In this letter, we analyze the identity-based signature with conditional privacy-preserving authentication scheme (short for IBS-CPPA, published in Journal of Systems Architecture, doi: 10.1016/j.sysarc.2019.101692) and demonstrate that it cannot provide secure authentication between vehicles. Specifically, in IBS-CPPA, two types of adversaries can launch different attacks to forge a valid signature on any traffic-related message to impersonate a target vehicle, so as to invalidate the authentication between vehicles.

中文翻译：

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对基于身份的VANET签名方案的评论

在这封信中，我们使用条件隐私保护的身份验证方案（IBS-CPPA的缩写，发布于Journal of Systems Architecture，doi：10.1016 / j.sysarc.2019.101692）来分析基于身份的签名，并证明它不能提供安全的身份验证车辆之间。具体而言，在IBS-CPPA中，两种类型的对手可以发起不同的攻击，以在与交通有关的任何消息上伪造有效签名，以模拟目标车辆，从而使车辆之间的身份验证无效。