Re: [Isis-wg] draft-eastlake-isis-trill-00.txt

[Donald Eastlake <[e-mail]>]

Hi Vishwas,

On Sun, Jun 20, 2010 at 11:13 PM, Vishwas Manral <[e-mail]> wrote:
> Hi Don,
>
> I had a cursory look at the draft.
>
> I thought there was one issue you need to consider which might change the
> shape of the draft itself. Unlike all other protocols IS-IS TLV’s has a
> length field of only 8 bits which means that having sub-TLV’s which are very
> big is not preferred. Seeing the size of sub-TLV’s defined it seems we will
> as well need different TLV’s for each sub-TLV. I would think it is better to
> define them as separate TLV’s.

Thanks for your comment. I guess it would be nice for TRILL if some or
all of the proposed sub-TLVs were TLVs. But TLV types are a limited
resource.

I've done a scan of the draft. I don't see any problem with the fixed
length sub-TLVs, which are small. They should fit fine within the TLV
specified to contain them. There are also a number of variable length
sub-TLVs. But I believe that, in many cases, these variable length
sub-TLVs will be fairly short. And in cases where they are larger,
perhaps not fitting in a single enclosing TLV, the enclosing TLV can
be repeated and I don't think the two bytes of overhead per repetition
are a big deal.

So, if there is a consensus to change one or more of these sub-TLVs to
TVLs, I'd be happy to do that. Otherwise, I don't plan to make such
changes.

> Have a look at the TE related TLV’s. You will notice that SRLG is a separate
> TLV in itself (if memory serves me right). Let me go through the draft and
> give you information about the content itself.

SRLG? RFC 5305 specified three TLVs:
      Extended IS Reachability
      Traffic Engineering Router ID
      Extended IP Reachability

> Thanks,
> Vishwas

Thanks,
Donald

> ________________________________
>
> From: [e-mail] [mailto:[e-mail]] On Behalf
> Of Donald Eastlake
> Sent: Sunday, June 20, 2010 7:32 PM
> To: isis mailing list
> Subject: Re: [Isis-wg] draft-eastlake-isis-trill-00.txt
>
>
>
> A error has been pointed out on the TRILL WG mailing list:
>
> In Section 2.5, Page 17, Length is "1 + 9*n" not "2 + 9*n".
>
>
>
> Thanks,
>
> Donald
>
> On Fri, Jun 11, 2010 at 1:53 PM, Donald Eastlake <[e-mail]> wrote:
>
> Hi,
>
>
>
> I've submitted a draft proposing IS-IS support for TRILL:
>
> http://tools.ietf.org/html/draft-eastlake-isis-trill-00
>
> Thanks,
>
> Donald
>
> =============================
> Donald E. Eastlake 3rd   [phone] (cell)
> 155 Beaver Street
> Milford, MA 01757 USA
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>
>