Speech Encryption Scheme Based on Ciphertext Policy Hierarchical Attribute in Cloud Storage

Table 2

Comparison of evaluation indicators for ABE.

Evaluation index number	Reference [16]	Reference [26]	Reference [30]	Proposed
1	Type-I	Type-I	Type-I	Type-III
2	LSSS	Access tree	Access tree	LSSS
3	✓	✗	✗	✓
4	✓	✗	✓	✓
5	✗	✗	✗	✓
6	✗	✗	✗	✓
7
8

1, elliptic curve type; 2, access structure; 3, attribute coverage: large attribute universe; 4, multiuser; 5, speech encryption; 6, speech application scenarios; 7, user private key size; 8, ciphertext size.