Issues and Challenges in Broadcast Storm Suppression Algorithms of Vehicular Ad Hoc Networks

Vehicular Ad-Hoc Networks (VANETs) are the networks of vehicles which are characterized with high mobility and dynamic changing topology. Most of the communication interchanges in VANETs take place in broadcasting mode, which is supposed to be the simplest way to disseminate (spread) emergency messages all over the vehicular network. This broadcasting technique assures the optimal delivery of emergency messages all over the VANET. However, it also results in unwanted flooding of messages which causes severe contention and collisions in VANETs leading to Broadcast Storm Problem (BSP) and in turn affects the overall performance of VANETs. A Multitude of research work have proposed Broadcast Storm Suppression Algorithms (BSSA) to control this Broadcast Storm. These mechanisms tried to control BSP by either reducing the number of rebroadcasting/ relaying nodes or by identifying the best relay node. The suppression mechanisms help to overcome BSP to certain extent, still there is need to still reduce the number of rebroadcasting nodes in existing mechanisms and also to identify the best possible rebroadcasting node. This would help to mitigate BSP completely and efficiently. This paper presents a comparative analysis of various prominent BSSA in order to identify the underlying issues and challenges in controlling BSP completely. The outcome of this paper would provide the requirements for developing an efficient BSSA overcoming the identified issues and challenges.