The MPLS WG Archive[Date Prev][Date Next][Thread Prev][Thread Next] [Date Index][Thread Index][Author Index][Subject Index] Between OSPF RSVP...
Steve Thanx, I tend to look at matters from a pesimistic perspective at times. My questions are rarely about the operational likelihood and randomly accidental factors(unless mis-configuration comes into view) but often I focus on the malicious and intentional. Then the questions turn to loss factor and mitigation. Sorry for bugging you guys . Will -----Original Message----- From: Steve Yao To: 'Ferrell, William'; 'Curtis Villamizar ' Cc: Steve Yao; ''mpls ' ' Sent: 3/17/03 12:17 PM Subject: RE: Between OSPF RSVP... Hi Will, Whether an RRO can fit into a Path/Resv message is dependent on a combination of various factors including, for example, large private objects. However, at this point, it appears that the likelihood of such a scenario is low. Steve >-----Original Message----- >From: Ferrell, William [mailto:William.Ferrell@titan.com] >Sent: Monday, March 17, 2003 10:49 AM >To: 'Curtis Villamizar '; Ferrell, William >Cc: ''Steve Yao ' '; ''mpls ' ' >Subject: RE: Between OSPF RSVP... > > > >Steve >Yes , you hit the nail on the head .. That was the "this" >In essence we're saying that risk is mititaged through >effective design and >numeric improbability, right. >Will > >-----Original Message----- >From: Curtis Villamizar >To: Ferrell, William >Cc: 'Steve Yao '; ''curtis@fictitious.org' '; 'mpls ' >Sent: 3/17/03 10:37 AM >Subject: Re: Between OSPF RSVP... > > >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>> >> > <<ATT01329.txt>> |
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