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Cisco uBR7100 Series Software Configuration Guide
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Preface
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Chapter 1: Overview of Cisco uBR7100 Series Software
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Chapter 2: Configuring the CMTS for the First Time
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Chapter 3: Configuring the Cisco Cable Modem Card
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Chapter 4: Configuring Basic Broadband Internet Access
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Chapter 5: Troubleshooting the System
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Appendix A: Configuration Register Information for the Cisco uBR7100 Series Universal Broadband Router
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Table Of Contents
Overview of Cisco uBR7100 Series Software
Cisco IOS Releases and Images for the Cisco uBR7100 Series
Determining Your Cisco IOS Software Release
Upgrading to a New Software Release
12.2 BC Release Train and Images
Cisco IOS 12.2(15)BC2b Images and Requirements
12.1 EC Release Train and Images
Cisco IOS 12.1 EC Images and Requirements
Cisco uBR7100 Series Router Configuration Tools
Cable Modem Configuration File Editor
Supported Software Features for the Cisco uBR7100 Series
Cisco uBR7100 Series Features and Cisco IOS Releases
DOCSIS and CMTS Interoperability
Automatic Provisioning of Cable Modems
Overview of Cisco uBR7100 Series Software
The Cisco uBR7100 series uses Cisco IOS® software to offer enhanced stability, features, performance and investment protection. This chapter summarizes system and software features of the Cisco uBR7200 series Cable Modem Termination System (CMTS). This chapter contains the following sections:
Describes the supported Cisco IOS release trains, associated features, and latest Cisco IOS images for each recently supported train.
One early step in CMTS feature configuration is to verify your Cisco IOS release train, the associated image and feature set. This section guides you in determining such information.
Provides an overview of the configuration tools available when choosing your configuration method.
"Supported Software Features for the Cisco uBR7100 Series," page 6
Describes the features and configuration utilities that are available on the Cisco uBR7100 series.
Provides an overview of DOCSIS NTSC and EuroDOCSIS cable plants, DOCSIS-compliant signals, and traffic engineering.
Cisco IOS Releases and Images for the Cisco uBR7100 Series
The Cisco uBR7100 series router runs the IOS image that is located on the Type II Personal Computer Memory Card International Association (PCMCIA) Flash memory disks. These disks are located in the two PCMCIA slots in the primary Performance Routing Engine 1 (PRE1). A PCMCIA disk in either slot can store a Cisco IOS image or configuration file.
In addition to the Flash memory disks, each PRE1 module contains onboard Flash memory that is used to store a boot loader. The loader executes following a system reset to reload and execute the Cisco IOS software on the Flash memory disks.
The PRE1 module also stores the system configuration in the onboard Flash memory. The configuration information read from the Flash memory is buffered in operational memory following initialization, and is written to the Flash memory device when you save the configuration.
Each line card also contains onboard Flash memory that is used to store a boot loader, similar in function to that used on the PRE1 module. However, the line card loader executes following a system reset, line card reset, or line card insertion to reload and execute any code that must run on the line card for it to operate properly. Software images may also be stored on an external TFTP server. If the Cisco uBR7100 series router is so configured, it then downloads the proper image from the TFTP server and executes it.
This section describes the supported releases, latest images, memory requirements, and major software features for the following Cisco IOS software:
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Determining Your Cisco IOS Software Release
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Cisco IOS Software Location
Cisco IOS software is stored on the PRE1 module, which includes two PCMCIA slots that are accessible from the front panel. Either slot can store an IOS image or configuration file.
The Flash memory on the PRE1 module is used to store a simple ROM monitor or boot loader. The loader executes following a system reset, line card reset, or line card insertion.
Line card images may also be stored in PRE1 module Flash memory or on an external TFTP server.
The PRE1 module stores the system configuration in a 512 KB NVRAM device. Configuration information read from NVRAM is buffered in RAM following initialization and is written to the device when you save the configuration.
Determining Your Cisco IOS Software Release
To determine the version of Cisco IOS software running on the Cisco uBR7100 series router, log in to the router and enter the show version command in privileged EXEC mode. For example:
Router> show versionCisco Internetwork Operating System SoftwareIOS (tm) 12.2 XF Software (ubr10k-k8p6-mz), Version 12.2 XF, RELEASE SOFTWAREUpgrading to a New Software Release
An upgrade is an order placed for a Cisco IOS® feature set that contains more functionality than the one that you are replacing. And upgrade is not an update. An update consists of installing a more recent version of the SAME feature set. Exception— If a feature set has been made obsolete, the next, closest feature set, on a more recent release, will be considered an update.
For general information about upgrading to a new software release, refer to the Cisco IOS Upgrade Ordering Instructions on Cisco.com.
12.2 BC Release Train and Images
The 12.2 BC train is an interim release train that provides DOCSIS 1.1 two-way support, along with support for selected new features.
Cisco IOS Release 12.2(4)BC1b, provides a migration path from the earlier 12.2 XF releases. Cisco IOS Release 12.2(4)BC1b supports the Cisco uBR7100 universal broadband router, which provides a high-capacity, high-throughput cable modem termination system (CMTS), optimized for aggregating traffic at the edge of the cable network. Designed for cable operators and service providers, the platform connects residential subscribers via cable modems, digital set-top boxes, or IP telephony cable modems for high-speed data, broadband entertainment, and IP telephony solutions.
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Cisco IOS 12.2(15)BC2b Images and Requirements
Table 1-1 displays the memory recommendations of the Cisco IOS feature sets for the Cisco uBR7100 universal broadband router for Cisco IOS Release 12.2(4)BC1b. Cisco uBR7100 universal broadband routers are available with a 48-MB or 120-MB Type II PCMCIA Flash memory card.
The image subset legend for Table 5 is as follows:
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http://www.cisco.com/univercd/cc/td/doc/product/cable/ubr7100/ub7100rn/index.htm
12.1 EC Release Train and Images
Release 12.1 EC is an early deployment (ED) release based on Release 12.1 E, which serves as the train's starting point. Release 12.1 E, in turn, is based on Release 12.1 Mainline. Early deployment releases contain fixes to software caveats as well as support for new Cisco hardware and software features. Feature support is cumulative from release to release, unless otherwise noted.
Cisco IOS 12.1 EC Images and Requirements
Table 1-2 displays the memory recommendations of the Cisco IOS feature sets for the Cisco uBR7100 universal broadband router for Cisco IOS Release 12.2(11)CY. Cisco uBR7100 universal broadband routers are available with a 48-MB or 120-MB Type II PCMCIA Flash memory card.
Table 1-2 displays the memory recommendations of the Cisco IOS feature sets for the Cisco uBR7100 series universal broadband routers for Cisco IOS Release 12.1(20)EC2. Cisco uBR7100 series universal broadband routers are available with a 16-MB or 20-MB Type II PCMCIA Flash memory card.
