5. Architecture evolution towards NGN, IMS and MBMS

5.1 Release 99 architecture

The architecture of the first version of UMTS consists of a new access network (UTRAN) that can interconnect with the core network infrastructure of GSM and GPRS after a few upgrades. As the evolutions of the UTRAN have already been extensively described in the previous sections of this dossier, let's focus on those concerning the mobile terminal and the core network.

• Mobile terminal: from its very first version, UMTS has required a new user equipment (UE) comprising, on the one hand, the mobile equipment (ME), i.e. the cell phone (usually called the "3G mobile"), which contains a radio transmission unit as well as an application unit, and, on the other hand, the USIM card, which replaces the SIM card specific...