Selective retransmission with network coding based on restricted block ACK information in wireless LAN multicast

Recently, multicast delivery of multimedia data via wireless LAN is increasing. Though IEEE 802.11 lacks the mechanism to recover packet loss in multicast, network coding (NC) has demonstrated its potential to retransmit lost packets efficiently. However, in existing NC methods, transmission delay becomes worse as the number of receiver stations increases because lost packets are continuously retransmitted until all stations receive them. In transmission of multimedia data, especially, transmission delay should be minimized. Therefore, we decrease transmission delay and improve its scalability for the number of receiver stations, at the expense of small packet loss acceptable for multimedia data.