The image subset legend for Table 3 is as follows:
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http://www.cisco.com/univercd/cc/td/doc/product/cable/ubr7100/ub7100rn/index.htm
Cisco uBR7100 Series Router Configuration Tools
Cisco Network Registrar (CNR)
Cisco provides the Cisco Network Registrar (CNR) with each Cisco uBR7100 series router. CNR dramatically improves the reliability of naming and addressing services for enterprise and service provider networks. CNR provides scalable DNS and DHCP services and forms the basis of a DOCSIS cable modem provisioning system.
CNR is a configuration tool that automates dynamic IP address allocation to cable interfaces, PCs, and other devices on the broadband network. CNR allows you to track serial numbers and MAC addresses for each cable interface on your network, and reduces customer service involvement when tracking subscriber CPE equipment.
For additional information about using CNR, refer to the latest CNR documentation at Cisco.com.
DOCSIS CPE Configurator
Cisco also offers an HTML-based DOCSIS CPE Configurator tool that can be accessed from Cisco.com. The tool is designed to collect information needed to generate a DOCSIS CM configuration file. The generated file is in binary format consistent with the DOCSIS RF Specification (SP-RFI-105-991105).
Cable Modem Configuration File Editor
The Cisco uBR7100 series routers support the cable config-file command, which provide for the online creation of DOCSIS configuration files, which can then be stored on the router's Flash memory or copied to a TFTP server. The CLI commands to create these configuration files can be part of the Cisco IOS configuration file that the router loads on power-up so that they are immediately available to cable modems on the network.
Supported Software Features for the Cisco uBR7100 Series
This section summarizes Cisco uBR7100 series router software features for all supported Cisco IOS Release trains, and directs you to additional configuration information for each feature.
Cisco uBR7100 Series Features and Cisco IOS Releases
Table 1-3 summarizes the software-related features and related Cisco IOS releases that support the Cisco uBR7100 series router. Cisco IOS features indicate the first release in which the feature was introduced. Unless otherwise noted, feature support continues in later releases of the same or related Cisco IOS release train.
Features are organized in the following categories:
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Table 1-3 Cisco uBR7100 Series Feature List with First Supporting Release Train
Cisco Command-Line Enhancements
Configurable registration timeout
12.1 EC
Changes the CM registration value (the T9 timer); the cable registration-timeout minutes command sets the T9 timer to the new value (from 2 to 60 minutes). The no cable registration-timeout command resets the T9 timer to its default of 3 minutes.
Statistical values added to show controller int cx/y upstream command
12.1 EC
Displays the following additional statistical counters in the output of the show controller cx/0 upstream number command:
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WCCP and WCCPv2
12.1 EC
Identifies the web caching protocols supported.
Show Controllers Cable Enhancement
12.2 BC
The Show Controllers Cables Extensions feature has been supported for Cisco IOS Release 12.2(15)BC2b.
In this feature, the mem-stats, memory, proc-cpu, and tech-support keywords execute the related command on the processor that runs on are added to obtain the relevant information from the onboard processor on Broadband Processing Engine (BPE) cable interface line cards, such as the Cisco uBR-MC16U/X, Cisco uBR-MC28U/X, and Cisco uBR-MC5X20S/U cards. This allows the user to obtain information that is specific for that particular cable interface card, as opposed to having to run these commands on the entire router.
Refer to Cisco uBR7100 Series - Cisco IOS Release 12.2 BC:
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Cisco Quality of Service Features
Cisco express forwarding (CEF)
12.1 EC
Supports Cisco's processing switching protocol to enable traffic decisions to be made quickly.
Committed access rate (CAR)
12.1 EC
Provides the means to allocate and limit bandwidth to traffic sources and destinations, and specify policies to handle traffic exceeding the bandwidth allocation. CAR policies can be utilized at the ingress or egress of the network. The feature uses token bucket filters to measure traffic load and limit sources to bandwidth allocations.
DOCSIS 1.0 QoS extensions
12.1 EC
Allows the Cisco uBR7100 series to specify priority service flows higher than those specified in DOCSIS 1.0.
Downstream rate shaping
12.1 EC
Supports buffering downstream grants to rate-exceeding cable interfaces, without incurring TCP-related timeouts and retransmits.
Downstream rate shaping with ToS
12.1 EC
Enables to be partitioned into multiple classes of service. Uses the three precedence bits in the ToS field in the IP header to specify class of service assignment for each packet.
Those packets with the IP precedence bit set in the IP packet are given higher priority. This allows the CMTS administrator to calculate the data rate for a given flow, in addition to the data rate configured on a per cable modem basis.
Multi-SID support
12.1 EC
Allows the Cisco uBR7100 series to support the definition of multiple SIDs on the upstream. This includes multiple service classes per cable interface, enabling administrators to delegate higher priority as required.
QoS profile enforcement
12.1 EC
Allows the Cisco uBR7100 series to override the provisioned service class of a cable interface at the time of registration with a CMTS-defined QoS profile.
Resource Reservation Protocol (RSVP)
12.1 EC
Works in conjunction with WFQ; helps the router establish a weight for different types of packets that affect the order in which the packets enter the output queue and are placed on the cable network for transmission; that is, higher priority packets are routed through the interface with a QoS method that allows the packets to receive priority over standard data frames. A router that supports RSVP gives priority to packets that fall into a reservation within RSVP.
TAG/NetFlow switching
12.1 EC
Provides high performance for network layer services, enabling per-flow application of network services such as security and traffic accounting. Data collected for each flow includes:
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Upstream rate (traffic) shaping
12.1 EC
Supports buffering upstream grants from rate-exceeding cable interfaces, without incurring Transmission Control Protocol (TCP)-related timeouts and retransmits.
Weighted fair drop (WFD) enhancements
12.1 EC
In addition to other traffic shaping techniques, a new configuration field associates a maximum bandwidth in kbps with a particular setting of IP type of service (ToS) bits. This can be used to ensure that certain traffic, such as data, does not exceed a preset rate limit and thereby interfere with higher priority real time traffic.
Weighted fair queuing (WFQ)
12.1 EC
Performs priority output queuing and custom queuing to grant resources to important sessions when network bandwidth is saturated; typically used for digitized higher priority real time packets to help reduce delay. WFQ provides expeditious handling for high priority traffic, requiring low delay, while fairly sharing the remaining bandwidth between lower priority traffic. WFQ divides link traffic into high and low priority flows based on metrics including IP precedence and traffic volume.
