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July 24, 2000
Part Number: OL-0385-03-Rev.B0
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Note You can find the most current Cisco IOS documentation on Cisco Connection Online (CCO). These electronic documents may contain updates and modifications made after this document was published. |
These release notes for the Cisco uBR924 Cable Access Router describe the enhancements provided in Cisco IOS Release 12.1(3a) T1. These release notes are updated as needed to describe new features, memory requirements, hardware support, software platform deferrals, and changes to the microcode or modem code and related documents.
For a list of software caveats that apply to Release 12.1(3a) T1, see the "Caveats" section and Caveats for Cisco IOS Release 12.1 T. The caveats document is updated for every maintenance release and is located on Cisco Connection Online (CCO) and the Documentation CD-ROM.
Use these release notes with Cross-Platform Release Notes for Cisco IOS Release 12.1 T located on CCO and the Documentation CD-ROM.
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Note Cisco IOS Release 12.1 T does not support the Cisco uBR904 Cable Access Router, which is an end-of-life (EOL) product. However, Cisco IOS Release 12.1 images do support the Cisco uBR904 router and include the current caveat fixes. |
These release notes describe the following topics:
The DOCSIS-based Cisco uBR924 Cable Access Router gives residential or small office/home office (SOHO) subscribers high-speed Internet or Intranet access. The Cisco uBR924 Cable Access Router supports both data traffic and packet voice and fax traffic via a shared two-way cable system and IP backbone network. The Cisco uBR924 Cable Access Router connects computers and other customer premises devices at a subscriber site to the service provider's cable, hybrid/fiber coax (HFC), and IP backbone network.
The Cisco uBR924 Cable Access Router is based on Data-Over-Cable Service Interface Specifications (DOCSIS) and interoperate with any bidirectional, DOCSIS-qualified Cable Modem Termination System (CMTS). The Cisco uBR924 Cable Access Router ships from the Cisco factory with a Cisco IOS software image stored in nonvolatile Flash memory that supports DOCSIS-compliant bridging data operations. The Cisco uBR924 Cable Access Router functions as a cable modem at the subscriber site to convey data communications on the cable television system.
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Note For information on new features and Cisco IOS commands supported by Release 12.1 T, see "New and Changed Information" section and "Related Documentation" section. |
Based on the feature licenses your company purchased, other Cisco IOS images can be downloaded from Cisco Connection Online (CCO). Special operating modes, based on your service offering and the practices in place for your network, can be supported for the Cisco uBR924 router, based on the available images in Cisco IOS Release 12.1(3a) T1. The Cisco uBR924 Cable Access Router can also function as an advanced router, providing wide area network (WAN) data connectivity in a variety of configurations.
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Note All Cisco uBR924 Cable Access Router images support DOCSIS Baseline Privacy Interface (BPI) encryption. BPI is subject to export restrictions. |
The Cisco uBR924 Cable Access Router features a single F-connector interface to the cable system, four RJ-45 (10BaseT Ethernet) hub ports, two RJ-11 Foreign Exchange Station (FXS) voice ports, one RJ-11 port for an optional backup analog telephone line connection, and one RJ-45 console port to connect to a laptop computer/console terminal for local Cisco IOS configuration. The Cisco uBR924 Cable Access Router supports voice and data Cisco IOS software images; available feature sets include Easy IP, Cisco Secure Integrated Software (Firewall Phase II), and IPsec encryption.
These release notes describe the Cisco uBR924 Cable Access Router for Cisco IOS Release 12.1(3a) T1, which is an early deployment (ED) release based on Cisco IOS Release 12.1. Early deployment releases contain fixes for software caveats and support for new Cisco hardware and software features.
Table 1 shows recent early deployment releases of the Cisco uBR924 Cable Access Router:
| ED Release | Maintenance Release | Additional Software Features | Availability | ||
|---|---|---|---|---|---|
Release 12.1 T | (3) | Now | |||
Release 12.1 T | (2) |
| Now | ||
Release 12.1 T | (1) |
| Now | ||
Release 12.0 XR1 | (7) |
| Now | ||
Release 12.0 XR | (7) |
| Now | ||
Release 12.0 T | (7) |
| Now | ||
Release 12.0 T | (5) |
| Now | ||
Release 12.0 XI1 | (4) |
| Now |
This section describes the system requirements for Cisco IOS Releases 12.1(3a) T1:
Table 2 lists the memory recommendations for each of the feature sets available for the Cisco uBR924 Cable Access Router in Cisco IOS Release 12.1(3a) T1. The image subset legend for Table 2 is as follows:
| Feature Set Matrix Term 1 | Image Name | Minimum Flash Memory | Minimum DRAM Memory | Runs From |
|---|---|---|---|---|
Home Office with Voice--Base image with Easy IP and Voice | ubr920-k1v4y5-mz | 4 MB Flash | 16 MB DRAM | RAM |
Value Telecommuter--Easy IP, Voice, and IPsec 56 | ubr920-k1v4y556i-mz | 4 MB Flash | 16 MB DRAM | RAM |
Performance Telecommuter-- Easy IP, Voice, and IPsec 3DES | ubr920-k1k2v4y5-mz | 4 MB Flash | 16 MB DRAM | RAM |
Value Small Office--Easy IP, Voice, FW2, and IPsec 56 | ubr920-k1o3v4y556i-mz | 4 MB Flash | 16 MB DRAM | RAM |
Performance Small Office-- Easy IP, Voice, FW2, and IPsec 3DES | ubr920-k1k2o3v4y5-mz | 4 MB Flash | 16 MB DRAM | RAM |
| 1L2TP is not supported in any Cisco IOS Release 12.1(3a) T1 images for the Cisco uBR924 Cable Access Router. 2FW--Firewall (Cisco Secure Integrated Software) |
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Note Cisco IOS Release 12.1 T supports fewer software images for the Cisco uBR924 Cable Access Router than Release 12.0 (which supported 14 separate images). The new simplified set of software images are a superset of the images supported in the previous releases, allowing for an easy upgrade path from Release 12.0 to Release 12.1. All of the images shown in Table 2 support both the Easy IP and Voice feature sets; the IPSec and Firewall feature sets are supported as shown. |
When using Cisco IOS Release 12.1(1) T or greater, the Cisco uBR924 Cable Access Router automatically supports the Cisco Cable Clock Card feature for voice traffic when the CMTS is a Cisco uBR7200 series universal broadband router with the Cisco Cable Clock Card feature.
