Context-based BSM Aggregation for Broad-Scale Applications in Vehicular Networks

摘要

In the U.S, the Basic Safety Message (BSM), commonly known as heartbeat message, has been proposed as the primary message set used by the connected vehicles' safety applications to constantly exchange data within the vehicular ad hoc networks (VANETs). BSM is communicated around 10 times per second through Dedicated Short-Range Communications (DSRC) to be exclusively used in the safety context. Once the BSM is used, it becomes obsolete and is destroyed. Nevertheless, albeit the BSM has been primarily developed to be used in the safety context, it has a capacious field of use. Other connected vehicle non-safety applications, like efficiency, environment, weather and mobility, may also use the data in the message. A wide range of BSM data elements are required by an important bunch of non-safety applications. Leastwise, core data elements of the BSM part one if cached, grouped and sent otherwise, they can solely and adequately provide the vehicle-based information needed for broad-scale applications. In this paper, we propose an Application-Level Flextime Aggregation (ALFA) scheme, allowing BSMs to be cached on-board the vehicle, intelligently aggregated according to different contexts and then sent in new message containing stored snapshots for every stretch of roadway. These new messages could be sent to vehicles and infrastructures, via Wi-Fi, digital cellular, or over a combination of all to provide broad-scale applications with needed information. The main novelty of our ALFA scheme is its contribution to change the way active safety transportation data (BSM) is treated, making it more valued, resulting in reliable and useful data source, and an efficient transportation network scaling to large areas. After a study case relevant to the vehicles mobility, obtained results showed that ALFA enhances the BSM' usefulness and provide mobility applications with useful input data.