This paper proposes an adaptive vehicular MAC protocol, called A-VeMAC, for VANETs. A-VeMAC is a multichannel MAC protocol based on VeMAC. Like VeMAC, it employs a TDMA mechanism, and supports one control channel and several service channels. For the control channel, each frame is partitioned into two disjoint sets of timeslots, which are associated with vehicles moving in opposite directions, respectively. Unlike VeMAC, which equally partitions each.frame, the frame partitioning with A-VeMAC is
