Design and investigation of scalable multicast recursive protocols for wired and wireless ad hoc networks

WAIT_TIME, after receiving the first reply in order to receive more than one
reply and select the best one according to present criteria.

• After choosing the path, node X will send a BNR_Down to refresh the
downstream members and sends upstream an eBNM message to find the previous
BNR and update its MFT table with this new connection.

• The upstream BNR will reply with rBNM to the new BNR and update its MFT.
At the end, the new tree construction is ready and the data packets flow will
continue.

5.7 Performance evaluation

5.7.1 Simulation

SARM protocol has been implemented in NS (version 2.29) simulator [1]. The
environment for this simulation comprised of 60 mobile nodes which are randomly
placed in a grid of size 1500m by 800m using random waypoint model [13]. For each
node after a pause time value assigned in advance a new destination and speed is given to
each node, and then each node moves towards the new destination with the assigned
speed. After a node reaches its destination, the same process is repeated until the end of
simulation. In this simulation the pause time changed with fixed group size. The pause
times used are varied between 0 & 400 seconds with 50s steps. Pause time 0 second
means that the nodes are in continuous movement. The value of the speed given to each
node is selected randomly from uniform distributed values with minimum value 0 m/s
and with maximum value of 10m/s. The network stack of each mobile node consists of
link layer, an ARP module, interface priority queue, IEEE 802.11, MAC layer with 250
meters transmission range, and a network interface.

Table 5.1 outlines the different simulation parameters used in the simulation.

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