If using DOCSIS concatenation with a 16 QAM symbol rate, the CMTS must be configured for Unique Word 16 in the preamble for both short and long data burst profiles. On the Cisco uBR7200 series universal broadband routers, use the cable modulation-profile global configuration command and specify uw16 for both the long and short modulation profiles. See caveats CSCdp76415 and CSCdp92139 for more detail.
Cisco IOS Release 12.1 T images support the Cisco DOCSIS 1.0+ Extensions, which include dynamic multi-SID assignment and concatenation. To use the dynamic multi-SID and concatenation features, both the Cisco uBR924 router and the CMTS router must have support them. If you are using the Cisco uBR7200 series headend equipment as the CMTS router, Cisco IOS Release 12.0(7) XR, Release 12.1(1) T, or greater is required on both the Cisco uBR924 Cable Access Router and the CMTS router to ensure these features are activated.
To configure the Cisco uBR924 Cable Access Router to support multiple classes of service, use either the Cisco Subscriber Registration Center (CSRC) tool or the configuration file editor of your choice. DOCSIS configuration files can contain multiple classes of service (CoS) to support voice. The first CoS is used for data (and voice if no other CoS is defined), and up to three additional classes of service can be defined to give higher priority for voice traffic.
To use IPsec encryption, both the Cisco uBR924 Cable Access Router and the destination endpoint must both support IPsec encryption and be configured for the same encryption policy. The endpoint is typically an IPsec gateway such as a peer router, PIX firewall, or other device that can be configured for IPsec. (The CMTS does not need to support IPsec encryption unless it is desired that the CMTS act as an IPsec gateway.)
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Note The IPsec feature set encrypts traffic sent between endpoints, such as between two Cisco uBR924 Cable Access Routers, to protect traffic sent across the Internet and other unprotected networks. The DOCSIS BPI feature encrypts traffic on the cable interface, between the Cisco uBR924 Cable Access Router and the CMTS. To use BPI encryption, both the Cisco uBR924 Cable Access Router and the CMTS must support and enable BPI encryption. |
When using a voice-enabled Cisco IOS Release 12.1 image, the Cisco uBR924 Cable Access Router can packetize and transport voice in compliance with the H.323 protocol. H.323v2 is integrated in Cisco gatekeeper/gateway products, such as the Cisco 2600 series and Cisco 3600 series, using Cisco IOS Release 12.0(5) T. The gatekeeper must be running Cisco IOS Release 12.0(5) T or greater to support registration of the full E.164 address for each Cisco uBR924 Cable Access Router voice port.
The Cisco uBR924 Cable Access Router also supports the Simple Gateway Control Protocol (SGCP) when using voice-enabled Cisco IOS Release 12.1 images. SGCP is an alternative to the H.323 protocol that provides signaling and feature negotiation via a remote Call Agent (CA). SGCP eliminates the need for a dial plan mapper. It also eliminates the need for static configuration on the router to map IP addresses to telephone numbers because this function is provided by the remote CA.
The Cisco uBR924 Cable Access Router contains:
To determine the version of Cisco IOS software running on your Cisco uBR924 Cable Access Router, log into the Cisco uBR924 Cable Access Router and enter the show version EXEC command:
For the Cisco uBR924 Cable Access Router:
router# show version Cisco Internetwork Operating System Software IOS (tm) 920 Software (ubr920-k1v4y5-mz), Version 12.1(3a) T1, RELEASE SOFTWARE
For technical information about upgrading to a new software release, see Cisco IOS Upgrade Ordering Instructions on CCO located at:
http://www.cisco.com/warp/public/620/6.html
For other information about upgrading to Cisco IOS Release 12.1, see the product bulletin Cisco IOS Software Release 12.1 Upgrade Paths and Packaging Simplification on CCO at:
Service & Support: Software Center: Cisco IOS Software: Product Bulletins: Software
Under Cisco IOS 12.1, click Cisco IOS Software Release 12.1 Ordering Procedures and Platform Support
Cisco IOS software is packaged in feature sets consisting of software images--depending on the platform. Each feature set contains a specific set of Cisco IOS features.
