Re: Re: draft-suping-bfd-mpls-fecmismatch-00 questions

[David Ward <[e-mail]>]

Unfort., what you write is 180 degrees opposite from the charter of the BFD
WG and the philosophy of how the protocol is to function. BFD is not to check
the consistency of the forwarding and control plane. We do not want to 
take this protocol into the realm of control plane failure detection system
(as there are many better protocols or protocol machinery for that) but,  focus
on forwarding failure detection that can send alarms, event notification, diags,
etc up the stack.


-DWard



On Sat, Feb 26, 2005 at 09:41:49AM +0800, zhaisuping wrote:
> Hi, all
> The purpose of FEC filter in BFD is to detect the consistence of 
> the control plane and data plane. So that in the MPLS network, just
> running the BFD session(LSP-Ping is not needed) is enough for the
> defect detection. Or else such tools as LSP-Ping is needed because
> the BFD session can't detect the inconsistence of the control plane
> and data plane. 
> In the section 2 of the draft, there is description of the 
> problem the draft want to solve.
> >> Wouldn't LSP-Ping (or VCCV) be a more appropriate place to do this
> >> filter verification?
> 
> 
> >
> >LSP-Ping does a verification on the FEC itself, so a filter would add
> >nothing.
> >
> >VCCV is not a protocol.  Just a little sideband for sending IP packets
> >down a pseudowire so that you can run LSP-Ping, BFD, etc. between the
> >two ends.
> >
> >....George
> >
> >========================================================================
> >George Swallow             Cisco Systems                  [phone]
> >                           1414 Massachusetts Avenue
> >                           Boxborough, MA 01719