By Gordon L. Bechtel, Jeffrey A. Masucci and L. Kathy Bechtel, Stout Technologies, Inc. and Pamela Anderson, CableLabs
A new, open specification for Hybrid Fiber/Coax (HFC) based outside plant (OSP) status monitoring equipment is becoming available. It details the physical and data link layer protocols, the core message set and the transponder electromechanical interface to be used by HFC status monitoring equipment. It has been developed by CableLabs and its member companies through a cooperative process with the vendor community. The status monitoring specification provides the structure necessary for vendor interoperability, while allowing vendors 'room' for innovation and product differentiation. Communication is based on twoway burst packet FSK (Frequency Shift Keying) transmission and employs a combination of poll-response and contention based multiple access schemes. The message set provides the means and the structure for communicating information to and from outside plant status monitoring equipment. It is simple, optimized for speed, and extensible. The electromechanical specification provides versatile interconnection between the transponder and the monitored equipment.