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Caution Cisco IOS images with strong encryption (including, but not limited to, 168-bit [3DES] data encryption feature sets) are subject to United States government export controls and have limited distribution. Strong encryption images to be installed outside the United States may require an export license. Customer orders may be denied or subject to delay due to United States government regulations. When applicable, the purchaser/user must obtain local import and use authorizations for all encryption strengths. Contact your sales representative or distributor for more information, or send an e-mail to export@cisco.com. |
Table 3 lists the voice and data software images by feature sets for the Cisco uBR924 Cable Access Router. This table uses the following conventions:
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Note These feature set tables might contain a selected list of features. These tables might not be cumulative--nor do they list all the features in each image. |
| Software Images by Feature Set Matrix Term | |||||
|---|---|---|---|---|---|
| Features | Home Office with Voice | Value Telecommuter | Performance Telecommuter | Value Small Office | Performance Small Office |
Baseline Privacy Interface (BPI) Encryption | Yes | Yes | Yes | Yes | Yes |
Baseline Privacy Interface (BPI) MIB | Yes | Yes | Yes | Yes | Yes |
Cable Device MIB (RFC 2669) | Yes | Yes | Yes | Yes | Yes |
Cable Monitor | Yes | Yes | Yes | Yes | Yes |
Cisco Secure Integrated Software (Firewall) | No | No | No | Yes | Yes |
Cisco Standard MIBs | Yes | Yes | Yes | Yes | Yes |
Cisco Voice MIBs | Yes | Yes | Yes | Yes | Yes |
Configurable H.225 Timers | Yes | Yes | Yes | Yes | Yes |
DHCP Proxy Support | Yes | Yes | Yes | Yes | Yes |
DOCSIS 1.0+ Extensions (Dynamic multi-SID assignment and concatenation) | Yes | Yes | Yes | Yes | Yes |
DOCSIS-Compliant Bridging | Yes | Yes | Yes | Yes | Yes |
Easy IP | Yes | Yes | Yes | Yes | Yes |
Ecosystem Gatekeeper Interoperability Enhancements | Yes | Yes | Yes | Yes | Yes |
HSRP Support for ICMP Redirect | Yes | Yes | Yes | Yes | Yes |
H.323v2 Protocol | Yes | Yes | Yes | Yes | Yes |
H.323 Support for Virtual Interfaces | Yes | Yes | Yes | Yes | Yes |
IPsec Encryption with 56-bit DES | No | Yes | Yes | Yes | Yes |
IPsec Encryption with Triple DES (3DES) | No | No | Yes | No | Yes |
Layer 2 Tunneling Protocol (L2TP)1 | No | No | No | No | No |
Media Gateway Control Protocol (MGCP) Residential Gateway (RGW) Support | Yes | Yes | Yes | Yes | Yes |
RFC 2233 Support | Yes | Yes | Yes | Yes | Yes |
Radio Frequency Interface MIB (RFC 2670) | Yes | Yes | Yes | Yes | Yes |
Routing (RIP V2) | Yes | Yes | Yes | Yes | Yes |
Secure Shell (SSH)--56-bit encryption | Yes | Yes | Yes | Yes | Yes |
Secure Shell (SSH)--3DES encryption | No | No | Yes | No | Yes |
Simple Gateway Control Protocol (SGCP) | Yes | Yes | Yes | Yes | Yes |
XGCP MIB | Yes | Yes | Yes | Yes | Yes |
| 1The L2TP feature set is not supported in any Cisco IOS Release 12.1(3a) T1 images for the Cisco uBR924 Cable Access Router. |
The following sections list the new hardware and software features supported by the Cisco uBR924 Cable Access Router.
Cisco IOS Release 12.1(3a) T1 does not contain any new hardware features for the Cisco uBR924 Cable Access Router.
The following new software features are supported by the Cisco uBR924 Cable Access Router for Release 12.1(3a) T1.
Cisco IOS Release 12.1(3a) T1 for Cisco uBR900 series Cable Access Routers adds support for the ip address dhcp command on the cable interface. Previous releases used the ip address negotiated command for this purpose, but this command is now reserved for serial interfaces. This change is cosmetic only and does not change how the router obtains its IP address. See "IP Address Negotiation" section for additional information.
The HSRP Support for ICMP Redirects feature enables Internet Control Message Protocol (ICMP) redirection on interfaces configured with the Hot Standby Router Protocol.
When running HSRP, it is important to prevent hosts from discovering the interface (or real) MAC addresses of routers in the HSRP group. If a host is redirected by ICMP to the real MAC address of a router, and that router later fails, then packets from the host will be lost. Previously, ICMP redirect messages were automatically disabled on interfaces configured with HSRP.
This feature now enables ICMP redirects on interfaces configured with HSRP. This functionality works by filtering outgoing ICMP redirect messages through HSRP, where the next-hop IP address may be changed to an HSRP virtual IP address.
Cisco IOS Release 12.1(3a) T1 for the Cisco uBR924 Cable Access Router supports version 0.1 of the Media Gateway Control Protocol (MGCP), a proposed IETF voice control protocol that is intended to eventually supersede the existing SCGP 1.1 protocol. The MGCP 0.1 and SGCP 1.1 protocols have been merged on the Cisco uBR924 router so that the router can respond efficiently to either protocol.
The Cisco uBR924 Cable Access Router functions as a Residential Gateway (RGW), providing an interface between analog FXS phone or fax systems and the Voice over IP (VoIP) network. The RGW uses a Trunking Gateway (TGW) to contact the call agent, which in turn provides access to the public telephone switched network (PTSN).
The Cisco uBR924 Cable Access Router supports both call waiting and caller ID when using either MGCP or SGCP for call control. Each of the two voice ports on the Cisco uBR924 router can be configured with the IP address for a default call agent. SNMP management of both the MGCP and SNMP protocols is provided by a single MIB (XGCP-MIB).
