关键词：汽车；汽车漫游系统；密钥协议
摘 要：With the fast advance of communication technologies,there is an increasing demand of efficient operations in low-power roaming environment.Several protocols came into being successively,yet for special requirements in automobile roaming system such as low consumption,high performance and convenience,these protocols cannot achieve a proper balance between security and efficiency since these protocols pay more attention to a common network environment.In order to go out from the embarrassing situation,we commit to provide a secure and effective mutual authentication mechanism for automobile roaming scenario.Our protocol employs elliptic curve cryptography system to reduce computational and communicational cost.Moreover,we also take into account common attacks and give corresponding resist measures to ensure security.In summary,our protocol is suitable for automobile roaming scenario since it provides user's anonymity,mutual authentication and is more efficient.