Hi Kireeti,

Though I agree the approach you suggest does minimize the amount of effort
for the working group to get similar functionality in OSPFv3 as OSPFv2, by
simply ignoring the OSPFv2 header(i.e. first 20 bytes of the payload).

I prefer a cleaner approach from the protocol implementations point of view.
Probably giving an LSA type to Area Scope TE LSA's and using the Link ID as
instance id. I guess Spencer had tried a similar approach in the draft
http://www.watersprings.org/links/mlr/id/draft-giacalone-te-optical-next-02.
txt .

Thanks,
Vishwas

-----Original Message-----
From: Kireeti Kompella [mailto:kireetiJUNIPER.NET]
Sent: Tuesday, October 08, 2002 1:01 PM
To: OSPFDISCUSS.MICROSOFT.COM
Subject: Re: OSPFv2 Opaque LSAs in OSPFv3

> If you take into account changes to the LS type for OSPFv3, the code
points
> are compatible. For OSPFv3, the LS Type is 16 bits (versus 8 for OSPFv2)
and it
> contains the flooding scope and a bit indicating what to do with
unrecognized
> types.

No kidding!

> There are no LS type collisions pervent use of the same function codes.

I beg to differ.

> OSPFv2 OSPFv3
> Link Scoped Opaque LSAs 0x09 0x0009
>
> Area Scoped Opaque LSAs 0x0a 0x200a
>
> AS Scoped Opaque LSAs 0x0b 0x400b

Where did you read this? I see in rfc 2740:

         LSA function code LS Type Description
         ----------------------------------------------------
         1 0x2001 Router-LSA
         2 0x2002 Network-LSA
         3 0x2003 Inter-Area-Prefix-LSA
         4 0x2004 Inter-Area-Router-LSA
         5 0x4005 AS-External-LSA
         6 0x2006 Group-membership-LSA
         7 0x2007 Type-7-LSA
         8 0x0008 Link-LSA
         9 0x2009 Intra-Area-Prefix-LSA

which says that function code 9 represents Intra-Area Prefix LSAs;
it doesn't define a function code 10 or 11.

Since Function Codes are independent of flooding scope in v3, the
LS types 0009, 4009 and 6009 should be interpreted as link local,
AS-wide and ?? Intra-Area-Prefix LSAs, i.e., mostly nonsense. The
same applies to 0001, 4001 and 6001, etc.

Using the value 0009 for Link Local Opaque LSAs (i.e., requiring that
the function code be interpreted *in the context of the flooding scope*)
negates the entire point of separating LS function and flooding scope.

Kireeti.

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