MODEL 7510 DSU
USER’S GUIDE
Document No. 7510-A2-GB20-10
November 1997
Contents
About This Guide
H
H
H
Document Purpose and Intended Audience . . . . . . . . . . . . . . . . . . . . . . . . . v
Document Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
Product-Related Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
1
2
About the DSU
H
H
H
Model 7510 DSU Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Typical DSU Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
User Interface Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Rear Panel Interface Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Using the Asynchronous Terminal Interface
H
H
H
Connecting to the Terminal Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Initiating an ATI Session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Screen Format Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
What Affects Screen Displays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Screen Work Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Navigating the Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Keyboard Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Screen Function Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Switching to the Screen Function Key Area . . . . . . . . . . . . . . . . . . . . . 2-7
Ending an ATI Session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
H
H
3
Customizing the DSU
H
Identifying the Device and System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Saving Configuration Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Configuring the DSU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Configuration Option Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Accessing and Displaying Configuration Options . . . . . . . . . . . . . . . . 3-3
H
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Contents
4
5
6
Monitoring the DSU
H
H
What to Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Viewing System and Test Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Health and Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Self-Test Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Test Status Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
Viewing Network Interface Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Viewing Network Performance Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Monitoring the LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8
System LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9
Network LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10
Port LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11
H
H
H
Testing
H
H
Accessing the Test Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Running Network Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
CSU or External Network Loopback . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
DSU or Internal Network Loopback . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
Send V.54 Up/Down Sequences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
511 Test Pattern for the Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
Running Data Port Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Local Loopback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
511 Test Pattern for the DTE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Running the Lamp Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
Ending an Active Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
H
H
H
Messages and Troubleshooting
H
H
H
H
H
Messages and Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Responding to Device Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
Resetting the DSU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Displaying DSU Identity Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
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Contents
A Configuration Option Tables
H
H
H
H
H
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
System Options Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
Network Interface Options Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-4
Data Port Options Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-5
Terminal Port Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-7
B Worksheets
H
H
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
Configuration Worksheets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
C Cables and Pin Assignments
H
H
H
H
H
H
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
Terminal Port EIA-232 Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-2
V.35 User Data Port Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-3
Standard EIA-232-D Crossover Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-4
LAN Adapter Converter and Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-5
Modular RJ48S DDS Network Interface Cable . . . . . . . . . . . . . . . . . . . . . . C-5
D Technical Specifications
Glossary
Index
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About This Guide
Document Purpose and Intended Audience
This guide contains information needed to set up, configure, and operate the
Model 7510 DSU and is intended for installers and operators.
Document Summary
Section
Description
Chapter 1
About the DSU. Describes the DSU features and shows
examples of typical configurations.
Chapter 2
Using the Asynchronous Terminal Interface. Provides
instructions for accessing the user interface and navigating
the screens.
Chapter 3
Chapter 4
Chapter 5
Chapter 6
Appendix A
Appendix B
Appendix C
Appendix D
Customizing the DSU. Provides procedures for setting up
the user interface and DSU configuration.
Monitoring the DSU. Describes monitoring details about the
LEDs, DSU status, and network statistics.
Testing. Provides details about available tests and test
setup.
Messages and Troubleshooting. Provides information on
device messages and troubleshooting.
Configuration Option Tables. Contains all configuration
options, default settings, and possible settings.
Worksheets. Contains all the configuration options, default
settings, and possible settings to use for planning.
Cables and Pin Assignments. Contains connector and
interface details.
Technical Specifications. Contains physical and regulatory
specifications of the DSU.
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About This Guide
Section
Glossary
Index
Description
Defines acronyms and terms used in this document.
Lists key terms, acronyms, concepts, and sections in
alphabetical order.
Product-Related Documents
Document Number
Document Title
7510-A2-GN10
Model 7510 DSU Startup Instructions
To order additional product documentation, refer to Warranty, Sales, and Service
Information on page A at the beginning of this User’s Guide.
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vi
About the DSU
1
Model 7510 DSU Features
The DSU provides an interface between the customer premises equipment (CPE)
and a Digital Data Service (DDS) network.
