Authorized Client-Side Deduplication Using CP-ABE in Cloud Storage

Table 1

Comparison of the storage overhead on the user and the CSP.

	Li et al.’ scheme [8]	Proposed scheme
User	(2h_len)	1 (ep_len ( +2)) + (1h_len)
CSP	h_len + 1ct_len + (senc_len)	1h_len + 1ct_len + 1 (ep_len ( +2)) + 1 ep_len + 1h_len

Notes.: the number of files owned and uploaded by one user; : the number of files that are uploaded by all users and managed on CSP; : the number of deduplicated file uploads; : the number of access privileges assigned to the file by the user; ct_len: the bit-length of the encrypted file; ep_len: the bit-length of the elliptic curve pairings; h_len: the bit-length of the output of the hash function; senc_len: the bit-length of the output of the symmetric encryption.