Pervasive service access with SIM-based VPN

Mobile users need to have access to internal resources on their enterprise or home network from remote locations in an efficient but secure way. Currently, such a secured access is realised with Virtual Private Network (VPN) connections. Although operational, the current VPN solutions suffer of severe limitations. Most of the VPN solutions are not sufficiently secured since they are using weak authentication. The more secured ones are quite often expensive and require the usage of security tokens that demand administration from the service provider. On the user´s side there is a need for additional care and attention since he/she has to carry an extra device. This paper presents a VPN solution that remedies the mentioned limitations by re-using an existing device, namely the mobile phone and its SIM card as a security token. Another ingenuity of the solution lies on the separation of the authentication phase from the rest of the VPN establishment process making possible the usage of the same security token for multiple VPNs. The solution is hence secured, affordable and practical for the users.