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Working with operators and vendors, CableLabs was able to achieve a harmony agreement between General Instrument and Scientific-Atlanta covering cross licensing of various proprietary technologies including modulation, encryption and forward error correction. This was a pivotal step toward achieving open, standards-based approach to digital signal delivery. Five vendor authors were enlisted to help create specifications and in March 1997, the group issued what was called the Data over Cable Service Interface Specification (DOCSIS®).

In the summer of 1997 CableLabs staff began testing first generation modems in an incubator laboratory, which is the predecessor of today's interoperability and certification laboratories at CableLabs. The DOCSIS process was characterized by a degree of operator-vendor cooperation with CableLabs in the middle of the effort.

During a series of interoperability testing sessions in a pre-competitive laboratory setting, vendors actively lent assistance to one another.

• CableLabs created its own cable modem traffic tester software to manage the simultaneous testing of up to 80 cable modems on a functioning network. In addition to being used at CableLabs, the "system test suite" of testing procedures developed by the DOCSIS project was also made available to vendors, several of whom set up their own labs, individually or in groups, to perform DOCSIS compliance tests.
• Meanwhile, seven "working groups" collaborated via Internet e-mail "reflectors" on a "change control process" that provided a structure for discussing and making minor refinements to the DOCSIS specs.
• Beginning in July 1997, successive rounds of testing focused in physical-layer (PHY) interoperability (dubbed the Z0 phase), then testing of prototype end-to-end systems (the Z1 phase), and finally, by mid-1998, of "productized" (production model) end-to-end system (the Z2 phase of the testing).
• In early 1998, within two years of the start of the DOCSIS process, a major portion of the DOCSIS specification set was adopted by the International Telecommunications Union as an official international standard (J112-B).

In March 1999, CableLabs testing resulted in the certification of modems from Thomson and Toshiba and the qualification of a cable modem termination system from Cisco. Today, hundreds of companies have produced successfully pass testing and become available for deployment in the cable industry, resulting in more choice in manufacturers and dramatically lower price points for purchase of modems. By one example, modem prices fell from $3,000 to $50 in a few years.

Today, DOCSIS has gone through versions 1.0, 1.1, 2.0 and now 3.0, in each case adding new technology and capabilities all of which are backward compatible. We now are near a point when operators will deliver hundred plus megabit per second service—in both directions—to consumers. The industry has benefited with a $15 billion per year revenue stream that comes directly from its high speed data customers, mostly residential but increasingly from business customers as well.

CableLabs continues to use the successful template of teaming MSOs, vendors and CableLabs staff in spec writing and creation. It has refined its testing process to the point that a number of test waves are ongoing simultaneously to ensure products can get into the marketplace as rapidly as possible. As one more example, the PacketCable project has followed a similar path and now serves as the common platform for a digital voice business that generates $5 billion annually for cable operators.