Optimistic Fair Exchange in Cloud-Assisted Cyber-Physical Systems

Table 1

Summary of fair exchange schemes.

	Identity-based cryptosystem	Semitrusted third party	Strong security
Zhang et al. [5]	No	No	No
Zhang et al. [6]	No	Yes	Yes
Fan et al. [7]	No	No	No
Kp and Lysyanskaya [8]	No	No	Yes
Gu et al. [9]	Yes	No	No
Zhang et al. [10]	Yes	No	No
Ours	Yes	Yes	Yes