RLT Code Based Handshake-Free Reliable MAC Protocol for Underwater Sensor Networks

Algorithm 2

Collecting the state information of neighbor node.

()    INPUT: overhear a frame from a neighbor

()    OUTPUT: refresh the state of the neighbor’s in neighbor table

()    Upon  overhearing a frame  do

()        if  (not an ACK) & (the sequence number >1)  then

()        set the state of the neighbor to “0”;

()       else if  (not an ACK) & (the sequence number = 1)  then

()        set the state of the neighbor to “3”; // indicates the unknown state

()       else if  (is an ACK with null index)  then

()        set the state of the neighbor to “2”; // indicates the unknown state

()    else if  (is an ACK) & (the value of index field is “0”)  then

()      set the state of the neighbor to “1”; // ready to receive frames from other nodes

()    endif

() endupon