"Nigel Taylor" All, > I just got through some of the presentations linked from the recent >nanog >meeting. The draft in question was presented by Henk Uijterwaal titled "New >Services from RIPE NCC. > >There is also this link on the nanog list to his latest draft. > >http://www.ripe.net/home/henk/draft-ietf-ippm-owmetric-as-01.txt > >I was just thinking about some of our current tools like ping, hping, and >traceroute which measures round trip delay vs one-way delay. RFC 2679 >discusses numerous reasons for calculating one-way delay, however would >tools >like ping and traceroute with the existence of ping6 and traceroute6 be >rfc2679 compliant. I've not done any research at this point but, would >operational tools in everyday use benefit from this new active measurement? > >Here's a pretty good link that explains the concept for the "normal" folks >like myself.
There are several problems with using timestamped measurement in the router itself. Some of these may be reduced with IPv6, but, for others, external passive hardware or special router hardware seems necessary. See our BGP convergence drafts, http://www.ietf.org/internet-drafts/draft-ietf-bgpconv-03.txt and http://www.ietf.org/internet-drafts/draft-ietf-bgpbas-00.txt First, routers may not give sufficient precision in measurement, because they rate-limit ICMP to protect against ICMP floods, or simply don't prioritize it highly. I mention IPv6 because authenticated source addresses may be used without fear of denial of service. Second, the router may or may not have the capacity to capture and store a statistically valid amount of data. NetFlow data export, for example, summarizes to a degree. If you could shoot debug to syslog, you'd have a much better chance as long as the router could keep up with it, using something like a SPAN port. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=56576&t=56560 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
