Advanced join mechanism for multicast group management in DSRC-based ITS networks

In DSRC (dedicated short-range communication) based ITS (intelligent transportation system) networks, a number of mobile hosts can be densely distributed in an area, caused by traffic congestion. The majority of the mobile hosts require commonly useful information, such as traffic information, parking information and other driving-related information in such environment. It would be very effective to provide such information by using a common communication channel. In fixed networks, IP (Internet Protocol) multicasting is a well-known mechanism providing efficient point-to-multipoint data delivery. However, it does not handle mobile hosts as members of a multicast group. In this paper, we propose a base-station (BS) multicast group which consists of base stations accessed by mobile hosts that belong to a multicast group. Furthermore, we define new messages to control a BS multicast group based on the group management messages in IP multicasting. Managing the group members by control messages according to the movement of the mobile hosts eliminates packet loss during the mobile hosts' movement between base stations and reduces the amount of message traffic for multicast group management. We can show the effectiveness of our proposal by simulation results that show an improvement to the data-receiving rate (by more than 17%) and a reduction of the elapsed time (by more than 33%) for the completion of data received on the mobile hosts.