Weighted random early detection (WRED)
12.1 EC
Provides the ability to specify traffic handling policies to maximize throughput under congestion conditions. RED works in conjunction with TCP to intelligently avoid network congestion. WRED combines IP precedence and RED capabilities to provide differentiated performance characteristics for different classes of service, thus providing preferential traffic handling for higher priority traffic. Administrators can define minimum and maximum queue depth thresholds and drop probabilities for each class of service.
DHCP Servers and Feature Support
DHCP cable modem host ID
(also known as cable modem and host subnet addressing)
12.1 EC
(also known as cable modem and host subnet addressing)Allows the Cisco uBR7100 series to modify the giaddr field of DHCPDISCOVER packets, based on whether the source is a cable interface or a host. This helps automate provisioning.
Integrated DHCP server
12.1 EC
Simplifies provisioning, offering an integrated Dynamic Host Configuration Protocol server.
Source Verify Lease-Query Throttling
12.2 BC
When the cable source-verify dhcp and no cable arp commands are configured on a cable interface, problems can occur when viruses, denial of service (DoS) attacks, and theft-of-service attacks begin scanning a range of IP addresses, in an attempt to find unused addresses. When the Cisco CMTS router is verifying unknown IP addresses, this type of scanning generates a large volume of DHCP lease queries, which can result in a number of problems, such as dropped packets and high CPU utilization of both the Cisco CMTS router and DHCP server.
To prevent these problems, you can enable filtering of these requests on upstream interfaces, downstream interfaces, or both. When this feature is enabled, the Cisco CMTS allows only a certain number of DHCP LEASEQUERY requests for each service ID (SID) on an interface within the configured interval time period. If a SID generates more lease queries than the maximum, the router drops the excess number of requests until the next interval period begins.
For more information on this feature, see the document "Filtering Cable DHCP Lease Queries", at the following URL:
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Support for dynamic/mobile hosts
12.1 EC
Allows the CMTS administrator to bring up a PC behind one CM, then move it to another CM. Adds information for the hosts involved in host tables. To prevent security breaches, supports pinging the host using the old SID to verify that it has indeed been moved.
DHCP server is used to verify addresses and can be configured with the cable source-verify dhcp command; no cable arp should be configured in the CMTS to prevent it from sending ARP requests.
DOCSIS Feature Support
Concatenation support
12.1 EC
Combines multiple upstream packets into one packet to reduce packet overhead and overall latency, as well as increase transmission efficiency. Using concatenation, a CM needs to make only one bandwidth request for a concatenated packet, as opposed to making a different bandwidth request for each individual packet. This technique is particularly effective for real time traffic.
DHCP Client ID/Remote ID options
12.1 EC
Allows the Cisco uBR7100 series to report and limit the number of CPEs per cable interface through command-line interface (CLI) and Simple Network Management Protocol (SNMP).
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DOCS-IF-MIB Update
12.2(15)BC2
The DOCS-IF-MIB (released as RFC 2670) has been updated to conform to the version 5 of the DOCSIS 2.0 RF MIB Specification (draft-ietf-ipcdn-docs-rfmibv2-05.txt).
DOCSIS 1.0 Concatenation Override
12.3 BC
Cisco IOS release 12.3(13a)BC introduces support for the DOCSIS 1.0 concatenation override feature on the Cisco uBR10012 router. This feature provides the ability to disable concatenation on DOCSIS 1.0 cable modems, even in circumstances where concatenation is otherwise supported for the upstream channel.
DOCSIS 1.0 concatenation allows the cable modem to make a single-time slice request for multiple packets, and to send all packets in a single large burst on the upstream. Concatenation was introduced in the upstream receive driver in the previous Cisco IOS releases that supported DOCSIS 1.0 +. Per-SID counters were later added in Cisco IOS release 12.1(4)CX for debugging concatenation activity.
In some circumstances, overriding concatenation on DOCSIS 1.0 cable modems may be preferable, and Cisco IOS release 12.3(13a)BC supports either option.
To enable DOCSIS 1.0 concatenation override with Cisco IOS release 12.3(13a)BC and later releases, use the new docsis10 keyword with the previously supported cable upstream <n> concatenation command in privileged EXEC mode:
cable upstream <n> concatenation docsis10
Refer to Release Notes for Cisco uBR7100 Series for Cisco IOS Release 12.3 BC:
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DOCSIS 1.0 Constant Bit Rate (CBR)—DOCSIS 1.0 extension
12.1 EC
Enables better processing of higher priority traffic; new fields in the DOCSIS configuration file can be used so that when a CM requests a voice SID, the MAC scheduler on the Cisco uBR7100 series schedules fixed periodic slots on the upstream for that traffic flow. The CM does not have to contend for these slots, and because the Cisco uBR7100 series controls the timing of slots, it has precise control over potential delay and jitter.
DOCSIS 1.0 Media Access Controller (MAC) driver
12.1 EC
Supports CableLabs specifications for the MAC sublayer and associated interfaces.
DOCSIS 1.0 QoS enhancements
12.1 EC
Supports definition of service class profiles according to DOCSIS 1.0:
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DOCSIS extensions MIB
12.1 EC
Supports objects related to QoS support for scheduler of DOCSIS-compliant RF interfaces in the CMTS.
DOCSIS Set-Top Gateway (DSG) 1.0
12.2 BC
Cisco IOS Release 12.3(9a)BC introduces support for DOCSIS Set-Top Gateway (DSG) Issue 1.0 on the Cisco uBR7100 series universal broadband router. The DOCSIS Set-Top Gateway (DSG) feature allows the Cisco CMTS to provide a class of cable services known as out-of-band (OOB) messaging to set-top boxes (STBs) over existing DOCSIS networks. This allows MSOs and other service providers to combine both DOCSIS and STB operations over one, open, vendor-independent network, without any change to the existing network or cable modems.
DSG is a CableLabs® specification that allows the Cisco CMTS to provide a class of cable services known as out-of-band (OOB) messaging to set-top boxes (STBs) over existing Data-over-Cable Service Interface Specifications (DOCSIS) cable networks. DSG 1.0 allows cable Multi-System Operators (MSOs) and other service providers to combine both DOCSIS and STB operations over a single, open and vendor-independent network without requiring any changes to the existing DOCSIS network infrastructure.
At the time of this Cisco publication, the CableLabs® DOCSIS DSG specification is in the current status of "Issued" as characterized by stability, rigorous review in industry and cross-vendor interoperability.
For additional information about configuring and using DSG 1.0 on the Cisco uBR7100 Series routers, refer to the following document on Cisco.com:
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DOCSIS software infrastructure
12.1 EC
Supports CableLabs specifications for high-speed data-over-cable systems involving the following categories:
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Downstream channel ID
12.1 EC
Allows all cable interfaces on the cable network to have unique downstream channel IDs. CMs communicate their downstream ID when making a connection, and not the downstream frequency.
