Re: draft-ietf-ccamp-tracereq
Xiaoming Fu <fu@cs.uni-goettingen.de> Fri, 30 May 2003 23:19 UTC
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Date: Sat, 31 May 2003 01:19:48 +0200
From: Xiaoming Fu <fu@cs.uni-goettingen.de>
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To: Ron Bonica <Ronald.P.Bonica@mci.com>
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Subject: Re: draft-ietf-ccamp-tracereq
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Ron, It is a nice document. I went it through and have a few comments: - Section 3, 9) - "forwarding plane failu res" ==> _failures_ - I didn't understand why the following paragraph appears twice - the same in Section 3, 13) and 14). I assume you're talking about control plane failure in 13). Justification: MTU information is sometimes useful in identifying the root cause of forwarding plane failures. - Again, Section 3, 14): 14) When tracing through the forwarding plane, display the MTU associated with each hop in the reverse direction. Meanwhile, in Section 4.3: The protocol must be stateless. That is, nodes should not have to maintain state between successive traceroute messages. Are you assuming the probe and response messages are always hop-by-hop addressed? Otherwise, the forwarding and reverse paths of transporting the probe & response pair could differ, e.g., due to the Internet routing, or policies. And - Do we need a same transport path for them? If so, how a stateless traceroute protocol knows the reverse path to forward the response message? Probably we could create a temporary state while handling a probe message, to include P_HOP & Interface information like in RSVP, although the state is used only once in this case. - Section 4.1 - I don't understand the following sentense: Many network forward datagrams that specify IP options differently than they would forward datagrams that do not specify IP options. Maybe they ==> them, but the implication of this sentense is still unclear to me. - Section 4.2 "IP was _disqualified_ in order to conserve protocol identifiers." - I'm not sure this is always valid. Anyway, using UDP would have also to request a port number from IANA; there is actually a tradeoff among protocol_ID v.s. port number v.s. ICMP type. BTW, UDP may introduce a little (although minor) additional overhead. - In general I would expect the document would not constrain too much on protocol details - the latter looks to me more of a protocol design issue, instead of an informational RFC on "requirement". - It looks better if an experimental traceroute protocol (RFC1393 - traceroute using an IP option) would be referenced and shortly introduced in Section 2 (e.g., MTU determination). My 2 cents. Xiaoming Ron Bonica wrote: > Folks, > > At the request of the IESG, I have updated draft-ietf-ccamp-tracereq and > sent a new copy to the draft editor. Until the draft editor posts it, a copy > can be found at http://www.bonica.org/docs/draft-ietf-ccamp-tracereq-03.txt. > > Please take a look, as this draft will need to go through another WG last > call. > > =========================================== > Ronald P. Bonica Ph: 703 886 1681 > vBNS Engineering page: 1 888 268 8021 > Ashburn, Va. > =========================================== > "We are not on Earth to guard a museum, but > to cultivate a flourishing garden of life." > -- Angelo Giuseppe Roncalli > > -- Xiaoming Fu University of Goettingen, Telematics Group Lotzestr. 16-18, 37083 Goettingen, Germany Tel.+49-551-39 14411, Fax.+49-551-39 14403 http://www.ifi.informatik.uni-goettingen.de
- RE: draft-ietf-ccamp-tracereq Ron Bonica
- Re: draft-ietf-ccamp-tracereq Xiaoming Fu
- draft-ietf-ccamp-tracereq Ron Bonica
- RE: draft-ietf-ccamp-tracereq Ron Bonica
- Re: draft-ietf-ccamp-tracereq Kireeti Kompella
- Re: draft-ietf-ccamp-tracereq Kireeti Kompella
- Re: draft-ietf-ccamp-tracereq Xiaoming Fu
- RE: draft-ietf-ccamp-tracereq Ron Bonica
- Re: draft-ietf-ccamp-tracereq Xiaoming Fu