Abstract: Disclosed is a system and method for transmitting data based on an operational state of a mobile station in a communication system. The method includes, when detecting a low battery state of the mobile station, storing one or more data packets to be transmitted to the mobile station, extracting at least one data packet, which has a transmission delay time larger than a difference between a maximum delay time and preset margin, from the one or more stored data packets, and transmitting at least a part of the extracted at least one data packet to the mobile station by using a resource allocated to the mobile station.

Abstract: Disclosed is a method and system for transmitting and receiving data in a communication system. The system includes a base station, and a relay station connecting the base station with at least one mobile station. The base station transmits data for a plurality of mobile stations to the relay station, and transmits the data to at least one mobile station belonging to the base station from among the plurality of mobile stations. The relay station receives the data from the base station, and transmits the data to at least one mobile station belonging to the relay station from among the plurality of mobile stations in the same interval as an interval where the base station transmits the data to the mobile station.

Abstract: An apparatus and method for performing effective Automatic Repeat reQuest (ARQ) in a multi-hop relay system is provided. The method includes the steps of determining whether a Mobile Station (MS) enters a handover region; if it is determined that the MS enters the handover region, transmitting an E2E-ARQ-Request message, which provides a notification that an End-to-End (E2E) ARQ method has begun to be used, to at least one of a Relay Station (RS) and the MS, transmitting to the RS an ARQ block to be transmitted to the MS, and storing the ARQ block in a queue; and if an Acknowledgement (ACK) for the ARQ block is received from the RS and if an E2E ACK which provides a notification that the MS has received the ARQ block is received from the at least one of the RS and the MS, discarding the ARQ block from the queue. Thus, excellent throughput and Media Access Control (MAC) efficiency can be obtained.

Abstract: Disclosed is a system and method for configuring an Internet Protocol) IP address in a communication system. The IP address configuration system includes a mobile station receiving a network advertisement message including network prefix information from a gateway, configuring the IP address by using the network prefix information, and transmitting a registration request message to the gateway after configuring the IP address; and the gateway creating the network advertisement message including the network prefix information, broadcasting the created network advertisement message, receiving the registration request message from the mobile station, creating a registration response message corresponding to the registration request message, and transmitting the created registration response message to the mobile station.