Subject: Query regarding draft-ietf-ospf-te-node-addr

From: Nic Neate <[email-masked]>
Date: Fri, 15 Oct 2004 17:05:52 +0100

Hi,

We're implementing the Node Attribute TLV defined in
draft-ietf-ospf-te-node-addr-01 as part of OSPFv3-TE
(draft-ietf-ospf-ospfv3-traffic-02).

I have a query regarding the use of the Node Attribute TLV which I was
hoping you would resolve.  In draft-ietf-ospf-te-node-addr, it's not clear
whether a router is allowed to originate more than one Node Attribute TLV
(where each TLV is of course in a different Intra-area-TE-LSA as per RFC3630
section 2.4).  Could you please clarify this for us.

We believe that it should be allowed (similar to the way a router may
originate multiple link TLVs) in order to provide space for a large number
of IPv6 addresses.

Section A.1 of RFC 2740 states the following.

                     ...IPv6 fragmentation should be avoided whenever
   possible.  Using this reasoning, an attempt should be made to limit
   the sizes of OSPF packets sent over virtual links to 1280 bytes...

A 1280 byte Link State Update packet only allows for 77 IPv6 addresses in an
Intra-area-TE-LSA containing a Node Attribute TLV.  We want to provide the
flexibility to include more than that, which means we need to allow a router
to originate multiple Node Attribute TLVs.

Many thanks,

Nic