Other
techniques also propose to efficiently combine the information
generated by multiple vehicles using digital road maps. For
example, in SOTIS [3], vehicles generate and exchange traffic
information about the road segment they are currently located
in, and other road segments for which they have traffic
information. This information can be generated by the vehicles
themselves or received from other vehicles. To avoid the
communications overload that could be generated by
neighboring vehicles, [3] additionally proposes the use of an
adaptive broadcast algorithm. Differently from SOTIS, in [4],
only a single vehicle in each road segment is in charge of
collecting and aggregating road traffic data. Once aggregated,
the information is transmitted to adjacent road segments.