Performance Metrics

Performance metrics

In order to compare the performance of a specific routing protocol on two distinct network sizes the following performance metrics are used:

• AODV Route Discovery Time: This statistics refers to the time taken to discover a route to a specific destination. This is the time between sending a route discovery request message and getting a reply with route to the particular destination. Lower the route discovery time the better the performance.

• OLSR Route Table Calcs: The route table re-calculation takes place whenever neighborhood or topology change is detected on a node. The more calculations take place the more MANET node resources will be used.

• OLSR MPR Calcs: MPR re-calculation in OLSR happens whenever neighborhood change is detected on a node. The more calculations take place the more MANET node resources will be used.

In order to compare the performance of the two routing protocols against each other, the following performance metrics are used:

• TCP Retransmission Count: The TCP retransmission occurs when TCP assumes there is congestion on the network. This is not always the case, but from TCP’s perspective the congestion at the receiver end caused the TCP segment to get lost and be unacknowledged. In MANET many factors cause TCP retransmission to occur such as unexpected delays caused by broken routes, hidden/exposed node problems and dynamic topology. TCP performance is very important since it’s the only protocol in the TCP/IP suite that provides reliable data delivery over the network. MANET nodes use TCP/IP and the MANET applications requiring reliable data delivery such as email and FTP depends on TCP for guaranteed data delivery. Lower the TCP retransmission count the more reliable the network is likely to be.

• FTP Traffic Sent and Receive: The FTP packets sent refers to the