The DSU’s features and capabilities include:
H
H
Easy Installation. Connects to your equipment using standard connectors
and cables.
Easy Configuration. A compact and well-thought set of configuration options
minimizes your customization effort.
H
H
DDS Operation. Operates at 56 and 64 kbps CC (clear channel).
Local Area Data Set (LADS) Operation. Operates at 56 and 64 kbps
full-duplex as a limited-distance modem.
H
H
H
Autorating. Automatically adjusts to the detected line rate.
Data Port Rates. Automatically adjusts to the DDS or LADS operating rates.
Asynchronous Terminal Interface (ATI). Provides a menu-driven
VT100-compatible interface for configuring and managing the DSU.
— Local Management. Provides local management using an asynchronous
terminal connection through the Terminal port.
— Remote Management. Provides remote management using an external
modem through the Terminal port.
H
H
Diagnostics. Lets you diagnose device and network problems with digital
loopbacks and pattern tests.
Device and Test Monitoring. Lets you track and evaluate the unit’s
operation with status and test result information.
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1-1
About the DSU
Typical DSU Configurations
The following illustration shows a typical LAN/WAN interconnection application for
the DSU. The routers connected to the DSU at each location provide the LAN
interconnection.
DDS
Network
Router
Router
DSU
DSU
97-15084-02
The DSU can also be used in a Frame Relay network.
Frame
Relay
Network
Router
Router
DSU
DSU
97-15271-01
Two DSUs can be connected back-to-back to act as Local Area Data Sets
(LADS).
56 kbps
Router
Router
DSU
DSU
97-15236-01
Table D-2 in Appendix D shows the maximum distances for LADS applications.
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About the DSU
User Interfaces
There are two types of user interfaces for the DSU:
H
H
Menu-driven Asynchronous Terminal Interface (ATI) screens (see Chapter 2,
Using the Asynchronous Terminal Interface).
Front panel LED status indicators (see Chapter 4, Monitoring the DSU).
7510 DSU
TS (105)
CTS (106D)TR (108)
OK
ALARM TEST DM
OOS
OOF
NS
TXD (103R)XD (10R4)
Port
System
Network
56/64K
497-15245
Rear Panel Interfaces
The following illustration shows the physical interfaces of the DSU. Information
about the installation of the DSU is contained in the Model 7510 DSU Startup
Instructions.
Modem
DTE
or
Terminal
NETWORK
TERMINAL
POWER
D
T
E
Power
Network
497-15237
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1-3
Using the Asynchronous
Terminal Interface
2
Connecting to the Terminal Port
The device used for the Asynchronous Terminal Interface (ATI) can be a
VT100-compatible async terminal, or a PC running emulation software. The
terminal or PC can be connected to the Terminal port directly, or through an
external modem.
Ensure that the device you connect communicates using these settings:
H
H
H
H
Data rate set to 9.6 kbps.
Character length set to 8.
Parity set to None.
Stop Bits set to 1.
Terminal port settings cannot be changed from the ATI.
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2-1
Using the Asynchronous Terminal Interface
Initiating an ATI Session
The user interface is blank until activated. Press Return to activate the user
interface. The first time you do this the Main Menu screen is displayed.
main
Device Name:
Model: 7510
MAIN MENU
Status
Test
Configuration
Control
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
Ctrl-a to access these functions Exit
Entry to all of the DSU’s tasks begins at the Main Menu screen, which has four
menus or branches.
Select . . .
To . . .
Status
View results of diagnostic tests, network status of interfaces, statistics,
LEDs, and DSU identity information.
Test
Select and cancel tests for the DSU’s interfaces.
Configuration Display and edit the configuration options.
Control
Establish identification for the DSU and system, or to initiate a power-up
reset of the DSU.
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Using the Asynchronous Terminal Interface
MAIN MENU
Status
Test
Configuration
Control
Load
Configuration
From...
