* Sean Donelan:
If its not the content, why are network engineers at many university networks, enterprise networks, public networks concerned about the impact particular P2P protocols have on network operations? If it was just a single network, maybe they are evil. But when many different networks all start responding, then maybe something else is the problem.
Uhm, what about civil liability? It's not necessarily a technical issue that motivates them, I think.
The traditional assumption is that all end hosts and applications cooperate and fairly share network resources. NNTP is usually considered a very well-behaved network protocol. Big bandwidth, but sharing network resources. HTTP is a little less behaved, but still roughly seems to share network resources equally with other users. P2P applications seem to be extremely disruptive to other users of shared networks, and causes problems for other "polite" network applications.
So is Sun RPC. I don't think the original implementation performs exponential back-off. If there is a technical reason, it's mostly that the network as deployed is not sufficient to meet user demands. Instead of providing more resources, lack of funds may force some operators to discriminate against certain traffic classes. In such a scenario, it doesn't even matter much that the targeted traffic class transports content of questionable legaility. It's more important that the measures applied to it have actual impact (Amdahl's law dictates that you target popular traffic), and that you can get away with it (this is where the legality comes into play).