Cable Downstream Annex - Cisco SR2016T-NA Reference Manual

cable downstream annex

cable downstream annex
To set the Motion Picture Experts Group (MPEG) framing format for a downstream port on a cable
interface line card to either Annex A (Europe) or Annex B (North America), use the cable downstream
annex command in cable interface configuration mode.
Syntax Description
A
B
Defaults Annex B for all Cisco cable interface cards other than the Cisco uBR-MC16E. Annex A, if using the
Cisco uBR-MC16E cable interface line card and the Cisco uBR7111E and Cisco uBR7114E universal
broadband routers.
Command Modes Interface configuration (cable interface only)
Command History Release
12.1(1a)T1
12.0(7)T, 12.1(1a)T1,
12.1 mainline,
12.0(8)SC, 12.1(2)EC1
12.1(7)EC
12.2(15)CX
12.2(15)BC2
Usage Guidelines
The MPEG framing format must be compatible with the downstream symbol rate you set. Annex B is
the North America (DOCSIS) standard and Annex A is the European (EuroDOCSIS) standard. You
should review your local standards and specifications for downstream MPEG framing to determine
which format you should use.
The Cisco uBR-MC16U/X, Cisco uBR-MC28U/X, and Cisco uBR-MC5X20U cable interface line cards
support both Annex A and Annex B operation. However, on the Cisco uBR-MC28U/X, both
downstreams must be configured for the same mode (either both Annex A or both Annex B).
On the Cisco uBR-MC16U and Cisco uBR-MC28U (with integrated upconverter), the IF frequency is
fixed at 44 MHz for both Annex A and Annex B modes of operation. On the Cisco uBR-MC16X and
Cisco uBR-MC28X (without integrated upconverter), the IF frequency is set to 36.125 MHz in Annex A
mode and 44 MHz in Annex B mode.
Cisco Broadband Cable Command Reference Guide
2-46
cable downstream annex {A | B}
Annex A. The downstream uses the EuroDOCSIS J.112 standard.
Annex B. The DOCSIS-compliant cable plants that support North American channel plans
use ITU J.83 Annex B downstream radio frequency.
Modification
This command was introduced.
Support for Annex A was introduced for the Cisco uBR-MC16E cable
interface line card.
Support for Annex A was added for the Cisco uBR7111E and
Cisco uBR7114E universal broadband routers.
Support was added for both Annex A and Annex B on the
Cisco uBR-MC16U/X and Cisco uBR-MC28U/X cable interface line cards.
Support was added for both Annex A and Annex B on the
Cisco uBR-MC5X20U/S cable interface line cards.
Chapter 2 Cisco CMTS Configuration Commands
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