Motorola BSR 2000, Configuration And Management Manual

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BSR 2000 Configuration and Management Guide Release 1.0
6-20 MGBI 526360-001-00 Rev. B
In addition to the QPSK and 16 QAM modulations available in DOCSIS 1.0 and
1.1, DOCSIS 2.0 adds: 8QAM, 32Qam and 64QAM.
■
Additional Forward Error Correction (FEC) (16 correctable bytes per codeword)
■
Additional burst protection through byte interleaving
■
Additional multipath protection (24 tap equalizer)
Logical Channels
For DOCSIS 1.0 and 1.1, a single channel was associated with each single physical
port on a BSR 2000. DOCSIS 2.0 introduces the ability to have
logical
upstream
channels on each single physical port. Logical channels allow accommodation of
DOCSIS 1.0 and 1.1 (legacy) cable modems in a DOCSIS 2.0 environment.
Channel Types
DOCSIS 2.0 allows operators to assign a
channel type
to each logical channel
associated with a physical port. A channel type allows (or restricts) the kind of cable
modem (DOCSIS 2.0, 1.1, or 1.0 compliant) that can operate over the logical channel
to which the channel type is assigned. Available channel types are listed in
Table 6-1 :
Table 6-1 Channel Types Supported by DOCSIS 2.0
Channel Type DOCSIS Specification Type Comment
TDMA (Time Division Multiple
Access) Type 1 DOCSIS 1.0 and 1.1 only channel
type
MTDMA (Mixed TDMA and
A-TDMA) Type 2 DOCSIS 2.0, DOCSIS 1.1 and 1.0
channel type
A-TDMA (Advanced TDMA) Type 3A DOCSIS 2.0 only channel type
S-CDMA (Synchronous Code
Division Multiple Access) Type 3S DOCSIS 2.0 only channel type