Cisco Octal-Port DMT ATU-C Line Card Technical manual

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Cisco IOS Release 12.1(6)DA
Octal-Port DMT ATU-C Line Card
This feature module describes the Cisco IOS support for the octal-port DMT ATU-C (8xDMT) line card.
It includes information on new and modified commands.
This document includes the following sections:
•Feature Overview, page 1
•Supported Platforms, page 4
•Supported Standards, MIBs, and RFCs, page 5
•Prerequisites, page 6
•Configuration Tasks, page 6
•Configuration Examples, page 9
•Command Reference, page 10
•Glossary, page 27
Feature Overview
The 8xDMT line card provides higher port density for the Cisco 6015, Cisco 6160, and Cisco 6260. This
line card:
•Supports eight ADSL modem connections per card.
•Converts ADSL modulation from the line card into digital data streams to and from the NI-2 card.
•Negotiates the line rate with the customer premises equipment (CPE) when it trains and bases the
rate on line quality and distance.
•Provides subscriber and port provisioning through DSL profiles.
– Allows single latency—Fast or interleaved path selection.
– Supports trellis encoding.
– Supports bit swapping.
•Interoperates with certain CPE. For more detailed information, see the “Supported Platforms”
section on page 4.
Note Check with a Cisco customer representative to verify CPE compatibility with
the 8xDMT.

Octal-Port DMT ATU-C Line Card
Feature Overview
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Cisco IOS Release 12.1(6)DA
Benefits
G.hs Support (ITU G.994.1)
G.hs support is provided through both the MIB and the CLI. Features from G.hs that are
supported include:
•Enabling/disabling all or one of the following modes.
– G.dmt
– T1.413 Issue 2
– G.lite
•Setting auto mode defers the mode selection to the ATU-R.
•Displaying current mode/capability.
Bit Swapping
Bit swapping is a mechanism that allows DMT transceivers to reallocate bits between carriers and adjust
gain scaling based on the carrier SNR margin.
Fast or Interleaved Path Selection
The fast path feature allows you to configure either the fast or the interleave path via DSL profile
configuration commands provided that the CPE also supports fast path. You can use either the interleave
or fast path with the 8xDMT line card provided that the CPE also supports fast path. The fast path
provides improved latency characteristics for applications that cannot tolerate latency (for
example, voice).
The parameters for either path are configurable using the DSL profile configuration commands. Note that
although you can configure both paths, only one path will actually be enabled (dual latency is not
supported at this time). Thus the maximum bit rates for the unused path must be zero. For example, to
configure and use the fast path, you must specify nonzero maximum bit rates for the fast path. Once you
configure the maximum bit rates for the fast path, the rates for the interleave path must be zero. The IOS
software ensures that only one path is enabled at a given time.
Trellis Encoding
Trellis encoding is a method of providing better performance in a noisy environment. The end result of
using Trellis encoding is that you can transmit at faster line rates with lower error rates, thus providing
a faster overall throughput in a moderately noisy environment. You can enable or disable trellis encoding
for a specific DSL profile.
Enhanced Line Quality Monitoring and Management
The 8xDMT improves the manageability of DMT ports on supported DSLAMs. The following
commands are used to configure this functionality:
•dmt minrate-blocking
DMT minrate-blocking customizes the DMT port reaction to lines that train below configured
minimum bit rates. Formerly, if a line trained below the configured minimum bit rate threshold, it
would generate a minor alarm, but the DMT port remained active. The dmt minrate-blocking
prevents DMT ports from training when bit rates fall below the configured minimum threshold
specified in the dmt bitrate minimum command.

