Performance Enhancement of IEEE 802.11s Mesh Networks using Aggressive Block Ack Scheme

Enhanced distributed channel access (EDCA), a medium access function of the IEEE 802.11e, has been suggested for applying in the IEEE 802.11 based wireless mesh network (WMN). The block acknowledgement (block ACK) feature of EDCA can be applied for the communication between the WMN nodes to overcome overheads by reducing the number of control packets for multiple data transmission. However, using block ACK, the performance in terms of throughput might degrade due to the presence of hidden/exposed nodes. Lengthy medium reservation by communicating nodes and lack of proper knowledge of ongoing transmission in neighboring nodes leads to under-utilized resources. Additionally, fairness among the nodes is another problem in the block ACK scheme. In this paper we introduce a simple but effective method to tackle the hidden/exposure terminal problem thus increasing the performance in terms of throughput and fairness.