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has used the cross layer design technique for routing layer to access the energy
parameter from the lower layer. The Network Simulation 2 (NS-2) is employed to
analyst the results between EW-AODV and AODV.
This article describes the operation of wireless sensor networks on IEEE 802.15.4
standards, AODV routing protocol and Cross layer design method in Section 2. The
EW-AODV describes in Section 3. The simulation parameters and network topology
using NS-2 network are presented in Section 4. The performance analysis and
comparison are present in Section 5. The conclusion is described in Section 6.
2
Theory
2.1
IEEE 802.15.4 Standard
IEEE 802.15.4 [3] is a standard which specifies the physical layer and media access
control (MAC) for low-rate wireless personal area networks (LR-WPANs). The basic
framework conceives a 10-meter communication range with a transfer rate of 250
kbps. Trade-offs is possible to favor more radically the embedded devices with the
low power requirements, through the definition of not one, but several physical layers.
The transfer rates of 20 and 40 kbps were initially defined, with the 100 kbps rate
being added in the current revision. This standard supports topology one-hop star and
multi-hop with the frequency band at 2.4 GHz or 896/915 MHz size of payload 104
bytes and address length 64 bit or 16 bit (support 65,000 nodes. The sensor can
communicate using multi-hop and also required a routing protocol to manage the path
and send the information.
2.2
Ad hoc On-Demand Distance Vector (AODV) Protocol
AODV [4] Routing is a routing protocol for mobile ad hoc networks (MANETs).
AODV is a reactive routing protocol, meaning that it will establish a route to a
destination only on demand. AODV find a routing path independently of the usage of
the paths. At that point, node has to broadcast a request for a connection. The
advantage of AODV is that there is no overhead traffic for the communication along
the existing links. Also, the distance vector routing is simple, and doesn't require
much memory or calculation. However, AODV still requires more time to establish a
connection, and the overhead of the initial communication to establish a route is
heavier than some other approaches. Fig. 1 show AODV Route Discovery, Node 0 is
source node and Node 7 is a destination node. Nodes 0 start to broadcast a route
request packet (RREQ) to the neighbors node, When the neighbors receive RREQ, it
will check in the route table. If there is no route to a destination, AODV will
broadcast to other neighbor nodes. When the destination node receives RREQ, it will
send a route reply (RREP) to the source node. As we can be seen, the AODV
protocols produce a large amount of control message when the route discovery is
activated. Therefore, the energy is consumed. In this research, the energy saving
routing protocol using cross layer design is proposed.
