[e2e] Open the floodgate

[Christian Huitema]

> If don't want the transport layer to do congestion control, what layer
do
> you want to do it? 

The problem with a strict transport-layer approach is that transport
actors may well have an incentive to cheat and maximize their immediate
satisfaction, either by hacking the TCP code or by using many
connections instead of one. The control loop that prevents cheating is
somewhat loose. Social pressure works well against large actors like
implementers of operating systems, but it works less well with small
actors, e.g. developers of specific applications or teen-age hackers.

If you want an approach that resists gaming, you probably need to
involve the network. After all, while transport actors have an incentive
to maximize their own satisfaction, network actors have an incentive to
maintain an orderly usage of resource. For example, you would want to
implement a response function in the network where abuse of a congested
link would lead to a lesser goodput than playing by the rules. Once you
have an adequate response function in the network, then transport
writers can be as creative as they want, since their self-interest would
drive them to optimal social benefit.

-- Christian Huitema