at Mon, 13 Jan 1997 14:00:33 PST, you wrote:
You quote: "Although some of the packet loss is inadvertent, a large percentage of the public exchange point connectivity problems reflect intentional engineering decisions by Internet service providers based on commercial settlement issues.
I think that this is an _extremely_ dangerous assertion on Merit's part. As always, ascribing intent rather than raw data requires much more justification which I have yet to see.
Unfortunately, a key word here was probably left out. The sentence should have read "_may_ reflect"... Tony is right -- we cannot ascribe any motives/rational to ISP engineering decisions. We are walking a bit of a tightrope here. Although I believe the NetNow statistics contain some valuable information on network performance, a number of large ISPs have expressed significant concerns about the possible misinterpretation of the data. Specifically, several ISPs have explained that increasing amounts of their customer traffic do not traverse public exchanges. These ISPs assert that measuring packet loss/latency between public exchange points is not reflective of actual network performance as perceived by their customers. These ISPs further explained that their priority is always to optimize their customers' network performance. For the large ISPs, this increasingly may mean prioritizing connectivity to direct/private exchange points before public exchange points. Of course, I have not seen publicly available statistics on the amount of traffic traversing public exchange points versus private exchange points. The text Bob quotes essentially reiterates the explanations/descriptions of the NetNow data provided by the large ISPs. Lacking any evidence to the contrary, we included the text as an attempt to provide a more balanced view of the statistics.
Where is the data on packet losses experienced by traffic that does not go through public exchange points?
I suspect that you'd have to ask the parties involved in the private exchange point. I suspect that there are not such statistics currently kept, or if so, they would not be willing to disclose them. Thus IPPM...
A number of large ISPs have volunteered probe platforms at private exchange points. We (Merit/CAIDA/NLANR) are now evaluating the possible deployment of additional probe machines for inclusion in these network performance studies. - Craig -- Craig Labovitz labovit@merit.edu Merit Network, Inc. (313) 764-0252 (office) 4251 Plymouth Road, Suite C. (313) 747-3745 (fax) Ann Arbor, MI 48105-2785