Attribute Based Broadcast Encryption with Short Ciphertext and Decryption Key

Abstract

Attribute Based Broadcast Encryption (ABBE) is a combination of Attribute Based Encryption (ABE) and Broadcast Encryption (BE). It allows a broadcaster (or encrypter) to broadcast an encrypted message that can only be decrypted by the receivers who are within a predefined user set and satisfy the access policy specified by the broadcaster. Compared with normal ABE, ABBE allows direct revocation, which is important in many real-time broadcasting applications such as Pay TV. In this paper, we propose two novel ABBE schemes that have distinguishing features: the first scheme is key-policy based and has short ciphertext and constant size decryption key; and the second one is ciphertext-policy based and has constant size ciphertext and short decryption key. Both of our schemes allow access policies to be expressed using AND-gate with positive, negative, and wildcard symbols, and are proven secure under the Decision n-BDHE assumption without random oracles.

Attribute‐based broadcast encryption scheme for lightweight devices

“…in [15], the extension of Boneh‐Gentry‐Waters (BGW) technique to ABBE setting makes the secret key longer, due to the obligation of combining different attributes in the decryption, as shown in [7]. The problem of designing constant‐size private key ABBE schemes supporting fine‐grained access control was partially solved in ESORICS ‘15 [16]. However, the problem is still open since the proposed non‐monotonic scheme only manages restrictive access policies supporting AND‐gates and wildcards: they do not treat the case of CNF or DNF forms.…”

“…Overall, even though extensively studied in the recent years with many ABBE schemes have been proposed [7, 14, 16, 24–28] to name a few, and one of the challenges is to design a CP ‐ABBE scheme which achieves simultaneously the constant‐size secret key, efficient ciphertext size, fine‐grained access policy and fast decryption.…”

“…The notion of ABBE has then been introduced in [14] to address the problem of user revocation. The case of ABBE is more recent but has been considered in many papers such as [7, 14, 16, 24–28].…”

“…1 a detailed comparison among our scheme and several other CP ‐ABE and CP ‐ABBE schemes. We also give an implementation comparison between our scheme and the CP ‐ABBE scheme at ESORICS ‘15 [16] in Section 5.…”

Fully secure non-monotonic access structure CP-ABE scheme

“…This scheme is restricted therein it allows an authority merely to issue private keys expressing threshold policies. Since then, several works [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] proposed different ABE systems and applications, among which two worksare remarkable. Goyal et al [6] propounded a fine-grained access constraint for attribute-based encryption.…”