Cellular, Security Challenge Vehicle-to-Vehicle’s Role

Telematics links provide many of the benefits of V2V that government regulators are now mandating, while security issues pose major technical challenges, with secure communications a key hurdle for V2V’s rollout.

October 1, 2015

Terry Costlow

Toyota’s already selling V2X systems in Japan, communicating with stoplights and other vehicles to improve safety.

Safety proponents are looking forward to the day when cars can send each other information that can prevent accidents. But cellular technologies may eliminate some benefits of vehicle-to-vehicle communications, while difficult security concerns require a complex, long-term strategy.

In 2017, the Cadillac CTS (2015 model shown) will be the first U.S. car to come with a V2X link.

Vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications use dedicated short range communications (DSRC) to provide information on vehicle speed and location. Commonly lumped together as V2X, the technologies can play a major role in reducing accidents. Government regulators in the U.S. and Europe are expected to mandate their use before long. In Japan, shipments are beginning to build, giving the industry a working model.

“We’ll be selling V2V this year, and we’ve been selling V2I for around four years,” said Hideki Hada of Toyota Motor Engineering & Manufacturing’s Integrated Vehicle Systems Dept. “In Japan, the applications are similar to the U.S., but the frequencies are different. The only things we need to change for the U.S. are the radio chip and the antenna.”

There are solid reasons for the interest. The U.S. National Highway Traffic Safety Administration (NHTSA) found that V2X could help reduce the occurrence and severity of 22 of the 37 types of crashes defined in a study. That could improve safety more than many of the agency’s previous efforts.

Cellular links can bring most of the benefits of V2X without adding any cost, said Volvo’s Coelingh.

“That’s around 80% of all crashes,” said John Capp, Director, Global Vehicle Safety at General Motors. “If you add up all the work done on seatbelts and airbags, it wouldn’t match the benefits we could get from V2X.”

However, that impact could be some years coming. If a firm mandate comes, it will take years to build a critical mass of vehicles that can communicate with each other.

GM highlighted its support of DSRC by announcing that the 2017 Cadillac CTS will have V2V capabilities. While Cadillac owners won’t gain many benefits by talking to each other, GM feels that its strategy will bring a solid amount of knowledge with a small downside. If NHTSA sets a regulation that isn’t fully compatible, changes will probably be minimal.

“We think the standards are ready,” Capp said. “It’s a bit of a risk, but we have ideas to handle that risk. If we have to reflash some vehicles, it’s not a major challenge. The main thing that’s still an issue is security.”

Is cellular smart enough?

DSRC has low latency, which is critical for safety-related communications. (Source: Ford)

Until government mandates kick in, automakers are using onboard telematics links to provide many of the features DSRC could provide. Signals sent to the cloud can give drivers road conditions and other information.

“Using the Cloud and the 3G and 4G links that are already there bring most of the benefits of V2V,” said Erik Coelingh, Senior Technical Leader, Safety Electronics & Functions at Volvo. “When roads are slippery, cars can send data to the Cloud to create a map that can be transmitted to cars in the area. When there’s an accident, calls to emergency services could be shared, as could information about a stalled vehicle on the roadway.”

Many tasks such as providing traffic warnings that were once seen as a way to amortize DSRC’s costs are no longer valid. The ubiquity of high bandwidth connected car links makes them viable for many of those chores.

“If DSRC had come out 10 years ago, it might have been the way to provide firmware updates,” said Andrew Poliak, Global Director, Business Development for QNX Software Systems. “It’s taken so long to roll it out that other alternatives have emerged.”

However, sending signals to cell towers and getting info back to vehicles introduces latency. Safety alerts can’t tolerate those delays.

“DSRC provides low latency and high availability, which you need to send basic safety messages for things like speed, position, and heading,” said Mike Shulman, Ford’s Global Driver Assistance and Active Safety Manager.

There’s some talk about next-generation 5G cellular techniques, which could reduce latencies to acceptable levels for safety, as a replacement for DSRC. However, a time frame for rollouts is uncertain, so coverage could be quite spotty for years. Additionally, shifting to 5G technology would require substantial testing and development work that’s already been done for V2X.

“It takes a while to get the states moving; there’s some momentum there now,” Capp said. “If you reset the clock to change frequencies or technologies or alter the rules, it will delay the safety benefits that this brings.”

Serious about security

Security is a critical factor for communications modules throughout the vehicle’s lifetime, including maintenance, QNX Systems’ Poliak noted.

Secure communications is a key hurdle for V2V’s rollout. The auto industry’s concerns go beyond those faced by conventional cybersecurity programs. Protecting vehicles begins at the initial rollout and runs until end of life. Aftermarket suppliers may also become involved.

“The aftermarket may be the best way to gain the benefits without waiting years until most vehicles have V2V,” said Andy Whydell, Product Planning, TRW Electronics. “Security will be a challenge, depending on how much information aftermarket systems need to get from the vehicle. It’s unclear how much OEMs will want to provide to aftermarket equipment that they haven’t tested. Given all the cybersecurity concerns, OEMs may not want to provide information when they’re not sure what aftermarket equipment may do, intentionally or unintentionally.”

Manufacturers of the V2X modules will have to protect them when security information is programmed into boxes. Encryption technologies in these modules will play an important role in keeping hackers from spoofing or stealing messages.

“Modules will require certification; the operating system will be one of the building blocks needed to build a safe system,” Poliak said. “There must also be strategies for certificate management and plans to issue key pairs as well as other things needed to manage modules.”

The sheer size of the network will be daunting if most vehicles eventually have V2X links. There won’t be much time for vehicles to determine whether they’re communicating with a certified module or a bad actor.

“When a vehicle meets a vehicle it’s never seen before, how do you manage trust so the vehicles both know messages are valid,” Shulman said. “With over 200 million vehicles in the U.S., V2V would be the largest public key infrastructure system ever deployed.”

Security remains an issue over time as vehicles need maintenance. Encryption keys and certificates must be protected even if V2X modules are repaired or replaced.

“There are some challenging security concepts,” Poliak said. “There will be trade-offs between security strategies and laws that require that people can work on vehicles. You have to balance that right-to-work on a car versus the need to protect security modules.”

If V2X is indeed mandated, NHTSA will play a critical role in creating the security infrastructure for this safety technology. At this early stage, the agency’s role remains uncertain. Some observers feel regulators will work with a third party that administrates protective schemes.

“One model is that NHTSA will specify technologies, then give the business of running the security systems to a third party, with NHTSA retaining some oversight,” Capp said.