204 ◾ Security for Multihop Wireless Networks
for beacons (probe responses) from the nodes. After the remaining nodes send the
probe response, the CH initiates association and allocates a specified time slot for
each of the sensor nodes to transmit to the CH.
e sensor nodes start transmitting in their allotted time slot using TDMA
and this marks the beginning of the steady phase. When all nodes within an intra-
cluster region finish the transmission of aggregated data to the CH, the forward-
ing phase begins. e forwarding phase marks the beginning of the intercluster
communication where CH performs computation on the received data. CH also
transmits the data using multiple-chain multihop approach to the neighboring CH
until the data is rec