AN ENHANCED APPROACH FOR CP-ABE WITH PROXY RE-ENCRYPTION IN IOT PARADIGM 10.5455/jjcit.71-1643700224 Nishant Doshi Attribute,Multi-authority,Proxy re-encryption,Constant length 117 32 1-Feb.-2022 18-Apr.-2022 27-Apr.-2022 In Internet of Things (IoT), encryption is a technique in which plaintext is converted to ciphertext into make it non-recovered by the attacker without secret key. Ciphertext policy attribute-based encryption (CP-ABE) is an encryption technique aimed at multicasting feature; i.e., user can only decrypt the message if the policy of attributes mentioned in the ciphertext is satisfied by the user’s secret key attributes. In literature, the authors have improvised the existing technique to enhance the naïve CP-ABE scheme. Recently, in 2021, Wang et al. have proposed the CP-ABE scheme with proxy re-encryption and claimed it to be efficient as compared to its predecessors. However, it follows the variable-length ciphertext in which the size of ciphertext is increased with the number of attributes. Also, it leads to computation overhead on the receiver during decryption which will be performed by the IoT devices. Thus, in this paper, we have proposed on improved scheme to provide the constant-length ciphertext with proxy re-encryption to reduce the computation and communication time. The proposed scheme is secured under Decisional Bilinear Diffie-Hellman (DBDH) problem.