Vehicle-to-vehicle

Vehicle-to-vehicle (V2V) is an automobile technology designed to allow automobiles to "talk" to each other. V2V communications form a wireless ad hoc network on the roads. Such networks are also referred to as vehicular ad hoc networks, VANETs. The systems will use a region of the 5.9 GHz band set aside by the United States Congress, the unlicensed frequency also used by WiFi. The US V2V standard, commonly known as WAVE ("Wireless Access for Vehicular Environments"), builds upon the lower-level IEEE 802.11p standard, as early as 2004.

For Europe Commission Decision 2008/671/EC harmonises the use of the 5 875-5 905 MHz frequency band for transport safety ITS applications. In Europe V2V is standardised as ETSI ITS-G5, a standard also based on IEEE 802.11p. C-ITS, cooperative ITS, is also a term used in EU policy making, closely linked to ITS-G5 and V2V.

V2V is also known as VANET (vehicular ad hoc network). It is a variation of MANET (Mobile ad hoc network), with the emphasis being now the node is the vehicle. In 2001, it was mentioned in a publication that ad hoc networks can be formed by cars and such networks can help overcome blind spots, avoid accidents, etc. The infrastructure also participates in such systems, then referred to as V2X (vehicle-to-everything). Over the years, there have been considerable research and projects in this area, applying VANETs for a variety of applications, ranging from safety to navigation and law enforcement.

In 1999 the US Federal Communications Commission (FCC) allocated 75 MHz in the spectrum of 5.850-5.925 GHz for intelligent transport systems.

As of 2016, V2V is under threat from cable television and other tech firms that want to take away a big chunk of the radio spectrum currently reserved for it and use those frequencies for high-speed internet service. V2V's current share of spectrum was set aside by the government in 1999. The auto industry is trying to retain all it can saying that it desperately needs the spectrum for V2V. The Federal Communications Commission has taken the side of the tech companies with the National Traffic Safety Board supporting the position of the auto industry. Internet service providers who want the spectrum claim that self-driving cars will make extensive use of V2V unnecessary. The auto industry said it is willing to share the spectrum if V2V service is not slowed or disrupted; the FCC plans to test several sharing schemes.

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Wikipedia