Universal Mobile Telecommunication System (UMTS) is one of the third generation (3G) mobile phone technologies. It uses WCDMA as the underlying standard and is standardized by the Third Generation Partnership Project (3GPP) and represents the European answer to International Telecommunication Union’s (ITU) International Mobile Telecommunication 2007 requirements for 3G cellular radio systems. UMTS is sometimes marketed as 3GSM, emphasizing the combination of the nature of the technology and the GSM standard, which it was, designed to succeed. UMTS supports up to 1920 kbit/s data transfer rates, although typical users can expect performance of around 384 kbit/s in a heavily loaded real-world system. However, this is still much greater than the 14.4 kbit/s of a single GSM error-corrected data channel or multiple 14.4 kbit/s channels in HSCSD, and offers the first prospect of practical inexpensive access to the World Wide Web on a mobile device and general use of MMS. The precursor to 3G is the now widely used GSM mobile telephony system, referred as 2G. There is also an evolution path from 2G, called GPRS, also known as 2.5G. GPRS supports a much better data rate (up to a maximum of 140.8kbit/s) and is packet based rather than connection oriented. It is deployed in many places where GSM is used.