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Note This feature is described in detail in the Media Gateway Control Protocol Version 12.1.3 T feature module, available on CCO and the Documentation CD-ROM. |
Cisco IOS Release 12.1(3a) T1 enhances the router's support for the Secure Shell (SSH) protocol, which was introduced in Cisco IOS Release 12.1(1) T (see the "Secure Shell Server Support" section). SSH connections use encryption and user authentication to establish a secure communications channel over an insecure network, such as the Internet.
In Cisco IOS Release 12.1(3a) T1, SSH support now includes the following features:
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Note For configuration and other information, see the Secure Shell Version 1 Client feature module, available on CCO and the Documentation CD-ROM. |
Cisco IOS Release 12.1(2) T does not contain any new hardware features for the Cisco uBR924 Cable Access Router.
The following new software features are supported by the Cisco uBR924 Cable Access Router for Release 12.1(2) T. For more information on these features, see the documentation listed in the "Related Documentation" section.
In previous Cisco IOS releases, the H.225 TCP connection timeout timer was fixed at 15 seconds. Cisco IOS Release 12.1(2) T adds the ability to configure this timer to a value between 1-30 seconds, or to disable it entirely.
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Note For more information on this feature, see the Configuring the Configurable Timers in H.225 feature module, available on CCO and the Documentation CD-ROM. |
This feature enhances the existing Ecosystem Gatekeeper Interoperability Enhancements feature to improve the ability of voice gateways to move between gatekeepers upon a failure or an outage. In addition to the existing features, phase 2 adds support for the alternate gatekeeper field (altGKInfo) to the admission rejection (ARJ) message. This allows a gateway to move between gatekeepers during the admission request (ARQ) phase.
Phase 2 of this feature is introduced in Cisco IOS Release 12.1(2) T.
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Note For more information on this feature, see the Ecosystem Gatekeeper Interoperability Enhancements, Phase 2 feature module, available on CCO and the Documentation CD-ROM. |
Cisco IOS Release 12.1(2) T for the Cisco uBR924 Cable Access Router introduces a new interface command to control the IP address used for outgoing H.323 VoIP traffic:
The h323-gateway voip bind command can be used with any interface, but its primary use is with the Cisco uBR924 router's Ethernet interface when configuring a virtual private network (VPN). In this configuration, the h323-gateway voip bind command configures the router so that VoIP traffic is sent and received using the IP address of the Ethernet interface (as opposed to the default behavior, which is to use the IP address of the default outgoing interface, which is the cable interface).
The h323-gateway voip bind command allows the enterprise network to maintain the H.323 gatekeeper and gateway in the enterprise network's address space. Without the h323-gateway voip bind command, outgoing voice traffic uses the IP address of the cable interface. This requires that the H.323 gatekeeper and gateway be maintained in the cable service provider's address space, which is not desirable if the enterprise needs to control the voice network and VPN configuration.
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Note The h323-gateway voip bind command should be used only when the Cisco uBR924 Cable Access Router is operating in routing mode. This command has no effect when the router is operating in DOCSIS bridging mode. |
This feature was tracked as caveat CSCdp11931, and it was introduced in Cisco IOS Release 12.1(2) T.
Cisco IOS Release 12.1(2) T updates the IF-MIB MIB with support for RFC 2233, which obsoletes the previous RFC 1573. This change adds the ifCounterDiscontinuityTime attribute and changes the ifTableLastChange attribute.
In addition, this feature adds support for RFC 2233-compliant link up and link down traps. By default, link up and link down traps are implemented as given in the CISCO-IF-CAPABILITY.my MIB. To generate link up and link down traps as defined by RFC 2233, use the snmp-server trap link ietf global configuration command.
This feature was tracked as caveats CSCdp41317 and CSCdp55546, and it is introduced in Cisco IOS Release 12.1(2) T.
Cisco IOS Release 12.1(1) T does not contain any new hardware features for the Cisco uBR924 Cable Access Router.
The following new software features are supported by the Cisco uBR924 Cable Access Router for Release 12.1(1) T. For more information on these features, see the documentation listed in the "Related Documentation" section.
The Cable Monitor is a web-based diagnostic tool to display the current status and configuration of the Cisco uBR924 router. The Cable Monitor can also be used when the cable network is down, providing an easy way for subscribers to provide necessary information to service technicians and troubleshooters.
The Cable Monitor is introduced in Cisco IOS Release 12.1(1) T.
When using Cisco IOS Release 12.1(1) T or greater, the Cisco uBR924 Cable Access Router automatically supports the Cisco Cable Clock Card feature for voice traffic when the CMTS is a Cisco uBR7200 series universal broadband router with the Cisco Cable Clock Card feature. This feature can enhance reliability in a voice network and reduce delay and jitter in the voice traffic.
In addition to the other QoS features, DOCSIS 1.1 supports a number of features that are required for the delivery of high quality voice traffic. To use these features before the DOCSIS 1.1 specification is finalized, Cisco has created the DOCSIS 1.0+ extensions that contain the most important of these features:
The DOCSIS 1.0+ features are introduced in Cisco IOS Software Release 12.0(7) XR and 12.1(1) T.
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Note Both the Cisco uBR924 Cable Access Router and the CMTS must support the dynamic multi-SID and concatenation features for them to be used on the cable network. If you are using the Cisco uBR7200 series universal broadband router as the CMTS, Cisco IOS Release 12.0(7) XR or 12.1(1) T (or later) is required on both the Cisco uBR924 and Cisco uBR7200 series routers to use these features. |
The DHCP Proxy Support feature helps to automate the configuration of the Cisco uBR924 Cable Access Router in two situations:
When configured for DHCP Proxy Support, during startup the Cisco uBR924 Cable Access Router sends a proxy DHCP request to the DHCP server using the Ethernet interface's MAC address. The DHCP server replies with a second IP address that the router assigns to either the Ethernet interface or to the NAT pool, depending on which option was specified.
