UK regulator Ofcom is to field-test the mobile broadband performance of five major operators. Ofcom told ZDNet UK that it had commissioned Epitiro, a broadband testing company, is to carry out the research due to growing customer dissatisfaction with actual — as opposed to advertised — mobile broadband speeds. Epitiro will measure data throughput speeds at UK operators 3, O2, Orange, T-Mobile and Vodafone..