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Universal Edge Quadrature Amplitude Modulation
The Universal EQAM platform integrates the capabilities of an M-CMTS EQAM platform and the
capabilities of a video EQAM, thereby supporting both DOCSIS and digital video services in a single
UEQAM platform. The granularity of the DOCSIS and video traffic mix is per 4-channel group, that is,
per RF port.
The Universal EQAM can be configured with 64 QAM or 256 QAM Downstream Modulation with 1:4
Frequency Stacking under Annex B, Annex A, or Annex C.
M-CMTS DOCSIS MPEG Transport Manual Mode
The interface between the M-CMTS core and the EQAM is defined by Downstream External PHY
Interfaces (DEPI), which is an L2TP-based IP tunnel containing both a data path for DOCSIS frames
and a control path for session setup, maintenance, and tear-down. This feature supports the DEPI data
path with the DOCSIS MPEG Transport (D-MPT) mode with manual configuration for session setup.
D-MPT places integer number of MPEG transport packets into the L2TP payload. Only one D-MPT flow
can be present in a QAM channel. The EQAM extracts the D-MPT packets within the DEPI payload and
forwards them to the output QAM.
The D-MPT feature supports bonded DOCSIS through downstream channel bonding. Channel bonding
is a technique of grouping multiple QAM channels into a bonding group to provide a logical downstream
channel with larger aggregated bandwidth. Bonded traffic can be encapsulated in D-MPT.
D-MPT traffic from the M-CMTS core contains SYNC messages (DOCSIS time stamps). The EQAM
finds all the SYNC messages in the D-MPT payload and performs the SYNC correction.
DTI Offset
The DOCSIS Timing Interface (DTI) Offset feature enables DOCSIS timing offset adjustment per
channel in the RFGW-10 DS-48 line card. The operator must measure the actual timing offset adjustment
required on each QAM channel first and then use the DTI Offset CLI to make the adjustment. To
configure all the QAM ports to the same timing offset, use the cable depi offset command specifying
the port range of the QAM interfaces. With this command, users can configure an entire chassis with the
same timing offset.
1:1 and 1:N DS-48 Line Card Redundancy
The RFGW-10 supports both 1:1 and 1:N line card redundancy schemes. 1:1 redundancy refers to a
configuration where a line card has a dedicated backup card. 1:N redundancy means one line card
protecting N line cards. Therefore, a single DS-48 line card can protect as many as nine other line cards.
There can be up to two line card redundancy groups in an RFGW-10 chassis with each group being 1:1
or 1:N redundancy.
The RFGW-10 performs line card switchover on such events as a user-initiated switchover command,
line card insertion and removal (OIR), as well as hardware and software faults, RF upconverter failure,
and DTI failure on the line card. At line card switchover, the standby line card becomes active, resuming
the functions of the line card it is switched from. With the internal RF Switch card, line card switchover
is transparent to the RF connections to the plant.
The line card redundancy supports M-CMTS D-MPT traffic. The line card switchover has little impact
on the DOCSIS applications. This release does not provide line card redundancy support for video
applications.
OL-18677-10
Release Notes for Cisco RF Gateway 10 in Cisco IOS Release 12.2SQ
New and Changed Information
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