A survey on hybrid routing mechanisms in mobile ad hoc networks

Routing is one of the most challenging task in mobile ad hoc networks (MANETs). Several works have been proposed to address this challenge. In recent past, some of the research articles are focused on design of hybrid routing mechanisms for MANETs. In this paper, we present an overview of analytical, network, and simulation model used in the design of hybrid routing mechanisms wherever possible. This review paper classifies some of hybrid routing mechanisms into four categories named as mesh, tree, zone, and multipath structure with their relative performance. This paper also compares routing mechanisms against routing efficiency, reliability, packet delay, packet delivery ratio, control overheads, and QoS (Quality of Service). We provide an overview of most recent reliable, energy efficient, scalable, fault tolerant, and QoS based hybrid routing mechanisms and point to directions for future research and development.