Up until 2006, he was the manager of Computing Facilities at the Department of Computer Science at the University of British Columbia where he administered the .ca registry on a volunteer basis from 1987 to December 2000. John has served on the Board of BCNET and is a founding member of the Canadian Internet Registration Authority (CIRA) Board of Directors.
In September, 2008, the University of British Columbia named a student learning center after him.
Some of his accomplishments include: managing the Canadian academic and research network CDNnet (1985-1990); helping to establish a connection to the U.S. NSFnet (1988); hosting the first Internet Engineering Task Force (IETF) meeting held outside of the U.S. (1990); sitting on the board of the BCNET Networking Society (1996-2001); and participating in CA*net, the Coordinating Committee on Intercontinental Research Networking, CANARIE, and the Internet Society (ISOC). John helped to create the .ca domain in 1987 and was its initial registrar, serving in that capacity and chairing the .ca Domain Committee until 2000.
Mr. Demco was honoured with the 2006 Canadian New Media Lifetime Achievement award and along with Cybele Negris, Matthew Lane and Stephen Smith, a finalist for Ernst & Young's 2005 Entrepreneur of the Year Awards for Information Technology in the Pacific Region.
In 2013, he was given the Queen Elizabeth II Diamond Jubilee Medal by Mayor of Surrey in recognition for his contributions to the Canadian Internet.
He participated in the Canadian Domain Name Consultative Committee which made recommendations concerning the structure and organization of the .CA domain. He helped to establish CIRA, and is a founding member of its Board of Directors.