Subject: RE: draft-pan-lsp-ping-00.txt

From: Shahram Davari <[email-masked]>
Date: Tue, 10 Jul 2001 07:14:59 -0700

Hi,

> -----Original Message-----
> From: Yangguang Xu [mailto:[email-masked]]
> Sent: Monday, July 09, 2001 7:39 PM
> To: Shahram Davari
> Cc: [email-masked]'
> Subject: Re: draft-pan-lsp-ping-00.txt
> 
> 
> Hello,
> 
> It's good question. One possible solution is that the 
> penultimate hop should
> make sure the LSP ping is from its IP fast data path (there 
> seems to be some
> extra work here) and the egress LSR control plane should make 
> sure the LSP ping
> is from its penultimate hop directly. Right?

This is not possible, becasue penultimate hop MUST not look at the
IP header. 

-Shahram

> 
> Yangguang   
> 
> Shahram Davari wrote:
> > 
> > Hi,
> > 
> > An observations/question:
> > 
> > The draft says that the LSP ping packets are sent to the 
> egress LSR with UDP encapsulation. I assume the IP address of 
> the Ping packets are set to the IP address of the desired 
> egress LSR. What happens if a ping packet is delivered to an 
> undesired egress LSR? From the MPLS architecture point of 
> view, it seems that the undesired egress LSR will probably 
> try to forward the Ping packet to the desired LSR using the 
> IP address in the Ping packet, which eventually could send 
> echo-reply back to source. Therefore although the LSP has a 
> wrong path the source will never find out.
> > 
> > Yours,
> > Shahram Davari
> > 
> >  <<Shahram Davari.vcf>>
>