996, cable operators Comcast, Cox, TCI, and Time Warner, operating under a limited partnership dubbed Multimedia Cable Network System Partners Ltd. (MCNS), issued a request for proposals (RFP) to retain a project management company to research and publish a set of interface specifications for high-speed cable data services by the end of the 1996 (Van Matre, 1999). MCNS released its Data Over Cable System Interface Specification (DOCSIS) for cable modem products to vendors in March 1997. Afterwards, IEEE released its standard, but by that time, the cable operators had already wed themselves to the MCNS DOCSIS standard. To date, more than 20 vendors have announced plans to build products based on the MCNS DOCSIS standard. The cable companies MediaOne (formerly Continental Cablevision), Rogers Cablesystems, and CableLabs, also signed on to the DOCSIS RFP. Together, this coalition represents the majority of the North American cable industry, serving 85% of U.S. cable subscribers and 70% of Canadian subscribers. Even though DOCSIS is the dominant US cable data network standard, it has yet to be formally certified by any independent standards body. The DOCSIS requirements are now managed by CableLabs. A CableLabs certification program administers vendor equipment compliance to the DOCSIS requirements and interoperability tests. Standardized DOCSIS cable modems started shipping in limited quantities in the third and fourth quarters of 1998 with wider availability expected in the first quarter of 1999. No major vendors are currently building modems based on the initial IEEE standard (Van Matre, 1999). The differing cable modem specifications advocated by IEEE 802.14 and MCNS reflect the priorities of each organization. IEEE 802.14 is a vendor-driven group, and has focused on a creating a future-proof standard based on industrial-strength technology. The MSO members of MCNS, on the other hand, are far more concerned with minimizin...