The Ecosystem Gatekeeper Interoperability Enhancements feature improves the ability of voice gateways to move between gatekeepers upon a failure or an outage. Currently, gateways can be configured to switch from their primary gatekeeper to an alternate gatekeeper if a failure or outage occurs.
However, moving gateways from one gatekeeper to another can create an imbalance in the number of gateways registered to each gatekeeper. The Ecosystem Gatekeeper Interoperability Enhancements feature helps to restore the balance by moving some of the gateways back to their proper gatekeepers after the outage has been corrected.
This feature adds support for the alternate gatekeeper field (altGKInfo) to the gatekeeper rejection (GRJ) and registration rejection (RRJ) messages. This allows a gateway to move between gatekeepers during the gatekeeper request (GRQ) and registration request (RRQ) phases.
This feature is introduced in Cisco IOS Release 12.1(1) T.
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Note For more information on this feature, see the Ecosystem Gatekeeper Interoperability Enhancements feature module, available on CCO and the Documentation CD-ROM. |
Cisco IOS Release 12.1(1) T adds a number of H.323v2 features for voice support:
This feature is introduced in Cisco IOS Release 12.0(7) XR and Release 12.1(1) T.
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Note For information about these features, see H.323 Version 2 Support , available on CCO at http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120t/120t5. |
The Cisco uBR924 router supports the Secure Shell (SSH) Version 1 protocol, which allows network administrators to make a secure Telnet connection with the router. SSH provides for authentication and encryption at the application layer, providing a secure connection even when BPI or IPsec authentication and encryption are not used at the network layer.
By default, the SSH feature uses 56-bit DES encryption. Higher security 168-bit 3DES encryption is available when using Cisco IOS images that support 3DES IPsec encryption. (The SSH client must also support the same level of encryption.)
SSH client server is introduced in Cisco IOS Release 12.1(1) T.
Cisco IOS Release 12.1(1) T adds support for RFC 2669 and RFC 2670 to the DOCS-CABLE-DEVICE-MIB and DOCS-IF-MIB MIBs, respectively.
The following new hardware features are supported by the Cisco uBR924 Cable Access Router for Release 12.1(1):
The following new software features are supported by the Cisco uBR924 Cable Access Router for Release 12.1(1):
This section describes warnings and cautions about using Cisco IOS Release 12.1(3a) T1 software.
The Cisco uBR924 Cable Access Router interoperates with DOCSIS cable networks. Cisco IOS Release 12.1 T does not support bridging traffic across a non-DOCSIS cable network.
To comply with DOCSIS requirements that restrict access to commands that change DOCSIS parameters, Cisco IOS Release 12.1(2) T has removed a number of commands from the CLI. These commands are now reserved exclusively for DOCSIS use. See the description of caveat CSCdr32984 for more details.
GRE IP tunnels cannot be built between two Cisco uBR924 Cable Access Routers because GRE IP tunnels are not supported in any Cisco IOS image for the Cisco uBR924 Cable Access Routers. IPsec tunnels, however, are supported when using Cisco IOS images that support IPsec encryption.
The DOCSIS specifications require that a cable modem obtain its IP address at power-on or reset from a DHCP server that is available through the cable interface. For this reason, the Cisco uBR924 Cable Access Router defaults to a configuration that uses the ip address dhcp command for the cable interface. It is not possible to override this setting by specifying a specific static IP address; to assign a static IP address to the Cisco uBR924 router, configure the DHCP server so that it assigns the desired IP address on the basis of the unit's MAC address.
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Note The ip address negotiated command cannot be used on the cable interface because this command is reserved exclusively for the serial interface. However, in Cisco IOS Release 12.1(3a) T1 when the ip address dhcp command is used for cable interfaces, the configuration files still show the ip address negotiated command, which can generate an "invalid input" error during boot. This is only a cosmetic issue and does not affect the unit's functionality. See the description of caveat CSCdr61697, for more information. |
To enable BPI encryption, the Cisco uBR924 Cable Access Router must use a Cisco IOS image that supports BPI encryption. If the router's current software image does not support BPI encryption (or if the current software image is corrupted), you must disable BPI encryption in the DOCSIS configuration file and reset the router before you will be able to download a new software image.
Access lists 100 and 101 should never be manually configured on the Cisco uBR924 Cable Access Router. Configuring these access lists with Cisco IOS Release 12.1 T images that support any form of IPsec encryption can crash the router. Use any access lists 102 through 199 instead. See the description of caveats CSCdr45850 and CSCdr46128 for more information.
The MAX CPE parameter in a Cisco uBR924 Cable Access Router's DOCSIS configuration file determines how many PCs (or other CPE devices) are supported by the Cisco uBR924 Cable Access Router. The default value for the MAX CPE parameter is 1, which means only one PC can be connected to the Cisco uBR924 Cable Access Router.
The DOCSIS 1.0 specification states that a CMTS cannot age-out MAC addresses for CPE devices, so the first PC that is connected to the Cisco uBR924 Cable Access Router is normally the only one that the CMTS recognizes as valid. If a subscriber replaces an existing PC or changes its network interface card (NIC) to one that has a different MAC address, the CMTS will refuse to let the PC come online because this would exceed the maximum number of CPE devices specified by the MAX CPE parameter. A similar thing would happen if a user decides to move a PC from one Cisco uBR924 router to another.
