MANET: Introduction Reference: “Mobile Ad hoc Networking (MANET): Routing Protocol Performance Issues and Evaluation Considerations”; S. Corson and J. Macker, RFC 2501, (rfc2501.htm)

2 Introduction Mobile Ad hoc Networking (MANET) –To support robust and efficient operation in mobile wireless networks by incorporating routing functionality into mobile nodes –Such networks are envisioned to have dynamic, sometimes rapidly-changing, random, multihop topologies which are likely composed of relatively bandwidth-constrained wireless links –Goal: to extend mobility into the realm of autonomous, mobile, wireless domains, where a set of nodes– which may be combined routers and hosts– themselves form the network routing infrastructure in an ad hoc fashion

3 Applications Industrial and commercial applications involving cooperative mobile data exchange “Wearable” computing and communications Combined with satellite-based information delivery –Provide an extremely flexible method for establishing communications for fire/safety/rescue operations or other scenarios requiring rapidly- deployable communications with survivable, efficient dynamic networking

4 Characteristics MANET –Autonomous system of mobile node –Nodes are equipped with wireless transmitters and receivers using antennas (omni-directional or highly directional, etc) Characteristics –Dynamic topologies –Bandwidth-constrained variable capacity links –Energy-constrained operations –Limited physical security –The need for scalability

5 Routing Issues Qualitative properties of routing protocols –Distributed operation –Loop-freedom –Demand-based operation –Proactive operation –Security –“Sleep” period operation –Unidirectional link support

6 Routing Issues (cont) Quantitative metrics –End-to-end data throughput and delay –Route Acquisition Time –Percentage out-of-order delivery –Efficiency  Average number of data bits transmitted/data bit delivered  Average number of control bits transmitted/data bit delivered  Average number of control and data packets transmitted/data packet delivered

7 Routing Issues (cont) Networking context –Network size (number of nodes) –Network connectivity (average number of neighbors of a node) –Topological rate of change –Link capacity –Fraction of unidirectional links –Traffic patterns –Mobility patterns –Fraction and frequency of sleeping node