consider to compare proposed protocol, for instance,
throughput maximization is not as important for
event-based application as it for monitoring
application. One of the important challenges for
real-time surveillance system is end-to-end delay
QoS for packet deliveries. Providing end-to-end QoS
is difficult due to two reasons. As wireless sensor
nodes may require multihop transmissions to reach
the sink and the some of the wireless transmissions
may be not successful. Load balancing is used to
increase network lifetime by reducing energy
consumption in wireless sensor networks. Some
papers considered the overview of load balancing
algorithm. Using clustering for load balancing can
also decrease energy consumption and increase
network lifetime and scalability. The cluster head
needs to send aggregated data to the base station. It
consumes more energy for data aggregation than the
member nodes.
In my network, the nodes are randomly deployed
and gather information by its sensor and periodically
send it to a sink node. To send node data to sink,
each node sends data to a neighboring node which is
nearer to the sink. Other neighbors go to sleep until
transmission ends. We propose a cross-layer design
to increase network lifetime. This protocol divides
the network to several levels. Each level shows the
distance between the node and the sink. Each node
acquires its level in the initial phase. After the initial
phase, the node knows the number of hops to the
sink node. For instance, a node neighboring the sink,
knows that there is not any hop between itself and
the sink node. Thus the node sets its level to ‘one’. A
node, neighboring the ‘level-one’ node and is not a
neighbor of the sink node, knows that it is one hop
away from the sink node and then sets its level to
‘two’ and the rest of the nodes set their levels
likewise.
When the surveillance system needs to provide
end-to-end delay QoS, We propose new algorithm
providing end-to end delay QoS. This protocol uses
a route table and only a first initial phase for sending
data to sink. A node operates the same as the
aforementioned first initial phase with the exception
that it saves the mac address of each get-level
massage receiving from the lower level nodes. Each
nodes estimate Minimum Delay Time (MDT) that it
can deliver a packet to sink and knows the MDT of
its lower level neighbor. It finds the minimum MDT
of its lower level neighbor and selects this lower
level neighbor for next hop to send a packet. For
providing the end-to-end delay QoS, a delay field is
inserts to data packet and when the delay field value
become bigger than end-to-end delay QoS, this
packet is discarded. For end-to-end delay QoS, when
a node generates a data and send it form the
application layer to the cross layer, the cross layer
inserts a delay field to the data packet. This field is
henceforth called delay field throughout the present
paper. Each node adds a delay time, which a packet
stays in the queue until it is sent, to delay field.
When a node receives a data packet, it checks the
sum of the delay field and Minimum Delay Time
(MDT), which the node can deliver a packet to the
sink and the detailed descriptions are explained in
the following paragraph. If the result is bigger than
the admissible end-to-end delay, the packet is
discarded otherwise the receiver node push the
packet to its queue. The RTS/CTS handshaking is
used to data transmission. This transmission is the
same as the previous section but in this case, the
sender node select the next hop from its route table
therefore there is no longer receiver contention to
send CTS packet. The next hop is the node that its
MDT is minimum value in the route table. Each
node sends the packet that its delay field is
maximum value in the queue.
4 SIMULATIONS
We evaluate our proposed cross-layer protocols
using MIXIM package and Omnet++ simulator.
Each sensor node periodically samples the data and
sends it to sink node. The simulation result for 10
random network topologies with 100 sensor nodes in
400*400 m2 area is presented with the sink position
(250,250). When sensor node samples data with low
rate, the energy consumption is high. In low
sampling frequency, when data rate increases, the
average energy consumption decreases severely.
After the node sends its data, it stays awake and
listens to the channel until the next transmission
starts. The node wastes energy in this time. When
data rate increases, the time the node stays awake
and wastes its energy in a way that energy efficiency
of the node increases. In order to solve this problem,
many papers use duty cycle mechanism. This
mechanism increases the delay and is designed for
low rate data but our aim is to support the big data.
In high data rate, the energy efficiency of the node
slowly increases because the node has to be more
competitive for getting channel. The second initial
phase has a significant impact on average energy
consumption. It tries to balance energy consumption
through the network therefore the local congestion
decrease and energy efficiency increase. When the
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