To allow a subscriber to replace an existing PC or NIC, the following workarounds are possible:
The reset switch on the back panel of the Cisco uBR924 Cable Access Router is recessed to prevent accidental resets of the router. To depress the switch, use a blunt object, such as a pen or pencil point; do not use a sharp object, such as a knife or awl, because this could damage the switch and the router's circuitry.
This section contains important information about using Cisco IOS Release 12.1(3a) T1 software.
In Cisco IOS Release 12.1(2) T and above, the docsDevCpeIpMax attribute defaults to -1 instead of the previous default of 1. This attribute controls the maximum number of CPE devices that can pass traffic through the router from its Ethernet interface as follows:
CPE IP address filtering is done as part of the following process:
1. MAC address filtering--Packets are filtered on the basis of the CPE device's MAC address. This is controlled by the value of the MAX CPE parameter, which is set in the DOCSIS configuration file.
2. Link Level Control (LLC) filtering--Packets are filtered on the basis of the packet's protocol. This is controlled by the docsDevFilterLLCTable table.
3. CPE IP address filtering--Packets are filtered on the basis of the CPE device's IP address, as controlled by the docsDevCpeIpMax attribute and docsDevFilterCpeTable table.
4. Access list filtering--Packets are filtered on the basis of access lists. IP filtering is controlled by the docsDevFilterIpTable table, and SNMP access filters are controlled by the docsDevNmAccessTable.
See the DOCS-CABLE-DEVICE-MIB.my MIB for more information on the attributes and tables listed above.
By default, the Cisco uBR900 series Cable Access Router enables its onboard TCP/IP "finger" server to allow remote users to query the number and identities of any users who are logged in to the router. Unless your network operations center (NOC) requires this service, it should be disabled to prevent denial of service attacks that access the finger server's well-known port (TCP port 79). To disable the finger server, include the no service finger command in the Cisco IOS configuration file that the router downloads at initial power-on.
Troubleshooting Tips for the uBR924 Cable Access Router, page 15, indicates:
The correction should read:
The Cisco uBR924 Cable Access Router supports the following categories of MIBs:
The Cisco uBR924 Cable Access Router supports the Cable Device MIB, which is defined by RFC 2669 and describes DOCSIS-compliant cable modems and CMTS. The Cable Device MIB records statistics related to the configuration and status of the cable modem. Statistics include an events log and device status. The following list details the components of the Cable Device MIB:
The Cable Device MIB is very similar to the RFI MIB in that both allow access to statistics; they are different in that the Cable Device MIB reports statistics on the cable modem, and the RFI MIB reports statistics on the radio frequency transmissions over the cable television line.
The Cisco uBR924 Cable Access Router supports the Cisco Standard MIBs, which consist of the following components:
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Note The Cisco Management Information Base (MIB) User Quick Reference publication is no longer published. For the latest list of MIBs supported by Cisco, see the Cisco Network Management Toolkit on Cisco Connection Online (CCO). From the CCO home page, click on this path: Service & Support: Software Center: Network Mgmt Products: Cisco Network Management Toolkit: Cisco MIB |
The Cisco uBR924 Cable Access Router supports the Cisco Voice MIBs are supported, which consist of the following components:
The Cisco uBR924 Cable Access Router supports the Radio Frequency Interface (RFI) MIB. The RFI MIB module is defined in RFC 2670 and describes DOCSIS-compliant radio frequency interfaces in cable modems and CMTS. On the cable modem, RFI MIB entries provide:
The RFI MIB includes tables describing both the CMTS and the cable modem side of the cable interface. All cable modem tables are implemented.
With IPsec, data can be transmitted across a public network without fear of observation, modification, or spoofing. This enables applications such as VPNs, extranets, and remote user access.
IPsec services are similar to those provided by Cisco Encryption Technology, a proprietary Cisco security solution. However, IPsec provides a more robust security solution, and is standards based.
The Cisco uBR924 Cable Access Router supports the Simple Gateway Control Protocol (SGCP) and Media Gateway Control Protocol through a single MIB (XGCP-MIB ). This MIB supports configuration, performance, and fault management of the SGCP and MGCP interfaces.
The key attributes of this MIB are as follows:
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Note For complete details on this MIB, see the XGCP-MIB.my file on the CCO MIB web site. |
Table 4 shows the cable-specific MIBs that are supported on the Cisco uBR924 Cable Access Router. This table also provides a brief description of each MIB's contents and the Cisco IOS software release in which the MIB was initially functional--earlier releases might have had unsupported prototype versions of the MIB; later releases might have added new attributes and functionality.
