SPOC: Secure Payments for Outsourced Computations

TL;DR

SPOC is a secure, decentralized payment system for edge computing in IoT networks that ensures proper task execution and result verification without third parties, using blockchain and trusted hardware.

Contribution

The paper introduces SPOC, a novel secure payment system enabling trustless, verifiable outsourcing of computations at the edge using smart contracts and hardware enclaves.

Findings

Proven security against malicious nodes

Low operational costs demonstrated in evaluation

Effective enforcement of proper user behavior

Abstract

Constrained devices in IoT networks often require to outsource resource-heavy computations or data processing tasks. Currently, most of those jobs are done in the centralised cloud. However, with rapidly increasing number of devices and amount of produced data, edge computing represents a much more efficient solution decreasing the cost, the delay and improves users' privacy. To enable wide deployment of execution nodes at the edge, the requesting devices require a way to pay for submitted tasks. We present SPOC - a secure payment system for networks where nodes distrust each other. SPOC allows any node to execute tasks, includes result verification and enforce users' proper behaviour without 3rd parties, replication or costly proof of computations. We implement our system using Ethereum Smart Contracts and Intel SGX and present first evaluation proving its security and low usage cost.