There are two types of wireless networks, infrastructure wireless network and wireless Ad-hoc networks. Wireless Ad-hoc networks are well suited for use by emergency response teams, for search and rescue operations that require team- based communications in the absence of working telecommunications infrastructure, while infrastructure networks require the existence of access point in which all the communications are done through it. Unfortunately, wireless Ad-hoc networks suffer from limited bandwidth and QoS constraints. A Priority eXplicit multiCAST based routing protocol (P-XCAST) is presented in this paper to support team-based many-to-many communications in wireless Ad-hoc networks. eXplicit multiCAST (XCAST) is well suited for supporting a large number of small groups effectively, in comparison with multicast based protocols. However, since XCAST was initially designed for wired networks, it was not optimized for wireless Ad-hoc network use. The proposed P- XCAST protocol enhances XCAST for wireless Ad-hoc network use by modifying the route request mechanism in AODV to build the network topology, and route data packets containing the list of destinations for a given group in the XCAST header, by classifying the destinations according to similarities in their next hop neighbors and hop counts. A single data packet is XCAST in lieu of sending n unicast data packets to n destinations with the same next hop neighbor. In addition, P-XCAST is merged with a new mobile group management protocol to handle mobility of group members. In this paper, P-XCAST was tested using topologies with different sources that were sending and receiving data at the same time to handle foreground and background many-to-many applications. The results of simulation experiments show that P-XCAST achieved better QoS performance compared with other routing protocols for small group sizes typical of group communications applications such as Push-To-Talk (PTT).
['Faisal Y. Alzyoud', 'Tat-Chee Wan']
The Effect of Using P-XCAST Routing Protocol on Many-to-Many Applications