  A mobile ad hoc network (MANET) is a non-centralised, multihop, wireless
network that lacks a common infrastructure and hence it needs
self-organisation. The biggest challenge in MANETs is to find a path between
communicating nodes, which is the MANET routing problem. Biology-inspired
techniques such as ant colony optimisation (ACO) which have proven to be very
adaptable in other problem domains, have been applied to the MANET routing
problem as it forms a good fit to the problem. The general characteristics of
these biological systems, which include their capability for self-organisation,
self-healing and local decision making, make them suitable for routing in
MANETs. In this paper, we discuss a few ACO based protocols, namely AntNet,
hybrid ACO (AntHocNet), ACO based routing algorithm (ARA), imProved ant colony
optimisation routing algorithm for mobile ad hoc NETworks (PACONET), ACO based
on demand distance vector (Ant-AODV) and ACO based dynamic source routing
(Ant-DSR), and determine their performance in terms of quality of service (QoS)
parameters, such as end-to-end delay and packet delivery ratio, using Network
Simulator 2 (NS2). We also compare them with well known protocols, ad hoc on
demand distance vector (AODV) and dynamic source routing (DSR), based on the
random waypoint mobility model. The simulation results show how this
biology-inspired approach helps in improving QoS parameters.
