From multipoint relaying to chain-branch-leaf: Improving the clustering in OLSR for vehicular ad hoc networks

The Optimized Link State Routing (OLSR) protocol, early designed for Mobile Ad hoc Networks (MANET), has been customized and evaluated for various Vehicular Ad hoc Network (VANET) scenarios. Most of the related work focus on changing OLSR parameters in order to adapt it to the high dynamicity of VANET due to high velocity of its nodes. However, they keep using OLSR with its native clustering scheme, the Multipoint Relaying (MPR). Recently, the chain-branch-leaf (CBL) clustering scheme has been proposed for road traffic configuration. This work presents a comparative analysis of CBL with MPR clustering in OLSR. The results show that CBL reduces significantly the routing traffic overhead in OLSR by reducing the number of relays, without degrading the performance for the application traffic.