Data Over Cable Service Interface Specification definition communications, networking
-approved interface requirements for cable modems involved in high-speed data distribution over a cable television
network. DOCSIS compatible equipment uses a 6 MHz carrier
band for downstream
, using 64 and 256 QAM
(ITU Annex B), and QPSK and 16 QAM for upstream
, allowing up to 36 and 10 Mb/s, respectively for downstream and upstream channels.
CableLabs FAQ (http://cablemodem.com/FAQs.html).