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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: a question about the economics of peering
On Fri, 30 Nov 2001, David R. Dick wrote: :The problem with this idea is that public exchange points need :to be *avoided* when they get too congested. People may start :out trying to minimize number of hops, but I think they eventually :try to minimize total latency. Indeed. The notion of "hopcount" is objectively meaningless. You can count hops by physical wires, data segments, network hops, AS's or combinations of each (MPLS, GRE, PPP etc). He may have been trying to suggest the value of having a low latency path to a tier-1 provider, who may have low latency across their backbone and through their cores. But this is what you get with any good ISP, so I don't understand what makes IX's more special than being connected to UUNet, Exodus, or any other tier-1. In fact, having a connection to a tier-1, who may be at many IX's, would leave you with the benefits of diverse paths to other networks, without the premium of an IX. Especially considering the tier-1 would be doing traffic shaping to minimize latency across the backbone. Also, I wonder if you can measure latency reliably over time for more than 3 or 4 'hops' out, and relative to a small number of destinations, before your results cease to be relative to each other? I'm sure there is a principle like this acting upon the Internet somehow. Without latency measurements for the media you are counting hops in, you might as well count sheep. I think the engineer mentioned at the beginning of this thread was trying to hoodwink and bamboozle you. -- batz Reluctant Ninja Defective Technologies
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