The International Telecommunications Union Telecommunications Standardization Sector (ITU-T) has approved the various versions of DOCSIS as international standards. DOCSIS 1.0 was ratified as ITU-T Recommendation J.112 Annex B (1998), but it was superseded by DOCSIS 1.1 which was ratified as ITU-T Recommendation J.112 Annex B (2001). Subsequently, DOCSIS 2.0 was ratified as ITU-T Recommendation J.122. Most recently, DOCSIS 3.0 was ratified as ITU-T Recommendation J.222 (J.222.1J.222.2J.222.3).
Note: While ITU-T Recommendation J.112 Annex B corresponds to DOCSIS/EuroDOCSIS 1.1, Annex A describes an earlier European cable modem system (“DVB EuroModem”) based on ATM transmission standards. Annex C describes a variant of DOCSIS 1.1 that is designed to operate in Japanese cable systems. The ITU-T Recommendation J.122 main body corresponds to DOCSIS 2.0, J.122 Annex F corresponds to EuroDOCSIS 2.0, and J.122 Annex J describes the Japanese variant of DOCSIS 2.0 (analogous to Annex C of J.112).
The main differences account for differing TV channel bandwidths; European cable channels conform to PAL TV standards and are 8 MHz wide, whereas in North-America cable channels conform to NTSC standards which specify 6 MHz. The wider bandwidth in EuroDOCSIS architectures permits more bandwidth to be allocated to the downstream data path toward the user. EuroDOCSIS certification testing is executed by Excentis formerly known as tComLabs, while DOCSIS certification testing is executed by CableLabs.
The International Telecommunications Union Telecommunications Standardization Sector (ITU-T) has approved the various versions of DOCSIS as international standards. DOCSIS 1.0 was ratified as ITU-T Recommendation J.112 Annex B (1998), but it was superseded by DOCSIS 1.1 which was ratified as ITU-T Recommendation J.112 Annex B. Most recently, DOCSIS 3.0 was ratified as ITU-T Recommendation J.222 (J.222.1J.222.2J.222.3).
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