1. A method of controlling a rate at which requests from a client computer will be received by a server application, executed on a server computer, for processing, the method comprising the steps of: the server computer receiving a multiplicity of requests at a respective multiplicity of different times from the client computer and measuring a multiplicity of time intervals between different pairs of successive requests of the multiplicity of requests; the server computer determining a historical rate of requests from the client computer based in part on the multiplicity of time intervals; and based in part on the historical rate of requests from the client computer, the server computer determining and enforcing a limit on a rate for the server application to receive subsequent requests from the client computer for processing.