Cisco Systems UBR10012 High Availability Features

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Cisco uBR10012 Universal Broadband Router Software Configuration Guide

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Chapter1 Overview of CiscouBR10012 Universal Broadband Router Software Supported Software Features for the CiscouBR10012 Router

With this feature, the user is able to select either Unsolicited Grant Services (UGS) or Real Time Polling

Service (rtPS) scheduling types, as well as packet-based or TDM-based scheduling. Low latency

queueing (LLQ) emulates a packet-mode-like operation over the Time Division Multiplex (TDM)

infrastructure of DOCSIS. As such, the feature provides the typical tradeoff between packets and TDM:

with LLQ, the user has more flexibility in defining service parameters for UGS or rtPS, but with no

guarantee (other than statistical distribution) regarding parameters such as delay and jitter.

Restrictions

•To ensure proper operation, Call Admission Control (CAC) must be enabled. When the Low

Latency Queueing (LLQ) option is enabled, it is possible for the upstream path to be filled with so

many calls that it becomes unusable, making voice quality unacceptable. CAC must be used to limit

the number of calls to ensure acceptable voice quality, as well as to ensure traffic other than voice

traffic.

•Even if CAC is not enabled, the default (DOCSIS) scheduling mode blocks traffic after a certain

number of calls.

•Unsolicited Grant Services with Activity Detection (UGS-AD) and Non Real Time Polling Service

(nrtPS) are not supported.

cable upstream n scheduling type

Use this new command to turn the various scheduling modes on or off, where n specifies the upstream

port.

Router(config-if)# [no] cable upstream n scheduling type [ugs | rtps] mode [llq | docsis]

For additional information about scheduler enhancements on the Cisco CMTS, refer to the following:

•Cisco CMTS Feature Guide — Configuring Upstream Scheduler Modes on the Cisco CMTS

http://www.cisco.com/en/US/products/hw/cable/ps2217/products_feature_guide_book09186a0080

19b6bd.html

•DOCSIS 1.1 for the Cisco CMTS

http://www.cisco.com/en/US/products/hw/cable/ps2217/products_feature_guide_chapter09186a00

8019b57f.html

High Availability Features

Several powerful High Availability features are supported on the Cisco uBR10012 router:

•Automatic Revert Feature for HCCP N+1 Redundancy Switchover Events

•Backup Path Testing for the Cisco RF Switch

•DSX Messages and Synchronized PHS Information

•Factory-Configured HCCP N+1 Redundancy

•Globally Configured HCCP 4+1 and 7+1 Redundancy on the Cisco uBR10012 Router

•HCCP N+1 Redundancy Supporting DOCSIS 1.1 for the Cisco CMTS

•HCCP Timing and Error Enhancements in HCCP Redundancy Show Commands