10. The charging system of claim 1 further comprising: a billing processor for generating communication service charging data for at least one communication service in response to the charging data messages and the charging topics.
10. The charging system of claim 1 further comprising: a billing processor for generating communication service charging data for at least one communication service in response to the charging data messages and the charging topics. 13. The charging system of claim 10 wherein the billing processor is arranged to combine charging data from a plurality of charging proxies when generating the communication service charging data for the at least one communication service.