Octal-Port DMT ATU-C Line Card Feature Overview
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Cisco IOS Release 12.1(6)DA
Note The original option, which generates a minor alarm when configured minimum bit rates are
not met, is configured by default in DSL profiles. The default configuration is no dmt
minrate-blocking.
•dmt rate-adaptation
The dmt rate-adaptation command monitors the signal-to-noise ratio (SNR) on DSL lines. When
enabled, software monitors the upstream and downstream DMT ports for low SNR margins. When
the actual upstream or downstream margin falls below the dmt rate-adaptation margin for the
duration of the configured rate-adaptation interval, the line drops and attempts to retrain. If the
line is able to retrain, it trains to a lower bit rate with improved SNR margins.
Restrictions
The 8xDMT card is not spectrally compatible with SDSL, G.shdsl, or IDSL. Place these cards in a
separate chassis half when using them in the same chassis as 8xDMT line cards.
Related Features and Technologies
The 8xDMT line card is an upgrade of the 4xDMT (6260) and 4xFlexi (6160, 6260, 6015) line cards.
Related Documents
Hardware Documents
A complete list of all DSL hardware product related documentation is available on the World Wide Web
at http://www.cisco.com/univercd/cc/td/doc/product/dsl_prod/index.htm.
Software Documents
A complete list of all DSL IOS software product related documentation is available on the World Wide
Web at http://www.cisco.com/univercd/cc/td/doc/product/dsl_prod/ios_dsl/index.htm.
In the ATM software product related documentation, look for information pertaining to the
Cisco LightStream 1010, which uses the same software base as the NI-2 DSL systems. This
documentation is available on the World Wide Web at
http://www.cisco.com/univercd/cc/td/doc/product/atm/index.htm.

Octal-Port DMT ATU-C Line Card
Supported Platforms
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Cisco IOS Release 12.1(6)DA
Supported Platforms
DSLAMs
This feature supports the 8xDMT line card on the Cisco 6015, Cisco 6160, and Cisco 6260 platforms
with NI-2. Table 1details the total available ADSL modem connections for each chassis.
The 8xDMT is designed for use with the Cisco 6015, Cisco 6160, or Cisco 6260 chassis in one of the
following configurations:
•Cisco 6015, Cisco 6160, or Cisco 6260 with a POTS splitter chassis—Provisions one modem
directly and is physically connected to one specific subscriber line through the POTS
splitter chassis.
•Cisco 6015, Cisco 6160, or Cisco 6260 without a POTS splitter chassis—Provisions one modem
directly and is physically connected to one specific subscriber line through the main distribution
frame (MDF) connections.
CPE
•Cisco 677
•Cisco 678
•Cisco Soho 77
•Cisco 827
•Cisco IAD 2423
•Cisco 1700, Cisco 2600, and Cisco 3600 series with ADSL WIC
•Alcatel Speed Touch Home
•Alcatel Speed Touch Pro
•Efficient Networks 5260 and 5262
•Westell modems based on Alcatel Microelectronics firmware version 1.4.1
•CPE using ADI chipsets with firmware versions 0X3019BE70 (Version 3.0),
0X2219BE04 (Version 2.2), or 0X2019BE2D (Version 2.0) should operate similar to the Cisco 677
Note A correct firmware version does not guarantee interoperation with third-party CPE. Some
hardware variations can affect performance and error rates. Test the interoperation of CPE
with the 8xDMT in the targeted deployment model before provisioning service.
Table 1 Number of Available Modem Connections for Each Chassis
Chassis Number of Available 8xDMT Slots Total ADSL Modem Connections
Cisco 6015 6 48
Cisco 6160 32 256
Cisco 6260 30 240

Octal-Port DMT ATU-C Line Card Supported Standards, MIBs, and RFCs
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Cisco IOS Release 12.1(6)DA
Supported Standards, MIBs, and RFCs
Standards
•ANSI T1.413-Issue 2, Category 1 only
•ANSI T1.413-Issue 2, Annex F (Reduced NEXT)
•Universal Test & Operations PHY for ATM, Level 2; A standard for transport of ATM cells over a
16-bit parallel data bus. See ATM Forum document af-phy-0039.000.
•ITU G.992.1, Annex A (G.dmt)
•ITU G.992.2. (G.lite)
•ITU G.994.1. (G.hs)
Standard MIBS
To obtain lists of supported MIBs by platform and Cisco IOS release and to download MIB modules, go
to the Cisco MIB web site on Cisco Connection Online (CCO) at
http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.
•IETF RFC 1695, Definitions of Managed Objects for ATM Management Version 8.0 using SMIv2
•IETF RFC 2662, Definitions of Managed Objects for the ADSL Line (obsoletes ADSL Forum TR-
006, SNMP-based ADSL Line MIB)
– Objects not supported for 8xDMT:
From AdslLineConfProfileEntry - adslAtucConfRateChanRatio, adslAtucConfMaxSnrMgn,
adslAtucConfUpshiftSnrMgn, adslAturConfRateChanRatio, adslAturConfMaxSnrMgn,
adslAturConfUpshiftSnrMgn,adslAturConfMinUpshiftTime.
AdslLineAlarmConfProfileEntry
•ADSL Forum TR-014, DMT Line Code Specific MIB
– Objects not supported for 8xDMT:
FromAdslLineDmtConfProfileEntry- adslAtucDmtConfFreqBins, adslAturDmtConfFreqBins,
adslAtucDmtConfInterleavePath,adslAtucDmtConfFastPath,adslAturDmtConfInterleavePath,
adslAturDmtConfFastPath.
Cisco-Derived MIBS
•CISCO-ADSL-LINE-MIB
– Objects not supported for DMT8:
•CISCO-ADSL-DMT-LINE-MIB
– Objects not supported for DMT8:
From the cAdslDmtLineConfProfileGroup cAdslAtucDmtConfBitSwapEnabled,
cAdslAtucDmtConfBitSwapFrom, cAdslAtucDmtConfBitSwapTo. You can set these objects
via SNMP, however, the 8xDMT cards will ignore these objects when provisioning ports
for service.
To obtain lists of supported MIBs by platform and Cisco IOS release and to download MIB modules, go
to the Cisco MIB web site on Cisco Connection Online (CCO) at
http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.