Downstream frequency override
12.1 EC
Allows the Cisco uBR7100 series to change the downstream frequency for a cable interface, overriding the DOCSIS configuration file setting.
Downstream signal test commands
12.1 EC
Provides the following test capabilities: the cable downstream if-output command is enhanced with the following options to generate test signals on the downstream interface:
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The previous cable downstream if-output command has not changed and continues to output a standard modulated signal.
The no cable downstream if-output command has not changed; it stops all signal output and shuts down the interface.
Enhanced Rate Bandwidth Allocation (ERBA) Support for DOCSIS 1.0 Cable Modems
Cisco IOS release 12.3(13a)BC introduces Enhanced Rate Bandwidth Allocation (ERBA) support for DOCSIS 1.0 cable modems and the Cisco uBR7100 router. ERBA allows DOCSIS1.0 modems to burst their temporary transmission rate up to the full line rate for short durations of time. This capability provides higher bandwidth for instantaneous bandwidth requests, such as those in Internet downloads, without having to make changes to existing service levels in the QoS Profile.
This feature enables MSOs to set the DOCSIS 1.0 cable modems burst transmissions, with mapping to overriding DOCSIS 1.1 QoS profile parameters on the Cisco CMTS. DOCSIS 1.0 cable modems require DOCSIS 1.0 parameters when registering to a matching QoS profile. This feature enables maximum downstream line rates, and the ERBA setting applies to all cable modems that register to the corresponding QoS profile.
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DOCSIS 1.0 cable modems require DOCSIS 1.0 parameters when registering to a matching QoS profile. This feature enables the maximum downstream burst to be set in global configuration mode. The max-ds-burst setting applies to all cable modems that register to the corresponding QoS profile.
ERBA for DOCSIS 1.0 cable modems is supported with these new or enhanced commands or keywords in Cisco IOS release 12.3(13a)BC:
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Refer to Release Notes for Cisco uBR7100 Series for Cisco IOS Release 12.3 BC:
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Enhanced source address verification
12.1 EC
Prevents the spoofing of IP addresses by verifying that each upstream data packet comes from the CM known to be associated with the source IP address in the packet. The cable source-verify [dhcp] cable interface command specifies that DHCP lease query requests are sent to verify any unknown source IP address found in upstream data packets.
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EuroDOCSIS Support
12.1 EC
The Cisco uBR7111E and Cisco uBR7114E routers support the EuroDOCSIS Annex A standard with 8 MHz PAL or SECAM channel plan operation (similar to DAVIC/DVB ITU J.83 standard).
The EuroDOCSIS standard specifies a downstream 36.125 MHz interface, with a 8 MHz channel width and interleave factor of I=12, J=17. The card supports a downstream symbol rate of 6.592 Msymbols/sec at 64 QAM and 256 QAM. The downstream channel range supported is 85 to 860 MHz; the upstream channel range supported is 5 to 65 MHz.
Extended Upstream Frequency Ranges
12.2 BC
Cisco IOS Release 12.2(15)BC2 adds support for the extended upstream frequency range that is used in cable networks in Japan and other areas. This feature also clarifies the configuration of DOCSIS and EuroDOCSIS networks, so that the router shows only those upstream and downstream frequencies that are valid for each mode of operation.
A new CLI command, cable freq-range, was also added to support this feature on the Cisco uBR-MC16U/X and Cisco uBR-MC28U/X cards. For more information, see the Support for Extended Upstream Frequency Ranges, at the following URL:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122limit/122bc/122bc_15/mclcjfm.htmIntegrated Time of Day (ToD) server
12.1 EC
Allows the Cisco uBR7100 series to respond to ToD (RFC 868) queries from cable interfaces during the registration process.
Modem power enhancement adjustments for low SNR failures
12.1 EC
Allows Cisco uBR7100 series to better adjust when a CM seems to bounce—the CM requires frequent power adjustments in opposite directions. When this occurs, instead of making large power adjustments for each correction, the administrator can configure the Cisco uBR7100 series to calculate the average value of the power corrections before making power adjustments:
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The noise power adjustment method uses an averaging algorithm before sending any correction.
Vendor-Specific Information Field to Authorize Dynamic Service Requests
DOCSIS 1.1 cable modems can request additional bandwidth via the DOCSIS 1.1 dynamic services mechanism, by sending dynamic service add (DSA) and dynamic service change (DSC) messages (known collectively as DSX messages). By default, the CMTS grants these requests because a DOCSIS-compliant cable modem does not request services that would violate their provisioned service flows.
However, a cable modem that is using software that is not DOCSIS-compliant, or that is using software that has been hacked to include unauthorized changes that violate the DOCSIS specifications, could use dynamic services requests to obtain bandwidth that the user is not authorized to use. Users could also use dynamic services requests as part of a denial-of-service attack on the cable network.
To prevent this, Cisco IOS Release 12.2(15)BC2 supports including an optional vendor-specific information field (VSIF) in the DOCSIS configuration file to enable or disable DSX requests by the cable modem:
TLV = 43 (VSIF)
SubTLV 12, Length = 1
Value = 0, denies all DSX requests
Value = 1, allows all DSX requests
Refer to Cisco uBR7100 Series - Cisco IOS Release 12.2 BC:
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High Availability Features
N+1 HCCP Redundancy with Load Balancing
12.2 BC
Cisco IOS Release 12.2(15)BC2 supports configuring a cable interface for both load balancing and N+1 HCCP redundancy.
Intercept Features
Access List Support for COPS Intercept
12.3 BC
Cisco IOS Release 12.3(13a)BC introduces enhanced command-line interface for the Common Open Policy Service (COPS) feature.
To configure access control lists (ACLs) for inbound connections to all COPS listener applications on the Cisco CMTS, user the cops listeners access-list command in global configuration mode. To remove this setting from the Cisco CMTS, us the no forZzm of this command.
Refer to Release Notes for Cisco uBR7100 Series for Cisco IOS Release 12.3 BC:
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SII—Service Independent Intercept
12.3 BC
Cisco CMTS supports the Communications Assistance for Law Enforcement Act (CALEA) for voice and data. Cisco IOS Release 12.3(13a)BC introduces support for Service Independent Intercept (SII) on the Cisco uBR7100 CMTS. Cisco SII provides a more robust level of the lawful intercept (LI) options offered in the Packet Intercept feature. Cisco SII is the next level of support for judicially authorized electronic intercept, to include dial access, mobile wireless, tunneled traffic, and Resilient Transport Protocol (RTP) for voice and data traffic on the Cisco CMTS. SII on the Cisco CMTS includes these functions:
Packet intercept on specified or unspecified interfaces or ports, including port lists
Packet intercept on virtual interface bundles
Corresponding SNMP MIB enhancements for each of these functions, as intercept requests are initiated by a mediation device (MD) using SNMPv3
No new CLI commands are provided for this feature in Cisco IOS release 12.3(13a)BC.
