There is an explosive growth in data demand from the iPhone 4S that is in part related to the personal "virtual assistant," Siri, reveals a study by Arieso, a British technology company that specializes in bandwidth optimization. According the study, "iPhone 4S users are the 'hungriest' data consumers, demanding twice as much data as iPhone 4 users and three times as much as iPhone 3G users." And just two weeks after the 4S release, Ars Technica noticed a jump in data usage and warned "it could force you over your monthly data quota with your cell carrier if you're not careful."  With modest use of Siri, Ars Technica was able to generate 20MB of data usage within a 30 day period. But Siri might not deserve all the credit. Other factors also contribute to the 4S increased data usage, according to ZDNet. For one, the 4S runs with a dual-core A5 processor making it the fastest cell phone on the market, which means more can be done in less time and so more data can be consumed in less time. Also the better antenna means that users have greater access to cellular networks, which will add a greater likelihood of using the network. Also iOS5 comes installed on the 4S which optimizes iCloud and streaming music, both of which gobble up data. The increased usage is straining cellular networks. "(Cellular network) operators risk spiraling and misplaced operational expenditure and delivering a sub-par quality of experience to customers," said Arieso.