A Lightweight Authentication and Inter-Cloud Payment Protocol for Edge Computing

In this paper, we propose a lightweight mutual authentication and inter-cloud redeemable payment protocol which allows IoT devices to subscribe with their home cloud service providers for roaming coverage. More precisely, such devices acquire authenticated payment tokens in order to benefit from the computation offloading services from edge nodes deployed by foreign cloud service providers. Hence, IoT devices are continuously serviced even when outside of their home cloud providers coverage. The protocol makes use of tree of secrets, hash chains, and Merkle trees. It requires sharing a Merkle tree root and a 128-bit secret key for constructing the tree of secrets among cloud admins. Our protocol provides mutual authentication, confidentiality, and easy charge redemption from the home server. For $N$ subscribed IoT devices, the storage at the hosting clouds is limited to $2 \times (N_{s}\ +1)\times 16$ bytes and $32\times Log{N}$ bytes for the IoT device, where $N_{s}$ is the maximum number of devices served by the IoT gateway per payment redemption period.