Test
Configuration
Control
Status
Edit/Display
• System
• Network Tests
• Data Port Tests
• Lamp Test
• System and Test Status
• Network Interface Status
• Device Name
• Reset Device
• Network
• Network Performance
Statistics
• Data Port
• Terminal Port
• Abort All Tests
• Display LEDs
• Identity
497-15238
Screen Format Types
Three types of screen formats are available on the ATI.
Use the screen format . . . To . . .
Menu selection
Input
Display a list of available functions for user selection.
Add or change information on a screen.
Input or edit fields that have an Underline in the field value
or selection. See Screen Work Areas.
Display
Display configuration information and results from
performance and DSU-specific tests.
Display-only fields that have no underline in the field value.
What Affects Screen Displays
What appears on the screens depends on the:
H
H
Current configuration – How the DSU is currently configured.
Data selection criteria – What you entered in previous screens.
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Using the Asynchronous Terminal Interface
Screen Work Areas
There are two user work areas:
H
Screen area – This is the area above the dotted line that provides the menu
path, menus, and input fields.
The menu path appears as the first line on the screen. In this manual, the
menu path is presented as a menu selection sequence with the names of the
screens:
Main Menu → Configuration (Load Configuration From) →
Configuration Edit/Display → Data Port Options
H
Screen function key area – This is the area below the dotted line that lists
function keys specific to the screen, field value choices, and system
messages.
Menu Path
main/configuration/edit/port
Device Name: Node A
Model: 7510
DATA PORT OPTIONS
Invert Transmit Clock:
Disable
Port (DTE) Initiated Loopbacks: Disable
Bilateral Loopback:
Carrier Control by RTS:
CTS Control:
RLSD Control:
DSR Control:
Disable
Constant
Standard
Standard
Standard
Enable
Input Fields
Monitor DTR:
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
Ctrl-a to access these functions, ESC for previous menu
Save
Select: Disable, Enable
MainMenu
Exit
Screen
Function
Keys
No Signal
System
Messages
Field Value
Choices
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Using the Asynchronous Terminal Interface
Navigating the Screens
You can navigate the screens by:
H
H
H
Using keyboard keys
Using screen function keys
Switching between the two screen work areas
Keyboard Keys
Use the following keyboard keys to navigate within the screen.
To . . .
Press . . .
Move cursor between the screen area and the screen function
keys area below the dotted line at the bottom of the screen
Ctrl-a
Return to the previous screen
Esc
Tab
Move cursor to the next field on the screen
Accept entry or display valid options on the last row of the screen Return (Enter)
when pressed before entering data or after entering invalid data
Move cursor to the previous field
Ctrl-k
Select the next valid value for the field
Spacebar
Delete character that the cursor is on
Delete (Del)
Up Arrow or Ctrl-u
Move cursor up one field within a column on the same screen
Move cursor down one field within a column on the same screen Down Arrow or Ctrl-d
Move cursor one character to the right in a text field
Move cursor one character to the left in a text field
Right Arrow or Ctrl-f
Left Arrow or Ctrl-b
Ctrl-l
Redraw the screen display, clearing information typed in but not
yet entered
" Procedure
To make a menu or field selection:
1. Press the tab key or the right arrow key to position the cursor on a menu or
field selection. Each selection is highlighted as you press the key to move the
cursor from position to position.
2. Press Return. The selected menu or screen appears.
3. Continue Steps 1 and 2 until you reach the screen you want.
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Using the Asynchronous Terminal Interface
The current setting or value appears to the right of the field name. The valid
choices for the field are displayed in the screen function area. You can enter
information into a selected field by typing in the first letter or letters of a field value
or command.
If a field is blank and the Field Values screen area displays valid selections, press
the spacebar and the first valid value for the field will appear. Continue pressing
the spacebar to scroll through other valid values.
Screen Function Keys
All screen function keys located below the dotted line operate the same way
(upper- or lowercase) throughout the screens.
For the screen
function . . .
Select . . . And press Return to . . .
Clear
C or c
C or c
Clear status messages for one-time events.
