The real-time rings are self-configurable and run without the complex configuration steps required by other alternatives. They provide a recovery time of less than 5mS per hop and allow more than 50 switches to be connected in a ring. These features are well-suited for real-time, deterministic control and distributed systems. Several models of the Real-time Ring Switch offer different combinations of copper and fiber ports for connections up to 40km or more. Reliability and support features include more than 1 million hours MTBF, a 20-year support and service policy, and free field-installable upgrades.