The use of e-payment system for electronic trade is on its way to make daily life more easy and convenient ‎ .  ‎ Contrarily ‎ ,  ‎ there are a number of security issues to be addressed ‎ ,  ‎ user anonymity and fair exchange have become important concerns along with authentication ‎ ,  ‎ confidentiality ‎ ,  ‎ integrity and non-repudiation ‎ .  ‎ In a number of existing e-payment schemes ‎ ,  ‎ the customer pays for the product before acquiring it ‎ .  ‎ Furthermore ‎ ,  ‎ many such schemes require very high computation and communication costs ‎ .  ‎ To address such issues recently Yang et.al ‎ .  ‎ proposed an authenticated encryption scheme and an e-payment scheme based on their authenticated encryption ‎ .  ‎ They excluded the need of digital signatures for authentication ‎ ,  ‎ further they claimed their schemes to resist replay ‎ ,  ‎ man-in-middle ‎ ,  ‎ impersonation and identity theft attack ‎ ,  ‎ while providing confidentiality ‎ ,  ‎ authenticity ‎ ,  ‎ integrity and privacy protection ‎ .  ‎ However our analysis exposed that Yang et al.'s both authenticated encryption scheme and e-payment system are vulnerable to impersonation attack ‎ .  ‎ An adversary just having knowledge of public parameters can easily masquerade as a legal user ‎ .  ‎ Furthermore ‎ ,  ‎ we proposed improved authenticated encryption and e-payment schemes to overcome weaknesses of Yang et al.'s schemes ‎ .  ‎ We prove the security of our schemes using automated tool ProVerif ‎ .  ‎ The improved schemes are more robust and more lightweight than Yang et al.'s schemes which is evident from security and performance analysis ‎ .  DOI:  http://dx.doi.org/10.5755/j01.itc.44.4.9197
['Mohammad Heydari', 'S. Mohammad-Sajad Sadough', 'Shehzad Ashraf Chaudhry', 'Mohammad Sabzinejad Farash', 'Mohammad Reza Aref']
An Improved Authentication Scheme for Electronic Payment Systems in Global Mobility Networks