLV. However, it was felt that have a single
preferred router address was preferable. Here is a link to the TE node
address draft:

http://www.ietf.org/internet-drafts/draft-ietf-ospf-te-node-addr-02.txt

Thanks,
Acee