Refer to Release Notes for Cisco uBR7100 Series for Cisco IOS Release 12.3 BC:
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IP Networking
ARP Filtering
12.2 BC
Cisco IOS Release 12.2(15)BC2 adds support for the cable arp filter command, which enables service providers to filter ARP request and reply packets, to prevent a large volume of such packets from interfering with the other traffic on the cable network. For more information, see the Cable ARP Filtering document, at the following URL:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122limit/122bc/122bc_15/cblarpfl.htmCisco IOS Release 12.2(15)BC2b introduces support for the ip-requests-filtered option, which was added to the show cable arp-filter command to display the specific Service IDs (SIDs) that are generating or forwarding a minimum number of ARP packets.
Refer to Cisco uBR7100 Series - Cisco IOS Release 12.2 BC:
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LLQ—Low Latency Queuing
12.3 BC
See "Upstream Schedule Modes (Optional)."
IP Routing
Basic wiretap support
12.1 EC
Provides support for a basic wiretap facility that the United States Federal Communications Assistance for Law Enforcement Act (CALEA) requires. This provides a mechanism such that user-to-user traffic can be captured.
The wiretap facility is based on the MAC address of the RF CPE device, so the wiretap facility can be used for either data or digitized higher priority connections. The feature is controlled by the new interface command—cable intercept—which requires a MAC address, an IP address, and a UDP port number as its parameters:
cable intercept[mac-address] ip-address udp-port
When activated, the Cisco uBR7100 series examines each packet for the desired MAC address. When a matching MAC address is found (for either the origination or destination endpoint), a copy of the packet is encapsulated into a UDP packet, which is then sent to the specified server at the given IP address and port.
Bridging Operation
12.1 EC
Performs forwarding of traffic on the basis of the MAC address between the cable and port adapter interfaces.
Cable modem multicast authentication (RADIUS)
12.1 EC
Permits RADIUS to be used to authenticate subscribers.
Cisco IOS router operating system
12.1 EC
Performs enhanced route filtering and translation to save network resources and prevent data from being broadcast to nodes that do not require it.
Integrated Routing and Bridging (IRB)
12.1 EC
Allows the Cisco uBR7100 series to use bridging on the cable and port adapter interfaces, while still providing access to routed networks, without having to use a separate external router.
Nonstop Forwarding (NSF) Awareness
12.2 BC
The Nonstop Forwarding (NSF) Awareness feature, introduced in Cisco IOS Release 12.2(15)T and inherited by Cisco IOS Release 12.2(15)BC1, allows customer premises equipment (CPE) routers that are NSF-aware to assist NSF-capable routers perform nonstop forwarding of packets.
The NSF Awareness feature is supported on three IP routing protocols—Border Gateway Protocol (BGP), Open Shortest Path First (OSPF), and Integrated Intermediate System-to-Intermediate System (IS-IS).
Refer to Cisco uBR7100 Series - Cisco IOS Release 12.2 BC:
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Per modem filters
(also known as per modem and per host access lists)12.1 EC
Allows the Cisco uBR7100 series to filter incoming packets from individual hosts or cable interfaces based on the source Media Access Control (MAC) or Internet Protocol (IP) address. This allows access lists to be specified on a per-interface and per-direction basis. The packets received from cable interfaces and individual hosts are filtered based on the cable interface or the host from which the packets are received.
Telco return
12.1 EC
Allows the Cisco uBR7100 series to register third-party DOCSIS-compliant telco return cable interfaces, based on the DOCSIS telco return specification. This allows the network to support two-way and telco return cable interfaces.
Transparent and IRB Bridging Operation
12.1 EC
Performs forwarding of traffic on the basis of the MAC address between the cable and port adapter interfaces.
Upstream Schedule Modes (Optional)
12.3 BC
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.
Refer to Release Notes for Cisco uBR7100 Series for Cisco IOS Release 12.3 BC:
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Management Features
Cable monitor
12.1 EC
Provides upstream and downstream sniffer capabilities.
Downstream Load Balancing Distribution with Upstream Load Balancing
12.3 BC
Cisco IOS Release 12.3(17b)BC4 introduces further enhancements to downstream load balancing, resulting in equalized upstream load balancing group members. This enhancement synchronizes the pending statistic between different cable interface line cards in the load balancing group.
This enhancement performs downstream load balancing that accounts for loads on upstream channels in the same upstream load balancing group, rather than on the basis of the entire downstream channel load. Prior Cisco IOS releases may not have distributed cable modems evenly over individual upstream channels, nor in a way that accounted for downstream and upstream segment loads that account for one another.
This enhancement applies when downstream load balancing occurs on a headend system with separate upstream load balancing segments; the upstream segments are spread over multiple downstreams segments. This enhancement provides an alternative downstream load balancing scheme that accounts and makes use of per-upstream loads rather than total downstream loads.
For additional information about Load Balancing on the Cisco CMTS, refer to the following documents on Cisco.com:
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http://www.cisco.com/en/US/products/hw/cable/ps2217/products_feature_guide09186a00801b17f2html
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Modem status display enhancements
12.1 EC
Enhancements support polling of CMs to obtain parameter and status information on an ongoing basis. Two new Cisco IOS commands are added to support the feature:
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Additional or changed show commands include:
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Subscriber Traffic Management 1.1
12.3 BC
Cisco IOS Release 12.3(9a)BC introduces support for Subscriber Traffic Management (STM) through Version 1.1 on the Cisco uBR7100 series universal broadband routers. STM 1.1 supports DOCSIS 1.1-compliant cable modems. The STM feature enables service providers to identify and control subscribers who exceed the maximum bandwidth allowed under their registered quality of service (QoS) profiles. STM 1.1 works with Network-Based Application Recognition (NBAR) and Access control lists (ACLs) to ensure full network performance to other network subscribers that abide by their service agreements. STM 1.1 also works in conjunction with the Cisco Broadband Troubleshooter 3.2 to support additional network management and troubleshooting functions in the Cisco CMTS.
STM 1.1 extends earlier STM functions to monitor a subscriber's traffic on DOCSIS 1.1 primary service flows and supports these additional features:
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For additional information about STM 1.1 and Cisco CBT 3.2, refer to the following document on Cisco.com:
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http://www.cisco.com/univercd/cc/td/doc/product/cable/trblshtr/cbt32/cbt32rn.htm
PacketCable and Voice Support Features
PacketCable
12.2 BC
Cisco IOS Release 12.2(15)BC2 supports PacketCable operations on the Cisco uBR-MC5X20S/U cable interface line cards on the Cisco uBR10012 router, and on the Cisco uBR-MC16U/X and Cisco uBR-MC28U/X cards on the Cisco uBR7246VXR router.
