1. A method of determining whether to abort a prefetch operation, the method comprising: determining that an object is to be prefetched from a content server to a proxy server based on part on the probability that the object will be accessed by a client; prefetching, at the proxy server, the object from the content server, wherein the proxy server and the content server are in communication over a link between the proxy server and the content server, and wherein the prefetching, at the proxy server, the object from the content server comprises receiving the prefetched object at the proxy server; checking, in response to receipt of the prefetched object at the proxy server, the prefetched object to determine the prefetched object's size; determining a probability of use of the prefetched object; checking a link between the proxy server and a client to determine the link's bandwidth; based on the size of the prefetched object, the probability of use of the prefetched object, and the bandwidth of the link, determining, at the proxy server, whether prefetching of the prefetched object from the proxy server to the client should be aborted; and in response to determining that prefetching to the client of the prefetched object should be aborted, abstaining from forwarding the prefetched object from the proxy server to the client.