  This paper evaluates the performance of the two ETSI non-area forwarding
algorithms in the GeoNetworking specification: Greedy Forwarding and Non-Area
Contention-Based Forwarding (CBF). Non-area forwarding occurs when a packet is
sent to a geographical Destination Area from a node located outside of this
area, e.g., when a vehicle wants to alert of hazardous events to other vehicles
located in a distant geographical area. The evaluation has been carried out
both in urban and highway scenarios and takes into account the complete ETSI
Architecture, including the interaction with the Decentralized Congestion
Control (DCC) mechanism. We have also compared ETSI-defined mechanisms with
optimizations found in the literature. Our main findings are that Greedy
Forwarding, when combined with DCC, is extremely ineffective even with
optimizations, and Non-Area CBFs (both ETSI CBF and an optimized version called
S-FoT+) outperform Greedy Forwarding both in highway and urban scenarios.
