The MPLS WG Archive

Cell Relay Retreat>MPLS WG Archive>month:2003-Mar> msg00265



[Date Prev][Date Next][Thread Prev][Thread Next]  
  [Date Index][Thread Index][Author Index][Subject Index]

Between OSPF RSVP...

  • From: Curtis Villamizar <curtis@fictitious.org>
  • Date: Mon, 17 Mar 2003 10:37:08 -0500
  • cc: "'Steve Yao '" <syao@chiaro.com>, "''curtis@fictitious.org' '" <curtis@fictitious.org>, "'mpls '" <mpls@UU.NET>


In message <561621C69F17D511A3A20050047340EC01AAF610@VCMD-NT1>, "Ferrell, Willi
am" writes:
>  
> Steve 
> 
> I ask a simple question or two. 
> 1. how detrimental could this be to our MPLS implementation and 
> 2. What should we do to mitigate the risk ?
> Will


Will,

What is "this" in your question?  If it partially filled RRO, we
determined it not occur except for certain conditions that are
entirely a matter of network design (such as interarea).  We also
concluded that even if the RRO was partially filled, the path-tear and
notify (if used) would handle tear down and initiate reroute.

Please be more specific in your question, if I haven't answered it.

Curtis



> -----Original Message-----
> From: Steve Yao
> To: 'curtis@fictitious.org'
> Cc: mpls
> Sent: 3/14/03 12:51 PM
> Subject: RE: Between OSPF RSVP... 
> 
> 
> 
> >Steve,
> >
> >In two messages prior you stated:
> >
> >> The RRO received at the HE only contains the IP addresses 
> >that map to half
> >> of the LSAs or LSPs that the LSP traversed. 
> >
> >You mentioned that only half the LSA/LSPDU were in the RRO, so the
> >question "What cases were you thinking of?" that you just asked should
> >be directed to you.
> 
> I asked the question since you mentioned earlier:
> 
> >It wasn't intended to cover all cases and does not depricate use of
> >path-tear.  You still didn't answer my question.
> 
> But it is ok if you don't want to answer the question.
> 
> >
> >Since you brought up the issue "where RRO may be too large" why don't
> >you do the math and tell us 1) how big the RRO would have to be to be
> >too large and 2) how likely you think that is of occurring.  RSVPd
> >objects can be 64KB each.  The IPv4 address subobject is 8 bytes long,
> >including type and length.  Add a label subobject (8 bytes) and fit it
> >into a reasonable MTU and you're still at hundreds of hops.  I get
> >200+ into a 4KB MTU and most networks seem to be going for 8K MTU so I
> >get "not very likely" for question 2).
> >
> >Curtis
> >
> 
> I agree that this is not very likely.
> 
> Steve
>  <<ATT77972.txt>> 
>