Toward WMPLS Based Multicast Mechanism In Mobile Ad-Hoc Network

An ad hoc network is a network that is dynamically re-configurable,rapidly deployable, and does not depend on a fixed infrastructure or acentral administration.Efficient multicasting in Ad hoc network faces challenges notencountered in other types of networks such as the mobility of nodes,the tenuous status of communication links, limited resources, andindefinite knowledge of the network topology. In the designing space ofmulticast protocol, trade-offs must be made between some metricssuch as scalability and reliability, flexibility and generality, efficiencyand fairness etc. to reach a special objective.On the other hand, the application environments and connectionwith the Internet require that multicasting should supportQuality-of-Service . This is a more challenging requirement because ofthe inherent characteristics of Ad hoc network.MPLS as a QoS provisioning tool has emerged as an elegantsolution to meet the bandwidth-management and service requirementsfor next generation IP based backbone networks.We think that multicast and MPLS are two complementarytechnologies and multicasting over MPLS networks can benefit fromthe multicast reduce of traffic on one hand, and MPLS flexibility, speedand quality of service on the other hand.My thesis in this dissertation is that merging MPLS into multicastrouting protocol in mobile ad hoc network is not only a viable approach,but an elegant solution to enhance the network performance and anefficient solution for multicast scalability and control overheadproblems. To support my thesis statement , in this dissertation I present thedesign and evaluation of a new multicast protocol, the Label-SwitchingForwarding multicast routing protocol (LSF) for multi-hop wireless adhoc network, which is based on Wireless MPLS technology. To enable MPLS based multicasting, the multicast tree formationwith JOIN, LEAVE, DESTROY, and RPF message should be directlyimplemented in LDP signaling protocol. With new messages andextending of existing messages introduced to the CR-LDP, LSF setsup and maintains multicast forwarding state in an on-demand fashion.LSF 's features can be summarized as follows : LSF is designed to work independently of the unicast protocol used in the mobile ad hoc network and can thus work with any unicast protocol or even without a unicast protocol. LSF is completely distributed and does not rely on any centralized coordination or control. LSF adapts its behavior based on network conditions and application sending pattern, can automatically switch to appropriate forwarding topology (tree, mesh, and network-wide flood )to enable efficient multicasting. LSF uses no periodic control packet network-wide floods, periodic neighbor sensing, or periodic routing table exchanges. LSF uses label-driven packet forwarding mechanism toseparate control plane and data plane in the mobile ad hoc networks. All the features above are derived from the flexibility of label drivenpacket forwarding mechanism in MPLS. To enable completely separating of control plane and data plane inthe mobile ad hoc network, a framework for MAC layer multicastpacket forwarding is proposed in this dissertation. A forwarding node ina multicast group can shift the packet forwarding functionality awayfrom the host processor to the wireless network interface card. Thiswas made possible by carrying a label in the RTS/ACK control packetof the 802.11 DCF channel access scheme which allowed the MAClayer to determine the packet's next hop. Using this novel label-drivenpacket forwarding mechanism with LSF multicast architecture candramatically enhance the performance of the whole networks. Finally, we conducted an extensive performance evaluation ofLSF and ODMRP(on-demand multicast routing protocol) whichexplores the effectiveness of different multicast mechanisms in a widerange of mobile ad hoc network simulation scenarios. The results ofsimulation showed that LSF works well and generating less controlpacket overhead than ODMRP. Our study proved that using MPLS with multicast in the mobile adhoc network has many benefits not only for reducing multicastforwarding states but also for traffic engineering and QoS issues.Merging MPLS into multicast routing protocol in mobile ad hoc networkwill give rise to more potential advantages else, such as saving more...