A Sequence Number Prediction Based Bait Detection Scheme to Mitigate Sequence Number Attacks in MANETs

Algorithm 3

Operation of node after receiving RREP packet.

Procedure 1: Actions by the node after receiving an RREQ

Retrieve the Status of the node forwarding RREP packet

If (Status == malicious) then

Discard the RREP packet

End If

Else If (Status==normal) then

Evaluate the predictive seq. number (PRED_SEQNO)

End If

If (DEST_SEQNO > PRED_SEQNO)

Status=suspicious

(10) Update the Status of the node in the neighboring table.

(11) End If

(12) Else

(13) Perform the normal routing operations.

(14) If (Status = suspicious)

(15) Send BAIT_REQUEST to suspicious node

(16) End if

(17) If (BAIT_REPLY received)

(18) Change the status of the node from suspicious to malicious

(19) Delete the routing entry for the malicious node.

(20) Initiate a local route discovery process to find an alternate route to the destination.

(21) End If

(22) Else

(23) Change the Status from suspicious to normal and perform regular routing operations

(24) Exit