| Protocols/Algorithms | Main Ideas |
Greedy | Geographical source routing (GSR) | Determines the destination location by RLS (reactive location service) |
Greedy perimeter geographic routing (GPCR) | The packet is greedily forwarded to the junction node (coordinator) | |
Improved greedy traffic-aware routing (GyTAR) | Selects junctions based on vehicles traffic density and distance to the destination | |
Connectivity-aware routing (CAR) | 1) Greedy forwarding between anchor points along the selected path 2)The packet is forwarded to a node closer to an anchor point | |
Opportunistic | OPERA: Opportunistic Packet Relaying in disconnected vehicular ad hoc networks | 1) Vehicles moving in the same direction are grouped into clusters 2) Opportunistic technique is used to select a better available path |
Topology-assist geo-opportunistic routing | Uses two-hop beacons for the selection of a forwarding node | |
MaxProp | 1) Uses packet priorities to maximize delivery 2) Includes three stages: neighbor discovery, data transfer, and storage management | |
Trajectory | SiFT | A data forwarder selection decision is shifted from the sender to receiver |
Geographical opportunistic routing (GeOpps) | A data forwarder is selected based on the trajectory information of individual vehicles | |
Trajectory-based data forwarding (TBD) | Is based on vehicle trajectory information and traffic statistics | |
Two-level trajectory-based routing (TTBR) | 1) The communication area is divided into cells of a grid 2) A grid based location system is applied where some peer servers are distributed |