Improvement on Meshram et al.ʼs ID-based cryptographic mechanism

•Analyses show that there exists a deadlock problem in Meshram et al.ʼs scheme because the user cannot decrypt the ciphertext as expected.•An improvement on Meshram et al.ʼs scheme is proposed to solve this deadlock problem.•The proposed scheme is as secure as Meshram et al.ʼs scheme, and it is more efficient than Meshram et al.ʼs scheme.

Meshram et al. proposed an ID-based cryptosystem based on the generalized discrete logarithm problem (GDLP) and the integer factorization problem (IFP) in 2012, and their contribution lies in that they firstly proposed an idea to construct the ID-based cryptosystem without using the bilinear pair. This scheme can achieve the security goal of protecting data and prevent the adversary from snooping the encrypted data or the userʼs private key. However, our analyses show that their scheme is still incorrect and has a deadlock problem, because the user cannot carry out the encryption process as expected because it is required for the user to own the key authentication centerʼs private information which is designed to be secret to users. A solution to the deadlock problem is given and an improved scheme is proposed.