DOCSIS
DOCSIS was originally developed by CableLabs and contributing companies, including Arris, BigBand Networks, Broadcom, Cisco, Comcast, Conexant, Correlant, Cox, General Instrument, Harmonic, Intel, Motorola, Netgear, Terayon, Time Warner Cable, and Texas Instruments.
[14] As frequency allocation bandwidth plans differ between United States and European CATV systems, DOCSIS standards earlier than 3.1 have been modified for use in Europe.
The differences between the bandwidths exist because European cable TV conforms to PAL/DVB-C standards of 8 MHz RF channel bandwidth and North American cable TV conforms to NTSC/ATSC standards which specify 6 MHz per channel.
DOCSIS 3.1 supports a downstream throughput with 4096-QAM and 25 kHz subcarrier spacing of up to 1.89 Gbit/s per 192 MHz OFDM channel.
[citation needed] Traditional DOCSIS upstream in North America uses the 5–42 MHz frequency range.
[28] DOCSIS 2.0 was also used over microwave frequencies (10 GHz) in Ireland by Digiweb, using dedicated wireless links rather than HFC network.
At each subscriber premises the ordinary CM is connected to an antenna box which converts to/from microwave frequencies and transmits/receives on 10 GHz.
[29] DOCSIS includes media access control (MAC) layer security services in its Baseline Privacy Interface specifications.
Most recently, a number of enhancements to the Baseline Privacy Interface were added as part of DOCSIS 3.0, and the specification was renamed "Security" (SEC).
The intent of the BPI/SEC specifications is to describe MAC layer security services for DOCSIS CMTS to cable modem communications.
The earlier BPI specification (ANSI/SCTE 22-2) had limited service protection because the underlying key management protocol did not authenticate the user's cable modem.
Successful attacks often occur when the CMTS is configured for backward compatibility with early pre-standard DOCSIS 1.1 modems.
These modems were "software upgradeable in the field", but did not include valid DOCSIS or EuroDOCSIS root certificates.
