Research Article
Cryptanalysis of an Efficient and Secure Certificateless Aggregate Signature-Based Authentication Scheme for Vehicular Ad Hoc Networks
Table 4
Comparison of communication overhead.
| Scheme | Single signature length | Aggregate signature length | Coalition attack | Types I and II attacks |
| Kumar et al. [4] | = 2048 bits | bits | No | Yes | Mei et al. [13] | = 2048 bits | = 2048 bits | No | Yes | Xu et al. [14] | = 2048 bits | bits | No | Yes | Thumbur et al. [18] | = 480 bits | = 320n + 160 bits | No | No | Our scheme | = 480 bits | = 320n + 160 bits | Yes | Yes |
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Note. n: the number of messages.
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