ClrStats
Clear network performance statistics and refresh the
screen.
Exit
E or e
M or m
D or d
U or u
R or r
R or r
S or s
Terminate the async terminal session.
Return to the Main Menu screen.
Display the next page.
MainMenu
PgDn
PgUp
Display the previous page.
Refresh
ResetMon
Save
Update screen with current information.
Reset an active Monitor 511 test counter to zero.
Save information.
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Using the Asynchronous Terminal Interface
Switching to the Screen Function Key Area
Selecting Ctrl-a allows you to switch between the two screen work areas to
perform all screen functions.
" Procedure
To access the screen function area below the dotted line:
1. Press Ctrl-a to switch from the screen area to the screen function key area
below the dotted line. The available selections for the first input field appear
on the last line as shown below.
2. Select either the function’s designated (underlined) character or press the tab
key until you reach the desired function key.
Example:
To reset the Monitor 511 error counter to zero, type r or R (ResetMon).
3. Press Return. The function is performed.
4. To return to the screen area above the dotted line, press Ctrl-a again.
main/test/network
Device Name:
Model: 7510
NETWORK TESTS
Status
Test
Command
Result
0:00:00
CSU Loopback:
DSU Loopback:
Start
Start
Inactive
Inactive
0:00:00
Send V.54 Up:
Send
Sending
Send V.54 Down: Send
Inactive
Send 511:
Monitor 511:
Start
Stop
Inactive
Active
0:00:00
125:08:48
Errors 99999+
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
Ctrl-a to access these functions, ESC for previous menu
MainMenu
Exit
ResetMon
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Using the Asynchronous Terminal Interface
Ending an ATI Session
Use the Exit function key from any screen to terminate the session.
" Procedure
To end an ATI session:
1. Press Ctrl-a to go to the screen function key area below the dotted line.
2. Save changes if required. A confirmation message appears if you have made
but not saved changes to your configuration.
3. Tab to Exit (or type e or E) and press Return. The User Interface Idle screen
appears.
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Customizing the DSU
3
Identifying the Device and System
Use the Device Name screen to determine the name that will be displayed at the
top of all ATI screens, and system information that will be displayed on the
Identity screen. To access the Device Name screen, follow this menu selection
sequence:
Main Menu → Control → Device Name
main/control/device name
Device Name:Node A
Model: 7510
DEVICE NAME
Device Name:
System Name:
System Location:
System Contact:
Node A
Clear
Clear
Clear
Clear
________________________________________
________________________________________
________________________________________
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
Ctrl-a to access these functions, ESC for previous menu
Save
MainMenu
Exit
Fields on the Device Name screen are null until you enter values. Allowable
values are any printable ASCII character. ASCII printable characters include:
H
H
H
H
Numeric 0–9
Upper or lower case A–Z
Space
All ASCII symbols
Use the left and right arrow keys to scroll through the fields. Select Clear to reset
a field to a null value.
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Customizing the DSU
" Procedure
To enter Device Name screen information:
1. Position the cursor in the Device Name field. Enter a name unique in your
system to identify the unit.
The maximum length of Device Name is 20 characters.
2. Position the cursor in the System Name field. Enter a name unique in your
network to identify the system.
The maximum length of System Name is 127 characters.
3. Position the cursor in the System Location field. Enter the physical location of
the system.
The maximum length of System Location is 127 characters.
4. Position the cursor in the System Contact field. Enter the name and contact
information for the person responsible for the unit.
The maximum length of System Contact is 127 characters.
5. Save the Device Name screen information as shown in the next section.
Saving Configuration Options
When changes are made to the configuration options, the changes must be
saved to take effect. Use the Save key or Save Configuration screen.
" Procedure
To save configuration options changes:
1. Press Ctrl-a to switch to the screen function key area below the dotted line.
2. Select Save and press Return.
NOTE:
When Exit is selected before Save, a Save Configuration screen appears
requiring a Yes or No response.
If you select . . .
Then . . .
