MAC/Routing design for under water sensor networks

The huge advances in communication technologies and Micro Electrical and Mechanical Systems (MEMS) have triggered a revolution in sensor networks. One major application of sensor networks is in the investigation of complex and uninhabited under water surfaces; such sensor networks are called the Underwater Wireless Sensor Networks (UWSN). UWSN comprises of a number of sensors which are submerged in water and one or several surface stations or a sinks at which the sensed data is collected. In some underwater sensor applications, autonomous underwater vehicles (AUVs) could be used. The underwater sensor nodes communicate with each other using acoustic signals. Applications for this type of networks include oceanographic data collection, pollution monitoring, offshore exploration and tactical surveillance applications. The novel networking paradigm of UWSN is facing a totally different operating environment than the ground based wireless sensor networks. This introduces new challenges such as huge propagation delays, and limited acoustic link capacity with high attenuation factors. These new challenges have their own impact on the design of most of the networking layers preventing researchers from using the same layers used for other networks. The most affected layers are the Physical, Medium Access Control (MAC), Routing and Transport layers. This work will introduce novel routing and MAC layers’ protocols for UWSNs. The routing protocol will adopt the minimum spanning tree algorithm and focus on maximizing the connectivity of the network, which means maximizing the total number of nodes connected to the root or the sink in this case. The protocol will try also to provide a minimum hop connection for all the nodes in the network taking into account the residual energy, location information and number of children at the next hop node. The other contribution of this work is a MAC Protocol which will incorporate the topology information provided by the routing protocol to minimize the collisions and energy wastage in data transmission. The MAC Protocol will also try to shorten the queuing delays at the intermediate nodes for a message traveling from source to the sink. A comparison will be conducted with other existing routing and MAC protocols. The routing protocol will be tested and compared with the E-Span spanning tree algorithm for data aggregation. The MAC protocol will be compared with Park\u27s protocol proposed in [2] in terms of performance metrics like end-to-end delay and the number of collisions. We will also explore the ability of the proposed protocols to enhance the life span of the network

The Impact of Adaptation Delays on Routing Protocols forMobile Ad-Hoc Networks (MANETs)

MANETs are coping with major challenges such as the lack of infrastructure and mobility which causes networks topology to change dynamically. Due to limited resources, nodes have to collaborate and rely packets on the behalf of neighbors to reach their destinations forming multi-hop paths. The selection and maintenance of multi-hop paths is a challenging task as their stability and availability depend on the mobility of participating nodes, where paths used a few moments earlier would be rendered invalid due to ever changing topology. The purpose of a routing protocol is to establish and select valid paths between communicating nodes and repair or remove invalid ones. As mobility rate increases, routing protocols spend more time in path maintenance and less time in actual data communication, degrading network performance. This interaction among mobility, topology and routing performance is usually empirically studied through simulations. This dissertation will provide a novel deep analytical study of the root cause of performance degradation with mobility. This is accomplished by, firstly, studying how mobility impacts durations of topology paths called Topological modeling. Secondly, analyzing how routing protocols adapt to topology changes in Adaptability modeling which identifies AdaptationDelays representing the time taken by a routing protocol to translate a change in topology to logical information used in path selection. Combining the results from these two studies, performance models of routing protocols are obtained, which later is used to optimize its operation. This study is applied on two tree-based proactive routing protocols, the Optimized Link State Routing and the Multi-Meshed Tree

A hybrid multi meshed tree routing protocol wireless ad hoc networks

Abstract A proactive routing protocol called Multi-Mesh Tree (MMT