Octal-Port DMT ATU-C Line Card
Prerequisites
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Cisco IOS Release 12.1(6)DA
Prerequisites
To use the 8xDMT feature, you must have one of the following DSLAMs with the 8xDMT line card, and
IOS 12.1(6) or above installed:
•Cisco 6015
•Cisco 6160
•Cisco 6260
Configuration Tasks
See the following sections for configuration tasks for the 8xDMT feature. Each task in the list indicates
if the task is optional or required.
•Preprovisioning the 8xDMT Line Card, page 6 (optional)
•Creating and Associating a DSL Profile with Each Port, page 7 (required)
•Modifying the DSL Profile, page 7 (optional)
Preprovisioning the 8xDMT Line Card
Starting at the global configuration prompt, use the following commands to preprovision a slot for use
with the 8xDMT line card:
Tips After you have completed these steps, insert the 8xDMT line card to activate the card with your
preprovisioned configuration.
Verifying the Preprovisioned Slot
Use the show running-configuration command to verify that you preprovisioned the slot correctly.
Command Purpose
Step 1 DSLAM(config)# slot 1 ATUC-1-DMT8 This command associates the 8xDMT line card with
the specified slot.
Step 2 DSLAM(config)# dsl-profile 8xDMT Creates and names the DSL profile, 8xDMT in
this example.
Step 3 DSLAM(config-dsl-prof)# exit Return to the global configuration prompt.
Step 4 DSLAM(config)# interface atm1/1 Enter interface configuration mode on the port
where you will associate the 8xDMT DSL profile.
Repeat this process on each port that you wish to
associate with a DSL profile.
Step 5 DSLAM(config-if)# dsl profile 8xDMT Associates the DSL profile named 8xDMT with
atm interface 1/1.
Step 6 DSLAM(config-if)# exit Return to the global configuration prompt.

Octal-Port DMT ATU-C Line Card Configuration Tasks
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Cisco IOS Release 12.1(6)DA
Creating and Associating a DSL Profile with Each Port
Before starting this configuration task, install the 8xDMT line card. Refer to the Octal-Port DMT ATU-C
Line Card FRU Installation and Configuration Notes for information on installing the 8xDMT line card.
Starting at the global configuration prompt, use the following procedure to associate a DSL profile with
a port:
Verifying the DSL Profiles
You can use the show dsl profile profile-name command to verify that a DSL profile is attached to a port.
You can also use the show running-configuration command to verify that the DSL profile is associated
with a port.
Tips If no DSL profile appears in the show running-configuration command output, the default
DSL profile is enabled. See the “Command Reference” section on page 10 for the default
configuration values.
Modifying the DSL Profile
Starting at the global configuration prompt, use the following procedure to modify the default bit rate,
signal-to-noise ratio, DMT check bytes, and overhead framing parameters in your DSL profile:
Caution Before migrating from interleave mode to fast path, determine whether the deployed CPEs offer
support for the feature. The Cisco 600 series CPEs currently do not support fast path.
Command Purpose
Step 1 DSLAM(config)# dsl-profile 8xDMT Select the profile that you want to attach to the
selected port. The profile name 8xDMT is used as
an example.
Step 2 DSLAM(config-dsl-prof)# exit Return to the global configuration prompt.
Step 3 DSLAM(config)# interface atm1/1 Enter interface configuration mode on the port
where you will associate the 8xDMT DSL profile.
Repeat this process on each port that you wish to
associate with a DSL profile.
Step 4 DSLAM(config-if)# dsl-profile 8xDMT Associate the DSL profile 8xDMT with
atm interface 1/1.
Step 5 DSLAM(config-if)# exit Return to the global configuration prompt.
Command Purpose
Step 1 DSLAM(config)# dsl-profile 8xDMT Enter DSL profile configuration mode.
Step 2 DSLAM(config-dsl-profile)# dmt bitrate
maximum fast downstream 3200 upstream 640 Set a DMT bit rate of 3200 kbps downstream and 640 kbps
upstream on the fast path. Automatically configures the
interleaved path to 0 kbps.

