Docsis 1.1 Feature Support - Cisco 7246VXR - uBR Router Software Configuration Manual

Chapter 1 Overview of Cisco uBR7200 Series Software
Concatenation for DOCSIS 1.0+
Concatenation allows a cable modem to send several packets in one large burst, instead of having to
make a separate grant request for each.
All DOCSIS 1.0 extensions are available only when using a cable modem (such as the Cisco uBR924
Caution
cable access router) and CMTS (such as the Cisco uBR7200 series router) that support these extensions.
The cable modem activates the use of the extensions by sending a dynamic MAC message. DOCSIS 1.0
CMs continue to receive DOCSIS 1.0 treatment from the CMTS.
Dynamic MAC messages
The Dynamic Service Addition (DSA) and Dynamic Service Deletion (DSD) messages allow dynamic
SIDs to be created and deleted on demand so that the bandwidth required for a voice call can be allocated
at the time a call is placed and then freed up for other uses when the call is over.
Multiple SIDs per Cable Modem
This feature creates separate service flows for voice and data traffic. This allows the CMTS and cable
modem to give higher priority for voice traffic, preventing the data traffic from affecting the quality of
the voice calls.
Separate Downstream Rates
This feature provides an ability to provide separate downstream rates for any given cable modem, based
on the IP-precedence value in the packet—This helps separate voice signaling and data traffic that goes
to the same ITCM to address rate shaping purposes.
Unsolicited Grant Service (CBR-scheduling) on the Upstream
This feature helps provide a higher-quality channel for upstream VoIP packets from an Integrated
Telephony Cable Modem (ITCM) such as the Cisco uBR924 cable access router.

DOCSIS 1.1 Feature Support

DOCSIS 1.1 is the first major revision of the initial DOCSIS 1.0 standard for cable networks. Although
the initial standard provided quality data traffic over the coaxial cable network, the demands of real-time
traffic such as voice and video required many changes to the DOCSIS specification.
This section describes the major enhancements supported on the Cisco uBR7200 series:
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OL-2239-05
http://www.cisco.com/en/US/tech/tk86/tk168/technologies_q_and_a_item09186a0080094eb2.sht
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Baseline Privacy Interface Plus (BPI+), page 1-58
Burst Profile Configuration, page 1-58
Cable Modulation Profile Default Templates, page 1-58
DHCP Cable Modem Host ID, page 1-59
DHCP Client ID/Remote ID Options, page 1-59
DHCP, Time of Day (ToD) and TFTP Servers, page 1-60
DOCSIS 1.1 Quality of Service Features, page 1-60
Cisco uBR7200 Series Universal Broadband Router Software Configuration Guide
Supported Software Features for the Cisco uBR7200 Series
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