The wireless communication with delivering variety of services to users is growing rapidly in recent years. The third generation of cellular networks (3G), and local wireless networks (WLAN) are the two widely used technologies in wireless networks. 3G networks have the capability of covering a vast area; while, WLAN networks provide higher transmission rates with less coverage. Since the two networks have complementary properties, some attempts are made for their integration which could lead to an advantageous heterogeneous network. In such a heterogeneous network, provision of services like authentication, billing and quality of service are essential. In this article, a new mutual authentication protocol, namely, Non-Reputation Billing Protocol (NRBP) is proposed based on extensible authentication protocols. This authentication scheme provides a non-repudiation property for the billing problem. The proposed scheme is analyzed based on different security features and computation overhead. In comparison with previous approaches, this protocol contains all the considered security parameters. Moreover, the computation overhead of this protocol is less than other schemes.
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