The MPLS WG Archive

[Shahram Davari <Shahram_Davari@pmc-sierra.com>]

George,

Thanks for clarification. Do you think that the last paragraph of what you just said:


>IP-centric approaches, are the right approach.  For instance the
> method proposed in draft-pan is to use normal IP pings to monitor a
> tunnel.  Only when the normal ping fails do you use the tunnel ping.
> This is used to differentiate between a loss of the ping (failure of
> the forward path) and loss of the reply (failure of the reverse path).
> 

captures what you said in the BOF? If so then I will replace that in the report.

Yours,
-Shahram

> -----Original Message-----
> From: George Swallow [mailto:swallow@cisco.com]
> Sent: Wednesday, December 12, 2001 2:17 PM
> To: Shahram Davari
> Cc: mpls@UU.NET; swallow@cisco.com
> Subject: Re: MPLSOAM BOF meeting draft minutes 
> 
> 
> Shahram -
> 
> I don't think the text below captures my comments:
> 
> > George Swallow - 
> > therefore sufficient.  Use Ping to see if everything is 
> fine. IF you cease to 
> > get ping replies, need to go to control plane for resolution of
> > problem.
> 
> Let me try:
> 
> In architeting MPLS the design goal was to offer IP based services.
> Along with that the ubiquity of IP was also assumed.  In IP unicast
> forwarding, bidirectionality is neither assumed nor assured.
> 
> Theses assumptions lead us to build unidirectional LSPs and to allow
> penultimate hop popping since the box at the end of an LSP is assumed
> to be able to forward IP packets and removing the label at the
> previous hop is a useful optimization.
> 
> IP-centric approaches, are the right approach.  For instance the
> method proposed in draft-pan is to use normal IP pings to monitor a
> tunnel.  Only when the normal ping fails do you use the tunnel ping.
> This is used to differentiate between a loss of the ping (failure of
> the forward path) and loss of the reply (failure of the reverse path).
> 
> ...George
> 
> 
> 
> ==================================================================
> George Swallow       Cisco Systems                  (978) 497-8143
>                      250 Apollo Drive
>                      Chelmsford, Ma 01824
>