A Framework for Efficient Multi Constraint QoS Routing in VANETs and Hybrid Network Systems

Abstract

Vehicular Ad-hoc Networks (VANETs) represent a special type of wireless network comprising of vehicles communicating among themselves. In some cases, like Intelligent Transportation Systems, such systems may connect with roadside communication units. Irrespective of the original concept that led to development of VANETs, in the contemporary context they have emerged as a class of technology that lends itself to both infrastructure-less as well as hybrid communication scenarios. Therefore, VANETs are capable of enabling smart communication services like those required in Hybrid Network Systems like Intelligent Transportation Systems (ITS), Internet-of-Things (IoT) and Smart Habitat Systems. Right from safety to traffic management, disaster time service provisioning and infotainment services, VANETs, by themselves or as parts of Hybrid Network Systems help provide varied types of time-bound, safety-critical or non-time sensitive services. A major feature of such a variety of services is that they come with varied requirements with respect to Quality-of-Service (QoS) guarantees in terms of availability, robustness and reliability. Therefore, development of strategic mechanisms and algorithms for robust, cooperative and efficient VANET communications assume paramount significance. Typically, in these services, QoS parameters of relevance could range from delay, hop-count, bandwidth, received signal strength, link lifetime to reliability and robustness. Such requirements, although leading multiple constraints, could be taken care of, to a reasonable extent by the way of smart routing. However, finding feasible paths that consider multiple QoS constraints is an NP-hard problem. Moreover, robust routing is required to be paid special attention as communication links between vehicles may frequently become unavailable or erroneous in VANETs. Furthermore, sender vehicle have to rely on other vehicles for forwarding data and therefore, cooperative communications between such nodes are required. However, due to various reaso