A lightweight two-gateway based payment protocol ensuring accountability and unlinkable anonymity with dynamic identity

In the current scenario, mobile web payment provides a standard platform to the Internet users for online digital goods shopping. Though the majority of online transactions use single gateway, there is a need for multi-gateway, due to insufficient balance in a customer's account in a specific bank. There are a few payment protocols which support a transaction using multiple cards, but they too have some limitations like cards should be of the same bank and the process should be based on independent transactions. This paper proposes an efficient payment protocol that is used for making online transactions via two gateways for purchasing digital goods to overcome the above mentioned limitations. The proposed protocol is simulated using the automated tool Cryptographic Protocol Shape Analyzer (CPSA) and it satisfies accountability, anonymity and atomicity properties. Formal proof of correctness is provided using the strand space model. The protocol is then compared with the state-of-the-art protocols in terms of different security features and computational overhead. Results show that our protocol achieves better performance than other protocols. (C) 2016 Elsevier Ltd. All rights reserved.