2022-03-What is vehicle-to-vehicle communications (V2V) and how does it work

What is vehicle-to-vehicle communications (V2V) and how does it work?

Image Credit: Wikimedia Commons


Did you know that vehicle to vehicle communication is possible? And no, vehicle to vehicle communication doesn’t involve rolling your window down, shouting between cars, or using a variety of hand or finger gestures. Electronics based vehicle to vehicle communications offer a way to make driving safer with fewer crashes. This article explores the concept behind “V2V communications” as well as the history of vehicle communications, safety and security implications, and the future of V2V. Let’s begin with the history of vehicle communications and what led to today.


Attempts to make vehicles communicate with one another via a wireless network have been in the works for at least a decade. As of 2014, the government’s traffic organization, the National Highway Traffic Safety Administration has started to consider requiring passenger vehicles to include a wireless communication system. As of 2016, the NHTSA will start proposing rules that auto manufacturers will have to build within their vehicles. The rules will be created following a three-month comment period in which the NHSTA can gather information about what is important in creating these rules.

2022-03-What is vehicle-to-vehicle communications (V2V) and how does it work

Image Credit: Wikimedia Commons

Dedicated Communications

Previously, the Federal Communications Commission set aside the specific 5.9GHZ band for vehicle-to-vehicle communication in 1999. The band is no longer likely to be used for the purpose as more recent developments in 5G communication have taken over.

While the NHTSA and FCS stepping in are a start to making V2V more available in vehicles, one of their roles will be to bring automakers together to come up with a standard for communications so that an Audi, Chevrolet, Ford, and Tesla can all communicate.

Back to the 1970s

Concepts regarding vehicle communication reach all the way back to the 1970s. The United States, parts of Europe, and Japan tested out systems that included the Electronic Route Guidance System. These systems included the ability to help vehicles navigate on the road, but not directly with one another.1

What is Vehicle to Vehicle communication?

Vehicle to vehicle communication uses a combination of sensors and wireless technology to allow communication between vehicles to prevent crashes. Up to 90% of all traffic accidents are caused by driver errors and poor decision making.

Very simple, sensors within the vehicle detect the driver’s rate of speed, position via a GPS, and acceleration, amongst other data points to all cars within about 250 meters. Other vehicles with V2V built in could receive and interpret these signals, then when needed, create warnings and actions for drivers based on the information being received.

A Traveling Network

V2V would produce a traveling wireless network on its own. While the GPS communication systems in your car rely on external satellites and outside technology, V2V would work based on creating a network with cars as they are traveling without the need for outside satellites. Rather than just having one vehicle speak to one satellite in space, this system is on ground and has your vehicle detecting and communicating with every vehicle nearby. 2

One could call the network created by traveling cars a “mesh” network. This means that the network is produced by the cars and is highly adaptable and changes constantly to allow vehicles to communicate with those who are in the immediate area. A mesh network is similar to the one used in a large home that might have multiple Internet access points that create a wireless network rather than having one access point. The advantage? Devices and cars can come and go as they please without impacting the network communications.

Vehicle to vehicle communication is not quite self-driving - yet

With manufacturers like Tesla attempting to gradually introducing self-driving cars, the average person reading the news has probably heard about potential benefits and issue of self-driving abilities. Self-driving cars are coming, now, within subscription models. Vehicle to vehicle communication is not quite the same thing, though. A self-driving car can literally navigate you to a place. The vehicle can turn, accelerate, brake, and signal by itself while finding its way across your streets to the destination.

Managing safety moments

Vehicle to vehicle communication is more focused on the small moments between starting and your vehicle and getting there. This includes making lane changes and knowing about potential dangers and issues that the user couldn’t see. A person who is driving their vehicle and doesn’t see another driver blow through a red light would benefit from a warning about incoming danger. In the case of what the NHTSA is trying to push forward, the driver would know about a problem, but the vehicle itself would only communicate the issue to both vehicles without actively taking over driving.

For people who like actively driving and having control of their vehicle, this can come as good news. Some drivers prefer the need to steer, brake, and accelerate on their own without computer direction, and V2V won’t necessarily take that away.

Safety Benefits

While self-driving cars are an eventual goal, the safety benefits of vehicle-to-vehicle communications are amongst the basic needs of everyday drivers.

Amongst the leading causes of accidents are distracted driving, speeding, drunk driving, fatigue, and weather. While V2V communications cannot actively stop all of these, it can certainly help communicate the potentially dangerous movements a driver makes while they fall asleep at the wheel. A driver who is actively using their cell phone while driving could send out information to nearby vehicles that they are accidentally switching lanes or approaching a stopped car while driving too quickly.

Distracted driver related problems have also resulted in the introduction of laws against anything but hands-free use. These laws and their enforcement have led to a significant reduction in distracted driver crashes. 3 Distracted driver problems could be further reduced by having vehicles communicate back and forth about what’s happening.

Consider the history of the vehicle and the introduction of better steel safety cages and seatbelts. Better safety structures and devices were designed to make it more possible to survive a crash. Then came safety features like blind spot alert and pedestrian detection, which helped reduce the chances of a crash without communicating to anyone else. Consider vehicle to vehicle communication the next step in having vehicles cooperate to avoid crashes. You already have a vehicle that is safer than ever, now you can reduce your chances of needing to test your vehicle safety abilities.

What V2V could track and report

Your vehicle already has many sensors dedicated to helping the vehicle adjust to conditions. These conditions changes could be shared with organizations interested in safety, for the purpose of changing traffic infrastructure and vehicles to make them easier to use.

