Multipath On-demand Routing
Encyclopedia
The Multipath On-demand Routing (MOR) protocol is a protocol to connect nodes in wireless sensor network
s. It is an Ad Hoc Routing Protocol which is reactive
or on-demand, meaning that it establishes routes as needed. The advantage of this approach is obvious if only a few routes are needed, since the routing overhead is less compared to the proactive approach of establishing routes whether or not they are needed. The disadvantage of on-demand establishment of routes is that connections take more time if the route needs to be established.
MOR lessens the disadvantages of on-demand routing in wireless sensor networks by having the likely targets of communication perform an initial broadcast. This allows all recipients to have a route to these nodes.
The main characteristic distinguishing MOR from other ad-hoc routing protocols is that it maintains multiple routes to each destination, when available, whereas most other such protocols only keep a single route. There are many advantages to having multiple routes when possible, including
Each node in MOR remembers all next-hop nodes that are closer to a given destination for which a route exists. It then sends successive packets to each such node in round-robin
fashion. If a next-hop node fails to acknowledge a given packet, the retransmission is attempted to another node, again if possible. This allows automatic and graceful recovery from occasional localized congestion
as well as longer-term reasons for node unavailability.
Wireless sensor network
A wireless sensor network consists of spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperature, sound, vibration, pressure, motion or pollutants and to cooperatively pass their data through the network to a main location. The more modern...
s. It is an Ad Hoc Routing Protocol which is reactive
Reactive
Reactive may refer to:*Generally, capable of having a reaction*Reactance , the imaginary component of AC impedance*Reactive mind*Reactive programming...
or on-demand, meaning that it establishes routes as needed. The advantage of this approach is obvious if only a few routes are needed, since the routing overhead is less compared to the proactive approach of establishing routes whether or not they are needed. The disadvantage of on-demand establishment of routes is that connections take more time if the route needs to be established.
MOR lessens the disadvantages of on-demand routing in wireless sensor networks by having the likely targets of communication perform an initial broadcast. This allows all recipients to have a route to these nodes.
The main characteristic distinguishing MOR from other ad-hoc routing protocols is that it maintains multiple routes to each destination, when available, whereas most other such protocols only keep a single route. There are many advantages to having multiple routes when possible, including
- increased reliabilityReliability (computer networking)In computer networking, a reliable protocol is one that provides reliability properties with respect to the delivery of data to the intended recipient, as opposed to an unreliable protocol, which does not provide notifications to the sender as to the delivery of transmitted data.A reliable...
- potentially better load balancingLoad balancing (computing)Load balancing is a computer networking methodology to distribute workload across multiple computers or a computer cluster, network links, central processing units, disk drives, or other resources, to achieve optimal resource utilization, maximize throughput, minimize response time, and avoid...
- more even energy consumption (a consequence of better load balancing)
Each node in MOR remembers all next-hop nodes that are closer to a given destination for which a route exists. It then sends successive packets to each such node in round-robin
Round-robin
The term round-robin was originally used to describe a document signed by multiple parties in a circle to make it more difficult to determine the order in which it was signed, thus preventing a ringleader from being identified...
fashion. If a next-hop node fails to acknowledge a given packet, the retransmission is attempted to another node, again if possible. This allows automatic and graceful recovery from occasional localized congestion
Network congestion
In data networking and queueing theory, network congestion occurs when a link or node is carrying so much data that its quality of service deteriorates. Typical effects include queueing delay, packet loss or the blocking of new connections...
as well as longer-term reasons for node unavailability.