Servicing mobile hosts over the Internet has some problems including nodes' location, independent addressing, address conversion and packet forwarding as well as mobile host's location management. However, packet transmission and independent addressing in the mobile environments are very similar to the ones in the multicasting environment. So, in this paper, we propose a new scheme about how to manage the multicasting group and to set the communication path in the mobile environment by applying two-level addressing mode, which is similar to mobile IP, for lcation-independent address setting. More specifically, we propose the smooth handoff scheme that minimizes the handoff delay. To check the performance of our proposed scheme, we modified the NS-2 network simulator and as a result, we showed that our proposed scheme is better than other techniques in terms of transmitted packets' throughput.