North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: concern over public peering points [WAS: Peering point speedpublicly available?]
On 7/5/04 1:18 AM, "Steve Gibbard" <[email protected]> wrote: > > > The performance arguments are probably more controversial. The arguments > are that shortening the path between two networks increases performance, > and that removing an extra network in the middle increases reliability. > The first argument holds relatively little water, since it's in many cases > only the AS Path (not really relevant for packet forwarding performance) > that gets shortened, rather than the number of routers or even the number > of fiber miles. If traffic goes from network A, to network A's router at > an exchange point, to network C, that shouldn't be different > performance-wise from the traffic going from network A, to Network B's > router at the exchange point, to Network C. Assuming none of the three > networks are underprovisioning, the ownership of the router in the middle > shouldn't make much difference. The reliability argument is probably more > valid -- one less network means one less set of engineers to screw > something up, but the big transit networks tend to be pretty reliable > these days, and buying transit from two of them should be quite safe. > I believe that peering does lead to a more robust network and somewhat better performance. Being heavily peered means that when one of my transit providers suffers a network 'event', I am less affected. Also, just because I'm sitting at a network exchange point (and take my transit there) doesn't mean that's where my transit networks peer. Quite often, I see traffic going to Stockton or Sacramento through one of my transit connections to be delivered to a router just a few cages away at PAIX. > The pricing issues are simpler. There's a cost to transit (which is, to > some degree, paying some other network to do your peering for you), and > there's a cost to peering. Without a clear qualitative difference between > the two, peering needs to be cheaper to make much sense. The costs of > transit involve not just what gets paid to the transit provider for the IP > transit, but also the circuit to the transit provider, the router > interface connecting to the transit provider, engineering time to maintain > the connection and deal with the transit provider if they have issues, and > so forth. Costs of peering include not just the cost of the exchange > port, but also the circuit to get to the exchange switch, sometimes colo > in the exchange facility, engineering time to deal with the connection and > deal with the switch operator if there are issues, and time spent dealing > with each individual peer, both in convincing them to turn the session up, > and dealing with problems affecting the session. Even if the port on the > exchange switch were free, there would be some scenarios in which peering > would not be cheaper than transit. > When we established our connection at PAIX, peering bandwidth was a factor of 20 cheaper than transit. Now they're at parity. Unfortunately, some *IX operators haven't seen fit to become more competitive on pricing to keep peering more economical than average transit pricing. $5000 for an ethernet switch port? It makes me long for the days of throwing ethernet cables over the ceiling to informally peer with other networks in a building. In the 'bad' old days of public exchanges (even the ad hoc ones), most of the problems were with the design and traffic capacity of the equipment itself (not a real problem now), not with actual 'operations'.
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