An approach to enhance inter-provider roaming through secret sharing and its application to WLANs

In this paper, we show how secret sharing can be used to address a number of shortcomings in state-of-the-art public-key-based inter-provider roaming. In particular, the new concept does not require costly operations for certificate validation by the mobile device. It furthermore eliminates the need for a secure channel between providers upon roaming. We demonstrate the new approach by introducing a new protocol, EAP-TLS-KS, for roaming between 802.11i-protected WLANs. In addition, we show that the properties of EAP-TLS-KS allow for an efficient integration of a micropayment scheme.