Sthabile Lushaba

                    Investigating a Blackhole Attack Solution in Mobile Peer-to-Peer 

                                               Networks with AODV Routing Protocol

Brief introduction :

The  AODV routing protocol is a reactive protocol where routes are only determined when needed. Due to the mobility of nodes in mobile peer-to-peer networks, two communicating nodes are bound to not be within each other's transmission range. Due to this, data transmission occurs via multicasting.  The AODV routing protocol consists of two main mechanisms, namely, route discovery and route maintenance.  The route discovery process is initiated by the source node when there is a need to transmit data packets. The AODV routing protocol uses Route Request (RREQ) and Route Reply (RREP) packets during the route discovery process. A source node broadcasts an RREQ packet in search for a route to a particular destination, neighboring nodes that know the route reply with RREP packets. Each packet has a sequence number and hop count field. The source node compares all the RREP packets received and selects the best route based on the highest sequence number and lowest hop count.

A blackhole node attaches itself to the network by sending route replies with an arbitrarily high sequence number and the lowest hop count of one. The source node then selects the malicious node and sends data packets through that route. The detrimental feature of the blackhole attack is that the malicious nodes drop the data packets instead of forwarding to the intended destination. The affects the overall quality of service. 

In this research, the blackhole attack is investigated and a dynamic sequence number threshold based solution is explored. A mobile network is simulated using the NS3 , the blackhole attack and solution were implemented by modifying the source code provided by the NS3. 

The

The source code has been made available at : https://github.com/sthabile/honours_project.git