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

[Acee Lindem <[e-mail]>]

Hi Adrian,

Adrian Farrel wrote:

> 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.

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.

> 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".)

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.


>  Can a TE LSA contain "orphaned" TLVs? I.e. can we have a continuation TE
>  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.

>  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?

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

>
>  The text needs to cover all of these questions.
> Cheers,
> Adrian
>