Socialization and Implementation of the North Sumatra Coffee Traceability System based on GPS and Blockchain in Simalungun Regency The Medan State Polytechnic Research Team conducted a Socialization and Implementation of the North Sumatra Coffee Traceability System based on GPS and Blockchain, the socialization was attended by the Simalungun Agriculture Service, PPL (Field Agricultural Extension Workers) and coffee farmers in Simalungun Regency, this activity was held on Thursday, August 7, 2025 at Antara Cafe