Performance evaluation of a mixed vehicular network with CAM-DCC and LIMERIC vehicles

Channel congestion is one of the major challenges for IEEE 802.11p-based vehicular ad hoc networks. Facing the challenge, several algorithms have been proposed. Two good representatives are the Decentralized Congestion Control (DCC) framework defined by ETSI and LIMERIC, a linear control algorithm. Both algorithms control message transmission rate as a function of channel load (i.e., channel busy percentage, CBP). In this work, DCC is assumed to be deployed for day one applications and LIMERIC is introduced into the network afterwards. Given such a mixed vehicular network with vehicles running either DCC or LIMERIC, we evaluate the performance of the two algorithms in the mixed scenario and study the impact of such mixed network operation on the performance through ns-2 simulations. It is observed that converting some CAM-DCC vehicles to LIMERIC vehicles will not lead to any significant performance degradation of either CAM-DCC or LIMERIC vehicles. Any observed performance degradation is small enough so that we would expect typical DSRC applications to still be feasible. Performance differences between DCC and LIMERIC exist but they can be reduced through careful selection of the specific parameters of LIMERIC and DCC, respectively.