Troubleshooting guide

CHAPTER
7-1
Cisco Broadband Local Integrated Services Solution Troubleshooting Guide
OL-5169-01
7
Troubleshooting the CMTS
The Cisco Universal Broadband Router (uBR7246VXR, Figure 7-1) is a modular, standards-based Cable
Modem Termination System (CMTS), as defined in the DOCSIS 1.1 specification, with an integrated
router that offers carrier-class availability and advanced IP routing capabilities for mid to large cable
headends or distribution hubs.
Connectivity to the service provider (SP) for PSTN access is through a CMTS. In the BLISS for Cable
solution the Cisco uBR7246VXR is a CMTS with features that enable it to connect cable modems on the
Hybrid Fiber Coaxial (HFC) Cable network via a Cisco MCxx cable modem card. The cable modem card
provides the interface between the Cisco uBR protocol control information (PCI) bus and the radio
frequency (RF) signal on the DOCSIS HFC network, terminating IP packets on its network interface. It
is used for aggregating traffic in the cable access portion of the network.
The Cisco uBR7246VXR integrates a CMTS system with a 7200 series router. The 7200 router portion
of the unit is based on the NPE-300 Network Processing Engine. The Cisco uBR7246VXR supports
multiprotocol, multimedia routing and bridging with a wide variety of protocols and port adapter
combinations available. The Cisco uBR7246VXR has up to six slots for port adapters, one slot for an
input/output (I/O) controller, and one slot for a network processing engine. You can place the port
adapters in any of the available slots. The chassis is fully radio frequency (RF) hardened to ensure
noise-free transmission, and all major components are hot swappable to guarantee maximum reliability.
The Cisco uBR7246VXR supports the complete Cisco line of DOCSIS 1.0-qualified and DOCSIS 1.1
based modem cards, including cable and wireless cards that are available now. The Cisco uBR7246VXR
supports 1+1 and N+1 redundancy of the cable modem cards. A range of network interfaces is also
available, including the newest line of Cisco Dynamic Packet Transport (DPT) port adapters, which
provide direct, high-speed optical connectivity combined with add-drop multiplexer capability.
Designed for large cable deployments with tens of thousands of subscriber modems, telephones, and
other IP-enabled devices, the Cisco uBR7246VXR offers flexible expansion of DOCSIS infrastructures.
The Cisco uBR7246VXR supports a broad set of residential and commercial service offerings, including
IP telephony, multicast, streaming media, and Virtual Private Network (VPN) applications. Although the
Cisco uBR7246VXR can filter on higher-layer TCP or UDP protocols, these protocols are typically
passed transparently.
For complete technical documentation on the Cisco uBR7246VXR Universal Broadband Router see
http://www.cisco.com/en/US/products/hw/cable/ps2217/prod_technical_documentation.html.