Octal-Port DMT ATU-C Line Card
Monitoring and Maintaining the 8xDMT Line Card
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Troubleshooting Tips
Cisco provides Cisco.com as a starting point for all technical assistance. Customers and partners can
obtain documentation, troubleshooting tips, and sample configurations from online tools.
For Cisco.com registered users, additional troubleshooting tools are available from the TAC website. To
obtain troubleshooting help, go to the Cisco Troubleshooting Assistant web site on Cisco Connection
Online (CCO) at:
http://www.cisco.com/kobayashi/support/tac/tsa/dslstep.html
Also see the “Monitoring and Maintaining the 8xDMT Line Card” section on page 8.
Monitoring and Maintaining the 8xDMT Line Card
Use the following commands to monitor and maintain the 8xDMT line card:
Step 3 DSLAM(config-dsl-profile)# dmt
check-bytes fast downstream 0 upstream 0 Set the upstream and downstream FEC check (redundancy) bytes
to 0.
Step 4 DSLAM(config-dsl-profile)# dmt margin
downstream 12 upstream 6 Set the downstream and upstream signal-to-noise ratio (SNR)
margins for a DSL profile.
Step 5 DSLAM(config-dsl-profile)# dmt
overhead-framing mode1 Set the overhead framing mode, in this example to 1.
Step 6 DSLAM(config-dsl-profile)# exit Return to the global configuration prompt.
Command Purpose
Command Purpose
DSLAM# show dsl interface atm s lot/port
DSLAM# show dsl status DMT
These commands display basic information about the DSL link,
including port status, dsl statistics, line errors, and cards detected.
DSLAM# show facility-alarm status The show facility-alarm status command displays all of the current
major and minor alarms and the user-configurable alarm thresholds
for temperature. After an alarm condition is indicated (by LEDs or
bells), you can use the show facility-alarm status command to
determine the cause of the alarm.
Note You must turn on the alarms in the profile for alarms to
be displayed.
DSLAM# show hardware The show hardware command shows information on each of the
slots in your chassis. It tells whether line cards, fan trays, and PEMs
are present.

Octal-Port DMT ATU-C Line Card Configuration Examples
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Cisco IOS Release 12.1(6)DA
Configuration Examples
The following example shows a profile named 8xDMT2 being created. The profile uses the default
profile values for any parameters not specified.
Current configuration : 7019 bytes
!
version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname DSLAM
!
boot system flash:ni2-dsl-mz.121-6.DA.bin
slot 1 ATUC-4FLEXIDMT
slot 2 ATUC-1-DMT8
slot 3 ATUC-4FLEXIDMT
slot 4 ATUC-4FLEXIDMT
slot 5 ATUC-4FLEXIDMT
slot 6 ATUC-4FLEXIDMT
enable password cisco
!
!
!
!
!
!
dsl-profile default
dmt bitrate maximum interleaved downstream 8032 upstream 864
cap bitrate maximum downstream 7168 upstream 1088
!
dsl-profile 8xdmt
!
dsl-profile 8xDMT2
dmt overhead-framing mode1
dmt check-bytes fast downstream 12 upstream 6
dmt margin downstream 12 upstream 6
dmt bitrate maximum fast downstream 3200 upstream 640
dmt bitrate maximum interleaved downstream 0 upstream 0
network-clock-select 1 system
ip subnet-zero
ip host-routing
no ip finger

Octal-Port DMT ATU-C Line Card
Command Reference
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Cisco IOS Release 12.1(6)DA
Command Reference
This section documents the new and modified commands that are specific to the8xDMT feature. All
other commands used with this feature are documented in the Command Reference for Cisco DSLAMS
with NI-2. For information on other Cisco IOS commands that can be used on the NI-2 DSL systems,
see the Cisco ATM Switch Router Command Reference Guide.