2 research outputs found
Constructive Relay based Cooperative Routing in Mobile Ad hoc Networks
PhDMobile Ad hoc networks (MANETs) are flexible networks that transmit packets node-by-node along a route connecting a given source and destination. Frequent link breaks (due to node mobility) and quick exhaustion of energy (due to
limited battery capacity) are two major problems impacting on the
flexibility of MANETs. Cooperative communication is a key concept for improving the system
lifetime and robustness and has attracted considerable attention. As a result, there
is much published research concerning how to utilize cooperative communication
in a MANET context. In the past few years, most cooperative technologies have focused on lower layer enhancements, such as with the Physical Layer and MAC Layer, and have become very mature. At the Network Layer, although some research has been proposed, issues still remain such as the lack of a systematically designed cooperative routing scheme (including route discovery, route reply, route enhancement and cooperative data forwarding), the use of cooperative communication for mobility resilience, and route selection (jointly considering the energy consumption, energy harvesting potential and link break probability).
Driven by the above concerns, a novel Constructive Relay based CooPerative
Routing (CRCPR) protocol based on a cross-layer design is proposed in this thesis.
In CRCPR, we fi rst modify the traditional hello message format to carry some
additional neighbour information. Based on this information, a key aspect of this
protocol is to construct one or more small rhombus topologies within the MANET
structure, which are stored and maintained in a COoPerative (COP) Table and
Relay Table. Next, the route request procedure is re-designed to improve resilience
to node mobility with a scheme called Last hop Replacement. Finally, assuming
nodes are mostly battery-powered, destination node based route-decision criteria
are explored that can consider energy consumption, energy harvesting and link
break probability to determine an appropriate route across the MANET.
As the hello message format is modi ed to carry additional information, the
control overhead is increased. However, in order to improve the control message
eficiency, a new generalised hello message broadcasting scheme entitled Adjust
Classi ed Hello Scheme is developed, which can be deployed onto every routing
protocol employing a hello mechanism.
As well as designing a new routing protocol for MANETs, including route discovery,
route selection, route reply, route maintenance, route enhancement and cooperative
data forwarding, the proposed scheme is implemented within an Opnetbased
simulation environment and evaluated under a variety of realistic conditions.
The results con rm that CRCPR improves mobility resilience, saves energy via
cooperative communication and reduces the control overhead associated with the
hello message mechanism.Chinese Scholarship Counci