y of the protocols are the same, but the functionality is different. These protocols carry signaling payload instead of the end-user traffic. The following protocols are different from the user plane protocols. GPRS Mobility Management and Session Management (GMM/SM) performs mobility management functions and connection activation, modification, and deactivation. GTP Control Plane (GTP-C) is the same for GPRS Tunneling Protocol (GTP) as the GMM/SM is for the GSM radio. 3G-GPRS The radio technology used by GSM did not provide very high bandwidth, and the industry had been preparing for some time for the new generation of mobile phone radio interface. The new technology was called UMTS and it is based on a new radio Basics of the 3GPP Technologies GMM/SM GMM/SM GTP-C GTP-C BSSGP BSSGP Network Network Service Service GSM RF GSM RF L1Bis L1Bis Figure 2.6 2G-GPRS control-plane protocols. NodeB Gn/Gp Packet Core Network Figure 2.7 3G-GPRS network architecture. technology - Wideband Code Division Multiple Access (WCDMA). The industry decided on specifying UMTS based on the GSM architectural principles, and reusing the GSM pro- tocols. However, due to the transition to the WCDMA technology, the RAN architecture (more specifically called UMTS Terrestrial Radio Access Network (UTRAN) in UMTS) had to be changed to meet the new requirements. The UMTS PS domain architecture - the 3G GPRS - is illustrated in Figure 2.7 [26]. The similarity of the 2G and 3G architectures is relatively obvious. The difference is in the level of abstraction in the RAN architecture. The 2G radio network elements BTS and BSC have been replaced in the 3G-GPRS architecture with UMTS base station (NodeB) and Radio Network Controller (RNC) respectively. In addition, there have been changes to the functionality split between the elements. In 2G-GPRS, the SGSN terminated the Deploying IPv6 in 3GPP Networks GTP-U GTP-U GTP-U GTP-U UDP/IP UDP/IP UDP/IP UDP/IP UTRAN Figure 2.8 3G-GPRS user-plane protocols. radio protocols. However, in UMTS the RNC terminate