MSYM: A multichannel communication system for android devices

Conventional mobile communication systems often use one single channel for data transmission, i.e., mobile devices use cellular network to transfer multimedia information. However, if attackers successfully hijack the single transmission channel, they can recover the communicated data. Focused on this issue, we introduce a Multichannel Communication System (MSYM), which aims to improve the data communication security for Android devices. The key idea of our approach is to leverage the diversity of communication mechanisms (e.g., Wi-Fi/cellular network, Bluetooth, and SMS) for transferring sensitive data in a secure way. More specifically, we use the VpnService interface provided by the Android platform to intercept the network data delivered by a sender program. Then, we split the network data into different fragments and improve the security by disordering and encrypting them via multiple transmission channels. When the target Android device receives the data fragments from different channels, it can decrypt and reorder them to reassemble the original data. In the end, we reuse the VpnService interface to inject the network data into the receiver program. Our approach can be deployed in Android devices to secure communication without the need of modifying the communication programs. In the evaluation, as a proof of concept, we implemented our approach on Android system. The experimental results show that our prototype system can secure data transmission with moderate performance cost.