Recognizing the importance of standards and compatibility in helping to market new services and because of the slow progress on IEEE 802.14, North American cable system operators have settled firmly on the DOCSIS/multimedia cable network system partners (MCNS) cable modem specification developed by CableLabs, their own research and development group. The International Telecommunication Union (ITU) has also accepted DOCSIS, calling it ITU J.112. Even an accepted standard continues to evolve. In April 1999, CableLabs issued DOCSIS 1.1, adding support for IP telephony and other constant-bit-rate services. Since the newer standard is backward compatible, DOCSIS 1.0 and 1.1 cable modems can operate in the same spectrum on the same network. CableLabs is already at work on the DOCSIS 1.2 specification, which includes next-generation physical layer technology intended to enable higher-speed two-way services and allow cable companies to increase their networks' data capacity.

The situation is quite different in Europe, where two large consortia are vying to win acceptance of their competing standards.

One group, the European Cable Modem Consortium, composed of manufacturers seeking to leverage their North American MCNS/DOCSIS experience and investment, came together in October 1998 to develop and promote an ITU–compliant standard for cable modems, set-top boxes and head-end equipment. Members include Broadcom, Cisco, Dassault–AT, Deltakabel, Elsa, FUBA/General Instrument, Motorola, Pace, Samsung, Teldat, Tonna, and 3COM. "EuroDOCSIS," as their standard is known, is DOCSIS with the addition of an 8 MHz bandwidth downstream channel (within a 100 to 860 MHz spectrum), ITU–T J.83 A forward-error correction and upstream bandwidth of 5 to 65 MHz. These adaptations are all accomplished in the physical layer, leaving the media access control layer unchanged.

These modifications make EuroDOCSIS compatible with its major European competitor—digital video broadcasting (DVB), developed by the DVB/Digital Audio Video Council (DAVIC) Interoperability Consortium. Coincidentally or not, this consortium was also founded in October 1998 by Alcatel, Cocom, DiviCom, Hughes Network Systems, Nokia, Sagem, Simac, Thomson Broadcast Systems, and Thomson Multimedia.

Though the European standards battle is not necessarily over, DVB appears to be winning. In April 2000, the European Telecommunications Standards Institute (ETSI) officially accepted DVB for the interaction channel for cable systems. The DVB/DAVIC Interoperability Consortium claims this makes DVB the only accepted standard in Europe for data communication over HFC networks. ETSI ES 200 800, as the standard is known, covers both cable modems and set-top boxes and meets the requirements established by the European Cable Communications Association (ECCA) specifications for the "EuroModem" and "EuroBox." Cable operators belonging to the EuroModem Consortium, with more than 25 million subscribers among them, have estimated an immediate need for up to 500,000 EuroModem cable modems as soon they become available. The first mass rollout was announced in August 2000, when BV of the Netherlands signed an agreement to supply a minimum of 20,000 units in 12 months to Essent Kabelcom, one of the Netherlands' largest cable operators.