Packet header size
This performance metric is to evaluate the scalability feature in the proposed protocol in
comparison to Xcast+ protocol. In this evaluation, both the packet header size in the source
node and for each data packet received is calculated. In the first part of evaluation, the
calculations were done to find the size of the header that initially encoded in the data packet
in the source node in order to send this data packet. Moreover, at the second part the
calculations were done to find the average header size encoded for each data packet from the
source to reach the destinations.
Figure 4.25 shows the results obtained for the first part of packet header size evaluation. It
can be noticed that SReM has got static header size even when the group size is increasing.
This result comes because whatever the group size SReM will only include the next
Branching Node Router (BNR) addresses in the header of each data packet. In Xcast+ the
results show that an exponential increase of header size when the group size increases. The
increase of header size will cause energy consumption in the intermediate node and a delay
of delivery packets, because the intermediate nodes will take long time and energy for
processing the header. In conclusion, SReM improve the scalability feature because the
header size is constant even when the group size increases.
Header size for data packets initialized in the source
node
♦ SREM
H Xcast+
Group Size (LMRsZReceivers)
Figure 4.25 Extra packet header size as a function of group size
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