In addition, cable interfaces can be configured for both PacketCable operations and for N+1 HCCP redundancy. The debug packetcable hccp and show packetcable event commands have been added as part of this support.
Refer to Cisco uBR7100 Series - Cisco IOS Release 12.2 BC:
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Security Features
Dynamic Shared Secret
12.2 BC
The Dynamic Shared Secret feature provides service providers a way of providing higher levels of security for their Data-over-Cable Service Interface Specifications (DOCSIS) cable networks, by using randomized, single-use shared secrets to verify the DOCSIS configuration files that are downloaded to each cable modem. The Dynamic Shared Secret feature is enabled using the cable dynamic-secret interface configuration command.
The Dynamic Shared Secret feature automatically creates a unique DOCSIS shared secret on a per-modem basis, creating a one-time use DOCSIS configuration file that is valid only for the current session. This ensures that a DOCSIS configuration file that has been downloaded for one cable modem can never be used by any other modem, nor can the same modem reuse this configuration file at a later time.
This patent-pending feature is designed to guarantee that all registered modems are using only the quality of service (QoS) parameters that have been specified by the DOCSIS provisioning system for that particular modem at the time of its registration.
For information on the Dynamic Shared Secret feature, see the Configuring a Dynamic Shared Secret for the Cisco CMTS document, at the following URL:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122limit/122bc/122bc_15/ubrdmic.htmEncrypted Baseline Privacy key exchange
12.1 EC
Supports full DOCSIS 1.0 BPI specifications
40-bit and 56-bit Baseline Privacy Data Encryption Standard (DES)
12.1 EC
The Cisco uBR7100 series supports 40-bit and 56-bit encryption/decryption. When encryption/decryption is enabled, 56-bit is the default. If necessary, administrators can force the Cisco uBR7100 series to generate a 40-bit DES key, where the DES key that is generated and returned masks the first 16-bits of the 56-bit key to zero in software.
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Telco return RADIUS enhancements
12.1 EC
Enhancements provide additional authentication information, allowing an administrator to determine if a subscriber dialed a number that requires special billing arrangements (such as a toll-free number). If a telco return customer is being authenticated by a Terminal Access Controller Access Control System Plus (TACACS+) or RADIUS server, and if the number dialed by the CM is being redirected to another number for authentication, the system can include the original number in the information sent to the authentication server. The original number can be sent as a Cisco Vendor Specific Attribute (VSA) for TACACS+ servers and as RADIUS Attribute 93 (Ascend-Redirect-Number) for RADIUS servers.
Upstream address verification
12.1 EC
Supports verification of cable interface and PC addresses to ensure cable interface SID and MAC addresses are consistent; this helps ensure IP addresses are not spoofed. A PC behind a cable interface is assigned an IP address from the DHCP server. If a user on a second PC/cable interface statically assigns the same IP address to a PC, the Cisco uBR7100 series finds this case to help block the spoofing user. Using the CLI, administrators can determine the IP and MAC address of a given cable interface, and the SID number that shows the IP and MAC addresses of all devices learned in the cable interface MAC table. Using the service provider customer databases, administrators can cross reference the spoofing cable interface and PC and prevent usage.
SNMP Features and Enhancements
CISCO-NBAR-PROTOCOL-DISCOVERY-MIB
12.2(15)BC2
Cisco IOS Release 12.2(15)BC2 adds support for the CISCO-NBAR-PROTOCOL-DISCOVERY-MIB to the Cisco uBR7100 series and Cisco uBR7246VXR universal broadband routers. This allows service providers to use SNMP requests to configure and monitor the Network-Based Application Recognition (NBAR) feature.
For more information about NBAR, see the Network-Based Application Recognition and Distributed Network-Based Application Recognition document, at the following URL:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122t/122t8/dtnbarad.htmFor more information about the CISCO-NBAR-PROTOCOL-DISCOVERY-MIB, see the Network-Based Application Recognition Protocol Discovery Management Information Base document, at the following URL:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122t/122t15/ftpdmib.htmRF Interface Management Information Base (MIB)
12.1 EC
Improves object support for SNMP traps; traps are the mechanisms used to automatically send alarms for certain network events.
Service Class Setting Using SNMP
12.1 EC
Supports objects related to class of service.
Simple Network Management Protocol (SNMP) v3
12.1 EC
SNMP version 3 offers enhanced security features and increases interoperability. The implementation set of MIBs allows the SNMP manager to gather data such as system card descriptions, serial numbers, hardware and software revision levels, and slot location.
Support for RFC 2233
(RF Interface MIB)12.1 EC
Support DOCSIS OSSI Required Objects in RFC 2233 for the Cisco uBR7100 series.
Support for RFC 2665 for Cisco uBR7100 Series
12.1 EC
Support DOCSIS OSSI Required Objects in RFC 2665 for the Cisco uBR7100 series.
Spectrum Management Features
Dynamic upstream modulation
12.1 EC
Provides improved performance using proactive spectrum management functions.
Spectrum management
phases 1 and 212.1 EC
Supports the following spectrum management capabilities to specify the rules the system uses when hopping to another frequency when no clean frequency band is available:
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Testing, Troubleshooting and Diagnostic Features
Cisco Broadband Troubleshooter
12.3 BC
Cisco IOS Release 12.3(9a)BC introduces support for the Cisco Broadband Troubleshooter (CBT) Version 3.2 on the Cisco uBR7100 series universal broadband router. Multiple Service Operators (MSO) provide a variety of services such as TV, video on demand, data, and voice telephony to subscribers. Network Administrators and radio frequency (RF) technicians need specialized tools to resolve RF problems in the MSO's cable plant. Cisco Broadband Troubleshooter 3.2 (CBT 3.2) is a simple, easy-to-use tool designed to accurately recognize and resolve such issues.
The user can select up to three different cable modems (CMs) under the same CMTS or three different upstreams under the same CMTS. In addition, CBT 3.2 introduces the ability to display upstreams and cable modems combined (mixed) on the same trace window for monitoring and for playback.
Note
Refer to Release Notes for Cisco Broadband Troubleshooter Release 3.2:
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VLAN Features
Interswitch Link (ISL) bridging (noncable interfaces)
12.1 EC
Provides support for the ISL feature—Cisco protocol used to interconnect multiple routers and switches and maintain Virtual Local Area Network (VLAN) information as traffic is conveyed between the routers and switches.
