Re: FW: path TLV & srlg TLV

[Yakov Rekhter <yakov@juniper.net>]

Jun,

> No. I don't think so. 
> 
> But what I want to point out is,
> 
> (1). There is inconsistency between "LSP Hierarchy with Generalized MPLS TE"
> and 
> "Generalized Multi-Protocol Label Switching (GMPLS) Architecture" on this
> matter 
> (whether to use path TLV or SRLG TLV in FA advertisement).

that certainly has to be fixed (in the next iteration of the
Architecture document).

> (2). If we only advertise Path Information for the FA, then the SRLG
> information of the FA 
> can be derived, just as you specified in the "LSP Hierarchy" draft, it is
> "the union of the 
> SRLGs of the underlying TE links that make up the FA-LSP path".
> 
> On the other hand, if we only advertise SRLG Information for the FA, then
> the FA-LSP's path 
> information becomes opaque to all the LSRs other than the headend LSR. This
> makes it difficult 
> for the LSR to make a routing decision with "Link", or "Node" diversity
> requirement.

while L in SRLG stands for "links", one could be quite creative
with the usage of SRLGs, and use them not just for links, but for
nodes as well. Doing this would allow to support both link and node 
diversity.

Yakov.

> 
> Thanks.
> 
> -Jun
> 
> > -----Original Message-----
> > From: Kireeti Kompella [mailto:kireeti@juniper.net]
> > Sent: Friday, March 15, 2002 5:05 PM
> > To: Jun Yu
> > Cc: 'ccamp@ops.ietf.org'
> > Subject: Re: FW: path TLV & srlg TLV
> > 
> > 
> > 
> > 
> > On Fri, 15 Mar 2002, Jun Yu wrote:
> > 
> > > > Section 4.1.10, the context is changed to "SRLG 
> > Information" from the
> > > > previous "Path Information".
> > 
> > Do you think it is useful to include both SRLG and Path information?
> > 
> > Kireeti.
> > 
>