Secure over-the-air software updates in connected vehicles: A survey

Current trends forecast that Over-the-Air (OTA) software updates will be highly significant for future connected vehicles. The OTA update will enable upgrading the vehicle functionalities or bug fixations in the embedded software installed on its Electronic Control Units (ECUs) remotely. The introduction of OTA updates in the automotive industry has brought many advantages for both the Original Equipment Manufacturer (OEM) and the driver/owner. However, in terms of security, OTA updates are highly critical as they need complete access to the in-vehicle communication network. This survey highlights and discusses OTA software updates in the automotive sector, mainly from the security perspective. The major objective of this survey is to deliver a comprehensive outline of various research directions and approaches in OTA update technologies in vehicles. At first, we discuss the connected vehicle technology and then integrate the relationship of OTA update features with the connected vehicle. We further discuss both promising and secure OTA update approaches, that have gained a lot of attention recently. Furthermore, we present a comprehensive comparative study of the existing OTA update approaches on the basis of strengths, weaknesses and evaluation setup. The survey also focuses on the existing vehicle features that support OTA updates, and customer satisfaction and usability. Finally, we identify possible future research directions of OTA updates for automobiles, particularly in the area of security.