Transparent LAN Service
12.2 BC
Cisco IOS Release 12.2(15)BC2 enhanced the existing support for Transparent Lan Services (TLS), which allows the Cisco CMTS to create Layer 2 tunnels for traffic to and from cable modems. This allows customers to create their own virtual local area network (VLAN) using any number of cable modems in multiple sites.
In addition to the ATM PVC Mapping, which was previously supported, Cisco IOS Release 12.2(15)BC2 added the ability to map a cable modem's MAC address to an IEEE 802.1Q VLAN on a specific Ethernet interface, so that all traffic from the cable modem is tagged with the specified VLAN ID. Service providers can now map cable modem traffic onto an ATM PVC or onto an Ethernet IEEE 802.1Q VLAN, depending on their customer's specific needs.
For more information on this service, see the Transparent LAN service over Cable document, at the following URL:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122limit/122bc/122bc_11/sidatmpv.htmVPN Features
TAG Switching Support on Cable Interfaces
12.1 EC
Supports enhancements made to tags placed on the fronts of packets that contain forwarding information used for making switching decisions for cable interfaces. A tag switching infrastructure combines advanced routing protocol capabilities to define IP VPNs by selectively advertising IP reachability information to just those subscribers within the same VPN or extranet on a cable interface.
WAN Optimization and Service Features
MLPPP Support
12.3 BC
The Cisco IOS Multilink Point-to-Point Protocol (MLPPP) feature is now supported for selected line cards and port adapters on the Cisco uBR7100 series, which share the same MLPPP code as the Cisco 7200 series. There is no new hardware or software for MLPPP in this release.
MLPPP combines one or more physical interfaces into a virtual "bundle" interface. The bandwidth of the bundle interface is equal to the sum of the component links' bandwidth. This allows service providers to make the step from T1 and E1 lines to affordable T3 and E3 speeds.
MLPPP is configured not on a cable interface, but on the T1/E1 link.
Refer to Release Notes for Cisco uBR7100 Series for Cisco IOS Release 12.3 BC:
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Per SID bandwidth request/grant counters
12.1 EC
Promotes better control of higher priority traffic, permitting per-SID bandwidth requests and grants. Profiles can be customized for scheduling parameters required at subscriber sites for the service offering. The show interface cx/0 upstream number command now supports a verbose option that displays:
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DOCSIS and CMTS Interoperability
The Cisco uBR7100 series routers support both the DOCSIS and EuroDOCSIS specifications, depending on the model. The Cisco uBR7111 and Cisco uBR7114 routers support DOCSIS operations, and the Cisco uBR7111E and Cisco uBR7114E routers support EuroDOCSIS operations. The following sections describe each standard in more detail.
DOCSIS Cable Plants
When using the DOCSIS specification, a cable plant modulates and demodulates data using 6-MHz downstream channels in the 54 to 860-MHz range and upstream channels in the 5 to 42 MHz range. The cable interface supports NTSC channel operation, using standard (STD), Harmonic Related Carrier (HRC), or Incremental Related Carrier (IRC) frequency plans conforming to EIA-S542.
NTSC uses a 6 MHz-wide modulated signal with an interlaced format of 25 frames per second and 525 lines per frame. NTSC is compatible with CCIR Standard M. PAL, used in West Germany, England, Holland, Australia, and several other countries.
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DOCSIS-compliant cable plants that support North American channel plans use ITU J.83 Annex B RF. Figure 1-1 illustrates a DOCSIS two-way and telco-return architecture.
Figure 1-1 DOCSIS Two-Way and Telco-Return Architecture
Larger cable companies typically have high-speed fiber backbones that carry Internet data, voice, and video between the following cable company facilities:
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The fiber backbone can be made up of OC-3 (155 Mbps) to OC-48 (2488 Mbps) Synchronous Optical Network (SONET) or Asynchronous Transfer Mode (ATM) rings. The backbone network can connect to other networks, including the Public Switched Telephone Network (PSTN), other cable system backbones, or to public Internet interconnect points that multiple ISPs use.
The CMTS Media Access Control (MAC) domain typically includes one or more downstream paths and one or more upstream paths. Depending on the CMTS configuration, the CMTS MAC domain can be defined to have its downstreams on one cable modem card with its upstreams on another card, or one or more CMTS MAC domains per cable modem card.
Cisco provides high-speed routers to route interactive traffic between the backbone and Ethernet in the headend internal network. Signaling protocols maintain the network intelligence needed to route traffic optimally, automatically building and maintaining routing tables to direct traffic and signal failures for rerouting in the network.
Border Gateway Protocol (BPG) typically operates between the cable operator's regional network and external networks, providing routing information exchange between different networks. The Open Shortest Path First (OSPF) protocol is used in regional networks usually. Cisco routers incorporate Cisco IOS software, which offers advanced software features, including quality of service (QoS), Weighted Fair Queuing (WFQ), and IP multicast.
The data path for DOCSIS networks is divided into the downstream (traffic sent from the CMTS to the CM) and the upstream (traffic sent from the CM to the CMTS). Because 90% of traffic in a typical Internet session is sent from the Internet to the user, the downstream is assigned the majority of the bandwidth allocated to each user.
A single downstream can support thousands of users, depending on their particular service needs. All of the users on a downstream might share the same upstream (as would be the case with a Cisco uBR7111 installation), or they might be split across several upstreams (as would be the case with a Cisco uBR7114 installation). For installations that have not been upgraded to two-way operations, the upstream can be provided through a telco-return connection, where the cable modem directs the upstream traffic through a modem that connects to the headend through the public telephone switched network (PTSN).
The following sections describe the downstream and upstream signals in more detail.
Downstream Signals
Downstream signals are modulated using QAM-64 or QAM-256 quadrature amplitude modulation, based on the cable interface card used, your cable plant, and the significance of the data. DOCSIS defines the messages and data types for CMTS to CM (or CM in an STB) communications. All CMs listen to all frames transmitted on the downstream channel on which they are registered and accept those where the destinations match the units themselves or the devices that each CM supports.
The Cisco uBR7100 series CMTS supports multicast groups using standard protocols such as Protocol Independent Multicast (PIM), Distance Vector Multicast Routing Protocol (DVMRP), and Internet Group Management Protocol (IGMP) to determine if multicast streams are to be forwarded to a prescribed downstream CM or STB, or a multicast routing peer.
The Cisco uBR7100 series software periodically sends MAC (Media Access Control) allocation and management messages—known as MAPs—to all CMs on the network, defining the transmission availability of channels for specific periods of time. The MAP rate is fixed—every 2 milliseconds.
Different transmission intervals are defined that associate an interval with a Service Identifier (SID). SIDs define the devices allowed to transmit, and provide device identification and class of service management. Software defines what type of transmission is allowed during the interval.
