AODV Routing Protocol Source Code Implementation

AODV (Ad-hoc On-Demand Distance Vector) is a widely used routing protocol for Mobile Ad-hoc Networks (MANETs). It employs an on-demand route discovery mechanism that establishes routes only when the source node needs to send data, thereby reducing network overhead.

The core protocol logic includes Route Request (RREQ) and Route Reply (RREP) mechanisms. When a source node lacks a valid route to the destination, it broadcasts RREQ messages. Intermediate nodes can either respond to RREQ or continue forwarding until the destination node receives the request and returns an RREP. Code implementation typically involves creating RREQ packet structures with fields like source/destination IPs, sequence numbers, and hop counts. Additionally, AODV maintains routing tables and handles link failures through Route Error (RERR) messages. The routing table implementation requires data structures to store next-hop information, destination sequences, and route lifetimes.

By avoiding continuous route updates, AODV effectively reduces bandwidth consumption, making it suitable for dynamically changing wireless network environments. Implementation typically involves key functions such as neighbor discovery through hello messages, sequence number management to prevent routing loops, and route maintenance mechanisms that monitor link connectivity and trigger RERR messages when failures are detected, ensuring efficient packet delivery.