The objective of this textbook is to improve Quality of Service (QoS) parameters for Multimedia Traffic using Ant Colony Optimization (ACO) based Optimized Link State Routing Protocol (OLSR) in a Mobile Ad hoc Network (MANET). The performance of proactive OLSR is evaluated for multimedia traffic and compared with Ad hoc On Demand Distance Vector (AODV) Routing Protocol. Hybridization of ACO OLSR is implemented to overcome the local minima problem of ACO and to improve the local search using novel fitness function.Simulations for hybrid ACO OLSR are carried out and compared with ACO OLSR and OLSR in terms of the average packet delivery ratio, average end-to-end delay, jitter and number of Multi Point Relays (MPR) formed for various network sizes.