Was the traction control enabled due to slick or slippery road conditions? Was the driver signaling to change lanes? Can one vehicle report that the other was outside of their lane? All of these things could help pinpoint problems. Vehicles communicating within a football field's length that everyone is slamming on their brakes could help overseers know of a potential hazard, like a stalled vehicle or something in the roadway.

Big brother concerns

Concerns about data privacy have been present since people started using GPS and other devices. The Electronic Frontier Foundation has some valid concerns about privacy within the communications a vehicle sends out and how they could be used, in addition to the validity of messages.

The EFF fears that the communication system could readily either result in hacking with untrusted messages, or unnecessary tracking. While the NHTSA says they plan to offer 20 secure certificates per week to a car to verify a trusted identity, these certificates could also be used to track the location of vehicles by someone with the computer ability to do so. While license plate readers do exist, the government and other actors could readily gain the ability to track a vehicle without needing to see the license plate first.

The method of messaging used by the proposed NHTSA rules is also in question by the EFF. While the government could use their security certificates to establish the trust of a public service message, the EFF says the systems proposed by the NHTSA can’t determine if the message itself is trustworthy. The system could then be used on accident or purposefully to communicate bad information and put people in danger.

Who gets the information?

On a less specific level, there are concerns about who has access to where specific vehicles go. Do car manufacturers get to know where their vehicles go? Who has access to the information regarding location whereabouts or even driving histories? Is law enforcement allowed to identify either a vehicle or a driver?

What do vehicle to vehicle communication advocates say about privacy?

EFF does have valid concerns about the ability to track a vehicle. The NYC Connected Vehicle program claims that the V2V system doesn’t store any personally identifying information about the driver of a vehicle. They also claim the ability to track a vehicle might be overblown and very difficult for the average person to do. 4

One of the largest issues between vehicle manufacturers and the NHTSA is that manufacturers like Tesla, Ford, and Volkswagen don’t believe the NHTSA is yet capable of fully protecting privacy.5 These companies often have their own ways of protecting data privacy while providing a service that collects the data.

Will Vehicle to Vehicle communications help bikers and pedestrians?

Not yet. In a roundabout way, vehicle to vehicle communications could help vehicles avoid accidents with one another when the lead car stops quickly to avoid a biker or pedestrian. The limitation here is that the communication is coming from the vehicle and not the person.

Vehicle to pedestrian communication, known as V2P, is the next step is protecting the lives of pedestrians and bikers. Almost 20% of traffic related deaths of last year’s 30,000 were the result of a vehicle striking a biker or a walker - or someone outside of a vehicle. 6

Lowering the risk for pedestrians offers a different set of challenges than vehicle to vehicle communication. A computer can be built into the vehicle to process communications and send warnings. Manufacturers do build vehicles with some options including pedestrian detection and automatic braking to avoid collisions with people, which is a start.

The Department of Transportation currently focuses on developing systems that help people who have either vision disabilities or mobility concerns. The DOT wants these people to be able to use a phone app or phone call to start a system that will warn oncoming drivers that someone will be in the crosswalk. A separate system that warns bus drivers about people within a crosswalk is in the works too.

The next hope is that the DOT finds a way to send imminent messages to people’s handheld devices regarding a danger, though the technology isn’t there yet. Delays in sending would be substantial, privacy issues abound, and people are unlikely to react to a new message in time to make it worthwhile.

Will Vehicle to Vehicle communication cost more?

While there isn’t much to any information about the price of dedicated lanes for V2V communications, manufacturers have indicated installing a V2V system on a vehicle should cost around $350.7 Car buyers will likely bear the brunt of the additional expense, as government safety regulations have added over $2000 to the MSRP of new vehicles in recent years. Auto manufacturers now need to meet almost 40 safety requirements, not including those potentially included with V2V.8

Given the presence of toll lanes that enable more efficient driving during traffic slowdowns, it is possible to see a monthly fee for a V2V lane.

How many V2Vs are needed to make an impact?

One of the biggest issues with using V2V communication to make readers safer is the need to have an overwhelming number of vehicles use it and communicate. With the NHTSA not yet making systems required, it will be a considerable investment in time and money to receive the full benefit of a V2V system.

While the NHTSA can legally require manufacturers put V2V systems in new cars, people will still buy used cars that don’t have systems built in yet, and those cars won’t communicate.

Vehicle manufacturers are among the largest influencers on the ability to mass manufacture V2V vehicles. They offer mixed support, with Toyota amongst others pointing out that billions have already been spent furthering V2V safety with no significant impact yet.

The largest challenges to widespread V2V use will be having the NHTSA establish a single system that all manufacturers follow, with safe, fast communication for drivers.9

The number of vehicles needed to create a good V2V network is truly unknown. The best bet is to hope for auto manufacturer cooperation to make the technology more prevalent on newly sold cars. The newly sold cars will then trickle to used car buyers and potentially make a more extensive network of V2V vehicles. Realistically, proper vehicle to vehicle communication is at least a decade away, depending in part on the involvement of the government and auto manufacturers.

Final thoughts

Vehicles have a long way to go before vehicle-to-vehicle communications are an effective way to keep vehicles out of accidents. Auto manufacturers and governing bodies will need to come to agreements as to how to implement V2V so that as many vehicles offer the benefits of communication as possible.

Vehicle safety has also come a long way since the 20th century. When vehicles first hit the road, safety belts and true safety cages weren’t common. Safety belts are now in every vehicle, and we can use radar-based guidance to both alert drivers and attempt to stop vehicles before collisions. We can for now hope that the NHTSA makes progress on a good standard for all auto manufacturers to use, while keeping systems affordable and accessible.