Sensor Networks

Media Access Control


Media access in sensor networks should be energy efficient and should also allocate bandwidth fairly to the infrastructure of all the nodes. They have little or no dedicated carrier sensing or collision detection and they have no specific protocol stacks which could specify the design of their media access protocol.

1 Alec Woo, David E. Culler A transmission control scheme for media access in sensor networks, Proceedings of the seventh annual international conference on Mobile computing and networking, July 2001

In this, the authors have proposed a solution to achieve fair allocation of bandwidth by controlling the originating data at a node when the traffic being routed through the node is high and controlling route-thru traffic when the originating data at a node is high. They alsopropose desynchronizing neighbouring nodes so as to avoid collisions.

2. Wei Ye, John Heidemann and Deborah Estrin An Energy-Efficient MAC Protocol for Wireless Sensor Networks, In Proceedings of the 21st International Annual Joint Conference of the IEEE Computer and Communications Societies (INFOCOM 2002), New York, NY, USA, June, 2002.

The authors look at overcoming major sources of energy wastage namely collisions, overhearing, control packet overhead and idle listening. For this, they propose synchronized listen and sleep periods to avoid idle listening and heavy control overhead and a contention based scheme to avoid collisions and overhearing.

Multipath Routing

The resilience of a protocol is measured by the likelihood that an alternate path exists between a source and a sink when the primary path fails. This can be increased by having multiple paths between the source and the sink but energy is consumed while keeping these alternate paths alive by sending periodic messages.So the resileince of the the network should be increased while keeping the maintenance overhead ofthese paths low.

1.Deepak Ganesan, Ramesh Govindan, Scott Shenker and Deborah Estrin Highly-Resilient, Energy-Efficient Multipath Routing in Wireless Sensor Networks ACM Mobile Computing and Communications Review, Vol. 5, No. 4, October 2001.

The authors propose use of braided multipaths instead of completely disjoint multipaths so as to keep the cost of maintaining themultipaths low. The costs of such alternate paths are also comparable to the primary path because they tend to be much closer to the primary path.

2. J.-H. Chang and L. Tassiulas, Maximum Lifetime Routing in Wireless Sensor Networks, Proc. Advanced Telecommunications and Information Distribution Research Program (ATIRP2000), College Park, MD, Mar. 2000.

The authors propose an algorithm which will route data through a path whose nodes have the largest residual energy. In this way, the nodes in the primary path will not deplete their energy resources through continual use of the same route thus achieving longer life.

3. Rahul C. Shah and Jan Rabaey, Energy Aware Routing for Low Energy Ad Hoc Sensor Networks IEEE Wireless Communications and Networking Conference (WCNC), March 17-21, 2002, Orlando, FL.

The authors propose use of a set of sub-optimal paths occasionally to increase the lifetime of the network. These paths are chosen by means of a probability which depends on how low the energy consumption of each path is.

4. Qun Li and Javed Aslam and Daniela Rus. Hierarchical Power-aware Routing in Sensor Networks In Proceedings of the DIMACS Workshop on Pervasive Networking, May, 2001

The path with the largest residual energy when used to route data in a network, may be very energy-expensive too. So, there is a tradeoff between minimizing the total power consumed and the residual energy of the network. The authors propose an algorithm in which the residual energy of the route is relaxed a bit to pick a more energy efficient path.

Hierarchy Based Routing

1.Qun Li and Javed Aslam and Daniela Rus. Hierarchical Power-aware Routing in Sensor Networks In Proceedings of the DIMACS Workshop on Pervasive Networking, May, 2001.

Groups of sensors in geographic proximity are clustered together as a zone and each zone is treated as an entity. Each zone is allowed to decide how it will route a message across.

2. Wendi Heinzelman, Anantha Chandrakasan, and Hari Balakrishnan,Energy-Efficient Communication Protocols for Wireless Microsensor Networks, Proc. Hawaaian Intl Conf. on Systems Science, January 2000.

The authors propose LEACH (Low Energy Adaptive Clustering Hierarchy) in which clusters have a moving cluster head so that the energy consumption is distributed more equally among all the nodes of the network and thereby achieve graceful degradation. Different nodes become the cluster head in a cluster in different rounds.

Query based routing

In this, the destination nodes propogate a query for data(sensing task) from a node through the network and a node having this data sends the data which matches the query when it receives the query. All the nodes have tables consisting of the sensing tasks queries that it receives and send data which matches these tasks when they receive it.

1.David Braginsky and Deborah Estrin Rumor Routing Algorithm For Sensor Networks Under submission to International Conference on Distributed Computing Systems (ICDCS-22), November 2001.

2. Chalermek Intanagonwiwat, Ramesh Govindan and Deborah Estrin . Directed Diffusion: A Scalable and Robust Communication Paradigm for Sensor Networks In Proceedings of the Sixth Annual International Conference on Mobile Computing and Networks (MobiCOM 2000), August 2000, Boston, Massachusetts.

Negotiation based protocols

These protocols use high level data descriptors for to eliminate redundant data transmissions through negotiation. Communication decisions are also taken based on the resources that are available to them.

1.Wendi Rabiner Heinzelman ,Joanna Kulik , Hari Balakrishnan Adaptive protocols for information dissemination in wireless sensor networks Proceedings of the fifth annual ACM/IEEE international conference on Mobile computing and networking, August 1999

2 Joanna Kulik , Wendi Heinzelman , Hari Balakrishnan . Negotiation-based protocols for disseminating information in wireless sensor networks Wireless Networks March 2002

Surveys

1. Elizabeth M. Royer, Chai-Keong Toh, A Review of Current Routing Protocols for Ad Hoc Mobile Wireless Networks, IEEE Personal Communications, Vol. 6, No. 2, pp. 46-55, April 1999.

2. Praveen Rentala, Ravi Musunnuri, Shashidhar Gandham, Udit Saxena, Survey on Sensor Networks

Others

1. Suresh Singh , Mike Woo , C. S. Raghavendra Power-aware routing in mobile ad hoc networks Proceedings of the fourth annual ACM/IEEE international conference on Mobile computing and networking, October 1998

2. J.-H. Chang and L. Tassiulas, "Routing for maximum system lifetime in wireless ad-hoc networks," Proceedings of 37-th Annual Allerton Conference on Communication, Control,and Computing, Monticello, IL, Sept. 1999.