Shared GTP tunnels for multicast data in 3G networks

With the evolution of communication technology, 3G networks claim to provide bandwidths of up to 144 kbps to 2 Mbps. On the other hand, the latest mobile handsets are equipped with novel devices such as cameras. It is easy to foresee diverse multimedia services, e.g. on-line live sports events, on-line games. Then, as bandwidth-consuming multimedia services become popular, resources in the core network and the radio network become scarcer. The multicast mechanism was designed to economize network resources in the Internet when data are sent to multiple users at the same time. To apply the same concept to 3G networks, a new multicast mechanism must be designed because of the innately different network architecture. In 3G networks, two GTP (GPRS tunnel protocol) tunnels are built for each connection. According to the standard procedure, for users in the same multicast group, different tunnels are built for each user even when they are within the same cell. The procedure results in multiple unicast connections. That does not carry out multicast. The main contributions of our proposed mechanism are hierarchical multicast group management and shared GTP tunnels in the core network.