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Note The names given in Table 4 are the filenames for the MIBs as they exist on Cisco's FTP site (ftp://ftp.cisco.com/pub/mibs/ or http://www.cisco.com/public/mibs/index.htm). Most MIBs are available in both SNMPv1 and SNMPv2 versions; the SNMPv1 versions have V1SMI as part of their filenames. Also see the Cisco MIBs home page at http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml. |
| MIB Filename | Description | Release | ||
|---|---|---|---|---|
This module specifies the Structure of Management Information (SMI) for SNMPv2, as defined in RFC 1902. | 12.0(4) XI | |||
This module defines the textual conventions as specified in pages 4, 10-11 of RFC 854. | 12.0(4) XI | |||
This module specifies the Structure of Management Information (SMI) for Cisco's enterprise MIBs. | 12.0(4) XI | |||
This module defines the textual conventions used in Cisco's enterprise MIBs. | 12.0(4) XI | |||
This module describes generic objects for the Layer 3 network interface sublayers. This MIB is an updated version of MIB-II's if table, and incorporates the extensions defined in RFC 2233. | 12.0(4) XI RFC 2233 support: 12.1(2) T | |||
This module describes the spectrum management flap list attributes. | 12.0(5) T1 | |||
This module describes the DOCSIS-compliant Radio Frequency (RF) interfaces in cable modems and cable modem termination systems, as described in RFC 2670. | 12.0(4) XI RFC 2670 support: 12.1(1) T | |||
This module describes the attributes for the DOCSIS-specified Baseline Privacy Interface (BPI) on cable modems and the CMTS. | 12.0(5) T | |||
This module extends the DOCSIS standard RFI MIB (DOCS-IF-MIB) with Cisco-specific extensions, such as QoS attributes and connection status and other information regarding the cable modems and CPE devices supported by the CMTS.
| partial support: full support: | |||
This module was previously known as the CABLE-DEVICE-MIB and contains cable-related objects for DOCSIS-compliant cable modems, as specified in RFC 2669 . | 12.0(4) XI RFC 2669 support: |
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Note Because of interdependencies, the MIBs must be loaded in the order given in the table. |
A number of Cisco-provided MIBs have been replaced with more scalable, standardized MIBs; these MIBs have filenames that start with "OLD" and first appeared in Cisco IOS Release 10.2. The functionality of these MIBs has already been incorporated into replacement MIBs, but the old MIBs are still present to support existing Cisco IOS products or NMS applications. However, because the deprecated MIBs will be removed from support in the future, you should update your network management applications and scripts to refer to the table names and attributes that are found in the replacement MIBs.
Table 5 shows the deprecated MIBs and their replacements. In most cases, SNMPv1 and SNMPv2 replacements are available, but some MIBs are available only in one version. A few of the deprecated MIBs do not have replacement MIBs; support for these MIBs will be discontinued in a future release of Cisco IOS software.
| Deprecated MIB | Replacement MIBs | |
|---|---|---|
| SNMPv1 MIB | SNMPv2 MIB | |
-- | ||
-- | ||
-- | -- | |
-- | -- | |
-- | ||
(Compilation of other OLD* MIBS) | ||
-- | -- | |
-- | -- | |
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Note Some of the MIBs listed in Table 5 represent feature sets that are not supported on the Cisco uBR924 Cable Access Router. |
Caveats describe unexpected behavior in Cisco IOS software releases. Severity 1 caveats are the most serious caveats; severity 2 caveats are less serious.
This section contains open and resolved caveats for Cisco IOS Release 12.1(3a) T1. All caveats in Release 12.1 are also in Release 12.1(3a) T1.
For information on caveats in Cisco IOS Release 12.1, see Caveats for Cisco IOS Release 12.1, which lists severity 1 and 2 caveats, and is located on CCO and the Documentation CD-ROM.
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Note If you have an account with CCO, you can use Bug Navigator II to find caveats of any severity for any release. To reach Bug Navigator II, go to CCO and press Login. Then go to Software Center: Cisco IOS Software: Cisco Bugtool Navigator II. Another option is to go to http://www.cisco.com/support/bugtools (you must have an account on CCO to access this site). |
All the caveats listed in this section are open in Release 12.1(3a) T1:
All the caveats listed in this section are closed or resolved in Release 12.1(3a) T1:
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no ip http server
The following sections describe the documentation available for the Cisco uBR924 Cable Access Router. These documents consist of hardware and software installation guides, Cisco IOS configuration and command references, system error messages, feature modules, and other documents.
Most documentation is available as printed manuals or electronic documents, except for feature modules and select manuals, which are available online on CCO and the Documentation CD-ROM.
Use these release notes with these documents:
The following documents are specific to Release 12.1 and are located on CCO and the Documentation CD-ROM:
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Note If you have an account with CCO, you can use Bug Navigator II to find caveats of any severity for any release. To reach Bug Navigator II, go to CCO and press Login. Then go to Software Center: Cisco IOS Software: Cisco Bugtool Navigator II. Another option is to go to http://www.cisco.com/support/bugtools (you must have an account on CCO to access this site). |
These documents are available for the Cisco uBR924 Cable Access Router on CCO and the Documentation DC-ROM:
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Note The Cisco uBR924 Cable Access Router Installation and Configuration Guide is still available on CCO but has been obsoleted by the hardware and software guides listed above. |
On CCO at:
Technical Documents: Documentation Home Page: Cisco Product Documentation: Broadband/Cable Solutions: Cisco uBR900 Series Cable Access Routers
On the Documentation CD-ROM at:
Cisco Product Documentation: Broadband/Cable Solutions: Cisco uBR900 Series Cable Access Routers
Feature modules describe new features supported by Release 12.1, and are updates to the Cisco IOS documentation set. A feature module consists of a brief overview of the feature, benefits, configuration tasks, and a command reference. As updates, the feature modules are available online only. Feature module information is incorporated in the next printing of the Cisco IOS documentation set.
On CCO at:
Technical Documents: Documentation Home Page: Cisco IOS Software Configuration: Cisco IOS Release 12.1: New Feature Documentation
On the Documentation CD-ROM at:
Cisco Product Documentation: Cisco IOS Software Configuration: Cisco IOS Release 12.1: New Feature Documentation
The Cisco IOS software documentation set consists of the Cisco IOS configuration guides, Cisco IOS command references, and several other supporting documents that are available in electronic form on the Documentation CD-ROM and CCO, as well as separately orderable in printed versions.