The CMTS system administrator typically assigns one or more SIDs to each CM, corresponding to the classes of service the CM requires. Each MAP is associated with a particular upstream channel. The SID concept supports multiple data flows and use of protocols such as Resource Reservation Protocol (RSVP) that allows IP backbone QoS features to be extended to the CMTS. The CMTS schedules the times granted for sending and receiving packets, and if defined, manipulates the type of service (ToS) field in the IP packet header to accommodate QoS.
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Tip
DOCSIS 1.0 extensions build intelligence into the MAP file, which the CMTS sends to voice-enabled CMs to address jitter and delay. The extensions support unsolicited grants which are used to create a constant bit rate-like stream between the CMTS and the CM, in contrast to typical data applications where CMs request grants from the CMTS before they can transmit upstream.
Upstream Signals
The upstream channel is characterized by many CMs (or CMs in STBs) transmitting to the CMTS. These signals typically operate in a burst mode of transmission. Time in the upstream channel is slotted.
The CMTS provides time slots and controls the usage for each upstream interval. The CMTS sends regular mappings of minislot structure in downstream broadcast MAP messages. The CMTS allocates contention broadcast slots that all CMs can use, and also allocates upstream minislots for unicast or noncontention data from specific CMs.
The CMTS allocates two basic types of contention slots on the upstream:
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The stream of initial ranging slots and bandwidth request minislots comprise two separate contention subchannels on the upstream. Cisco uBR7100 series software uses a "dynamic bandwidth-request minislots-per-MAP" algorithm to dynamically control the rate of contention slots for initial ranging and bandwidth-requests. The CMTS uses a common algorithm to vary backoff parameters that CMs use within each of the two upstream contention subchannels. The CMTS uses these algorithms to dynamically determine the initial ranging slots and bandwidth-request minislots to allocate on the slotted upstream.
When power is restored after a catastrophic power failure, a large number of CMs attempt to join the network simultaneously. This represents an impulse load on the initial ranging subchannel. The CMTS increases the frequency of initial ranging slots so that CMs can quickly join the network.
During high upstream data loads, the CMTS conserves the scarce upstream channel bandwidth resource and is more frugal in introducing upstream initial ranging slots. The CMTS schedules bandwidth-request minislots at low loads to provide low access delay. At high upstream loads, the CMTS reduces the number of contention-based request minislots in favor of data grants, while maintaining a minimum number of request slots.
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[no] cable insertion-interval [automatic [Imin [Imax]] in msecs
[no] cable upstream port number range backoff [automatic] | [start | end]
[no] cable upstream port number data-backoff [automatic] | [start | end]
Caution
The Cisco uBR7100 series equipment periodically broadcasts upstream channel descriptor (UCD) messages to all CMs. These messages define upstream channel characteristics that include upstream frequencies, symbol rates and modulation schemes, forward error correction (FEC) parameters, and other physical layer values.
Upstream signals are demodulated using quadrature phase shift keying (QPSK) or quadrature amplitude modulation (QAM). QPSK carries information in the phase of the signal carrier, whereas QAM uses both phase and amplitude to carry information.
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Automatic Provisioning of Cable Modems
A key component of DOCSIS networks is the ability to automatically provision each CM or STB as it comes online. To allow for this, the systems administrator creates DHCP and DOCSIS configuration files on the appropriate servers such that each CM or CM in an STB on the network, when initialized, can transmit a DHCP request, receive its IP address, obtain its TFTP and TOD server addresses, and download its DOCSIS configuration file (and updated software image, if needed).
The automatic provisioning scenario uses the following servers, which must be available to the CM through the cable interface:
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Using information in the DOCSIS configuration file, the CM can also use the TFTP server to download an updated software image or another configuration file (such as a Cisco IOS configuration file).
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DOCSIS 1.0-based CMs cannot connect to the broadband network until the following processes occur:
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The CMTS system administrator or customer service representative ensures appropriate databases are updated to activate and support the new subscriber account in the provisioning, billing, or network management systems in use for the network. Each CM or STB serial number and MAC address is typically stored in the billing and administrative system.
Initial and station maintenance management messages are sent to maintain communications between CMs and the CMTS. The following is a typical sequence of messages:
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EuroDOCSIS Cable Plants
The EuroDOCSIS standard builds on the DOCSIS protocol, adding support at the physical layer for PAL and SECAM channel plans. PAL uses a 625-line scan picture delivered at 25 frames per second where the color carrier phase definition changes in alternate scan lines. SECAM uses an 819 line scan picture that provides better resolution than PAL's 625-line and NTSC's 525-line resolutions.
The configuration and setup of EuroDOCSIS-based cable plants is similar to those of DOCSIS plants, except that they use the EuroDOCSIS J.112 (Annex A) standard, which uses a similar physical layer as Digital Audio Video Council/Digital Video Broadcast (DAVIC/DVB) J.83 Annex A networks. EuroDOCSIS operation permits full bandwidth utilization of the 8 MHz downstream channel in the 85-to-860 MHz range, allowing up to 50 Mbps throughput. EuroDOCSIS also offers an upstream frequency selection of 5 to 65 MHz, instead of the 5 to 42 MHz range used in DOCSIS networks.
Caution
A typical EuroDOCSIS architecture has four subsystems:
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Video sources are Motion Picture Experts Group (MPEG) encoded and then fed into an MPEG multiplexer that packs the MPEG video streams into a single stream. This stream is uplinked to a satellite and then downlinked to multiple headends, which then distribute the MPEG stream directly onto the HFC plant.
The STB receives signals from the cable network and displays them on a television. An STB with EuroDOCSIS CM functionality supports two-way interactivity. Inside the EuroDOCSIS STB are two tuners:
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EuroDOCSIS STB Support
Depending on the network configuration, servers that support Internet-enhanced video services—DTV application servers, user data servers, system management servers—and other tools and applications, are required to enable cable operators to deliver centrally managed services through STBs.
See the "Automatic Provisioning of Cable Modems" section. APIs need to be set up to allow EuroDOCSIS servers to communicate with the CSRC directory to obtain such information as IP addresses, user names, and subscription levels.
After registered subscribers receive a EuroDOCSIS-based STB, they can connect up the STB. Automatic configuration begins when the CM in the STB is detected and the CSRC DHCP server establishes IP connectivity and the basic IP configuration. As part of this initialization, the DHCP server transmits to the client STB, binding information for other resources such as TOD and TFTP servers.
When using this initial configuration, the DOCSIS CM uses TFTP to download its default DOCSIS configuration file, such as the DOCSIS options associated with the STB vendor subnet and CMTS. When minimally configured, the STB will register with the Cisco uBR7100 series router and create an associated object in the LDAP directory. The subscriber can then access the Cisco User Register web user interface to select one or more of the service packages the cable operator offers.
