Congestion Detection and Alleviation in Multihop Wireless Sensor Networks

Algorithm 1

Detecting node/link level congestion.

Initialization

: Consumed and Residual capacity of buffer, respectively

: Minimum interval between the two data packets

: The maximum buffer capacity

: Time interval between two consecutive data packets

: The sensor node to be congested

: Counter for the back-off period

: The level of consumed energy the node

: The maximum level of energy to be called as weak node

Detecting Congestion at Node-Level

() IF   OR

()   IF   is near to then

()    Discover less congested route discussed in [12]

()  ELSE IF   is near to OR between the route then

()    CALL: Ripple-based congestion control

()  ELSE IF  

()    CALL: Ripple-based congestion control

()  END IF

()  Send a notification message to predecessor nodes

() END IF

Detecting Congestion at Link-Level

() Generate a message (frame) to send to predecessor nodes

() IF  channel is free then

()  Send required data/control frame signals

() ELSE

()  

()  IF  

()    CALL: Ripple-based congestion control

()  ELSE

()    Time interval for the Back-Off

()  END IF

() END IF