Limit traffic or bandwidth per sub-site.

Hello

Is there any possible way to limit the amount of traffic, unique visitors, page views or bandwidth per sub-site with Pro Sites or any other plugin?

We don't want one sub-site to be able to overload the servers with high amounts of traffic, which would affect other sub-sites. If so, we'd like to have them upgrade to a higher package to gain more traffic.

Thanks

Elliot