EchoLink is a blockchain oracle deployed on the Solana designed for DePIN IoT devices. It bridges and extends a variety of IoT devices, collecting, measuring, and verifying their workload through a unique proof mechanism to generate credible data reports. This data is encrypted with Zero-Knowledge Proof and sent to oracle nodes, which evaluate the rewards that can be earned by each device unit. EchoLink also offers a comprehensive software SDK plus a hardware design combination, aimed at becoming the infrastructure for more DePIN projects.