关键词: 车联网, 群组密钥, 密钥树, 轻量级, 加密认证

Abstract: Based on the characteristics of the Internet of vehicles(IoV), a treebased lightweight group key management mechanism (Lightweight Tree Group Key Management Mechanism, LTGKM) is proposed to realize the security of multicast and broadcast communications in the IoV. LTGKM adopts a hierarchical approach to generate, distribute and update the group keys. The management node of various layers generates the corresponding group key using the HMAC function as the key derivation function, and distributes the group key to the child node based on the encrypted certification algorithm; When a new node joins, the parent node generates a new group key and distribute it to the new node, and the remaining nodes update the group key by themselves; when the user leaves, the nonleaf node updates the group key by themselves, and the new group key is distributed to the leaf node by its father node. Security analysis shows that LTGKM realizes the randomness, forward security, and backward security during the group key generation and update, and the confidentiality, integrity and uniformity during key distribution. Performance analysis shows that LTGKM has obvious advantages in storage, computing and communication.

Key words: Internet of vehicles, group key, key tree, lightweight, encryption authentication