B-SSMD: A Fine-Grained Secure Sharing Scheme of Medical Data Based on Blockchain

Table 6

Scheme comparison.

Scheme	Mainchain pressure	Blockchain structure	Security	Division granularity	Encryption mode
Liu et al. [21]	++	Single	+	−	Public key
Cao et al. [32]	+	Hybrid double	−	−	Hash
Malamas et al. [34]	−	Hierarchical	+	+	CP-ABE
Proposed scheme	−	Hybrid three	++	++	Three-layer