Mobile telephony has arrived on the scene.According to statistics of the International Telecommunications Union, in the mid-1990s, less than one person in 20 had a mobile telephone; as of 2003, this had risen to on p- son in five.In the mid-1990s, the GSM system was just being commerci- ized, there were serious coverage and interoperability issues that were not yet sorted out and handsets were only beginning to be something that did not require a...