Analysis and Simulation of a Predictable Routing Protocol for VANETs

Vehicular ad hoc networks (VANETs) are expected to support a large spectrum of mobile distributed applications ranging from traffic alert dissemination and dynamic route planning to context-aware advertisement and file sharing. Internetworking over VANETs becomes one of the most important applications and desired service for mobile users. In current ad-hoc routing protocols, the control messages in reactive protocols and route update timers in proactive protocols are not used to anticipate link breakage. They only indicate presence or absence of a route to a given node. Consequently, the route maintenance process at both protocol types is initiated only after a link breakage event takes place. This paper analysis the possibility to predict a link breakage event prior to its occurrence. Vehicles are grouped according to their velocity vectors. When a vehicle shifts to a different group and a route, involving the vehicle, is to be broken, the protocol searches for a more stable route that includes vehicles from the same group. Whilst this scheme (Predictable Routing Protocol - PRP) can be implemented on any existing routing protocol, the paper considers the case of PRP over Destination-Sequenced Distance Vector (DSDV) routing protocol and Optimized Link State Routing (OLSR) protocol. The performance of the scheme is evaluated through computer simulations.