Each module in the Cisco IOS documentation set consists of two books: a configuration guide and a corresponding command reference. Chapters in a configuration guide describe protocols, configuration tasks, Cisco IOS software functionality, and contain comprehensive configuration examples. Chapters in a command reference provide complete command syntax information. Use each configuration guide with its corresponding command reference.
On CCO and the Documentation CD-ROM, two master hot-linked documents provide information for the Cisco IOS software documentation set.
On CCO at:
Technical Documents: Documentation Home Page: Cisco IOS Software Configuration: Cisco IOS Release 12.1: Configuration Guides and Command References
On the Documentation CD-ROM at:
Cisco Product Documentation: Cisco IOS Software Configuration: Cisco IOS Release 12.1: Configuration Guides and Command References
Table 6 describes the contents of the Cisco IOS Release 12.1 software documentation set, which is available in electronic form and in printed form upon request.
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Note You can find the most current Cisco IOS documentation on CCO and the Documentation CD-ROM. These electronic documents may contain updates and modifications made after the hard-copy documents were printed. |
On CCO at:
Technical Documents: Documentation Home Page: Cisco IOS Software Configuration: Cisco IOS Release 12.1
On the Documentation CD-ROM at:
Cisco Product Documentation: Cisco IOS Software Configuration: Cisco IOS Release 12.1
| Books | Major Topics |
|---|---|
| Configuration Fundamentals Overview |
| Transparent Bridging |
| Preparing for Dial Access |
| Interface Configuration Overview |
| IP Overview |
| AppleTalk and Novell IPX Overview |
| Overview |
| Multiservice Applications Overview |
| Quality of Service Overview |
| Security Overview |
| Cisco IOS Switching Services Overview |
| Introduction: Wide-Area Networking Overview |
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Note Cisco Management Information Base (MIB) User Quick Reference is no longer published. If you have an account with CCO, you can find latest list of MIBs supported by Cisco. To reach the Cisco Network Management Toolkit, press Login at CCO and go to Software Center: Network Mgmt Products: Cisco Network Management Toolkit: Cisco MIB. |
You can access the most current Cisco documentation on the World Wide Web at http://www.cisco.com, http://www-china.cisco.com, or http://www-europe.cisco.com.
Cisco documentation and additional literature are available in a CD-ROM package, which ships with your product. The Documentation CD-ROM is updated monthly. Therefore, it is probably more current than printed documentation. The CD-ROM package is available as a single unit or as an annual subscription.
Registered CCO users can order the Documentation CD-ROM and other Cisco Product documentation through our online Subscription Services at http://www.cisco.com/cgi-bin/subcat/kaojump.cgi.
Nonregistered CCO users can order documentation through a local account representative by calling Cisco's corporate headquarters (California, USA) at 408 526-4000 or, in North America, call 800 553-NETS (6387).
Cisco provides Cisco Connection Online (CCO) as a starting point for all technical assistance. Warranty or maintenance contract customers can use the Technical Assistance Center. All customers can submit technical feedback on Cisco documentation using the web, e-mail, a self-addressed stamped response card included in many printed documents, or by sending mail to Cisco.
Cisco continues to revolutionize how business is done on the Internet. Cisco Connection Online is the foundation of a suite of interactive, networked services that provides immediate, open access to Cisco information and resources at anytime, from anywhere in the world. This highly integrated Internet application is a powerful, easy-to-use tool for doing business with Cisco.
CCO's broad range of features and services helps customers and partners to streamline business processes and improve productivity. Through CCO, you will find information about Cisco and our networking solutions, services, and programs. In addition, you can resolve technical issues with online support services, download and test software packages, and order Cisco learning materials and merchandise. Valuable online skill assessment, training, and certification programs are also available.
Customers and partners can self-register on CCO to obtain additional personalized information and services. Registered users may order products, check on the status of an order and view benefits specific to their relationships with Cisco.
You can access CCO in the following ways:
You can e-mail questions about using CCO to cco-team@cisco.com.
The Cisco Technical Assistance Center (TAC) is available to warranty or maintenance contract customers who need technical assistance with a Cisco product that is under warranty or covered by a maintenance contract.
To display the TAC web site that includes links to technical support information and software upgrades and for requesting TAC support, use www.cisco.com/techsupport.
To contact by e-mail, use one of the following:
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In North America, TAC can be reached at 800 553-2447 or 408 526-7209. For other telephone numbers and TAC e-mail addresses worldwide, consult the following web site: http://www.cisco.com/warp/public/687/Directory/DirTAC.shtml.
If you have a CCO login account, you can access the following URL, which contains links and tips on configuring your Cisco products:
This URL is subject to change without notice. If it changes, point your Web browser to CCO, press Login, and click on this path: Technical Assistance Center: Technical Tips.
The following sections are provided from the Technical Tips page:
If you are reading Cisco product documentation on the World Wide Web, you can submit technical comments electronically. Click Feedback in the toolbar and select Documentation. After you complete the form, click Submit to send it to Cisco.
You can e-mail your comments to bug-doc@cisco.com.
To submit your comments by mail, for your convenience many documents contain a response card behind the front cover. Otherwise, you can mail your comments to the following address:
Cisco Systems, Inc.
Document Resource Connection
170 West Tasman Drive
San Jose, CA 95134-9883
We appreciate and value your comments.

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Posted: Thu Aug 17 14:35:29 PDT 2000
Copyright 1989-2000©Cisco Systems Inc.