Yes
No
The configuration is saved.
The Main Menu appears and changes are not saved.
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Customizing the DSU
Configuring the DSU
Configuration option settings determine how the DSU operates. Use the DSU’s
Configuration branch to display or change configuration option settings.
Configuration Option Areas
The DSU is shipped with factory settings in the Default Factory configuration
area. You can find default information by:
H
H
Referring to, Appendix A, Configuration Option Tables, or Appendix B,
Worksheets.
Accessing the Configuration branch of the DSU menu.
The DSU has two sets of configuration option settings. The Current Configuration
matches the Default Factory Configuration until modified and saved by the user.
Configuration Option Area Configuration Option Set
Current Configuration
The DSU’s active set of configuration options.
Default Factory Configuration A read-only configuration area containing the factory
default configuration options.
If the factory default settings do not support your network’s configuration,
customize the configuration options for your application.
Accessing and Displaying Configuration Options
To display the configuration options, you must first copy one configuration option
set into the edit area.
" Procedure
To load a configuration option set into the configuration edit area:
1. Follow this menu selection sequence:
Main Menu → Configuration (Load Configuration From)
2. Select Current Configuration or Default Factory Configuration. Press Return.
The selected configuration option set is loaded and the Configuration
Edit/Display menu screen appears.
See Appendix A for a list and explanation of the configuration options available.
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3-3
Monitoring the DSU
4
What to Monitor
This chapter presents information on how to access and monitor DSU status and
performance statistics on the DDS network. You can monitor DSU operations by
viewing:
H
H
H
H
H
System and Test Status screen
Highest priority Health and Status message on the last line of all screens
Network Interface Status screen
Network Performance Statistics screen
LEDs on the ATI Status screen or the DSU’s front panel
Table 4-1 shows the available indicators of alarm conditions on the network
interface and the User Data port.
Table 4-1. Alarm Indicator Locations
Status
Screen LED
Specific
Alarm Condition
Crossed Pairs
Y
Y
Y
Y
Y
Y
N
Y
Y
Y
N
N
No Signal (NS)
Out of Service (OOS)
Out of Frame (OOF)
Excessive Bipolar Violations (BPV)
Inband Framing Error
7510-A2-GB20-10
November 1997
4-1
Monitoring the DSU
Viewing System and Test Status
To view System and Test Status information, follow this menu selection
sequence:
Main Menu → Status → System and Test Status
The System and Test Status screen has three sections:
H
H
H
Health and Status – Displays messages in priority order (highest to lowest).
Refer to Table 4-2, Health and Status Messages.
Self-Test Results – Results of the Diagnostic test run on the device itself.
Refer to Table 4-3, Self-Test Results Messages.
Test Status – Currently active tests. Refer to Table 4-4, Test Status
Messages.
main/status/system
Device Name:Node A
Model: 7510
SYSTEM AND TEST STATUS
SELF-TEST RESULTS
HEALTH AND STATUS
TEST STATUS
Cross Pair Detection
No Signal hhh:mm:ss
Out of Service hhh:mm:ss
Out of Frame hhh:mm:ss
Excessive BPVs hhh:mm:ss
User Data Port DTR Off
Device Fail yyyyyyyy
DSU Operational
Device Fail
Memory Fail
Passed
No Test Active
CSU Loopback Active
Network-init. CSU LB Active
DSU Loopback Active
Network-init. DSU LB Active
V.54-initiated DSU LB Active
Local Loopback Active
Sending 511 on Port
Monitoring 511 on Port
Sending 511 on Network
Monitoring 511 on Network
Lamp Test Active
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
ESC for previous menu MainMenu Exit
Refresh
Clear
November 1997
7510-A2-GB20-10
4-2
Monitoring the DSU
Health and Status
The following messages appear in the first column of the System and Test Status
screen. The highest priority Health and Status message also appears on all ATI
screens on the bottom right.
Table 4-2. Health and Status Messages (1 of 2)
Message
What Message Indicates
What To Do
Cross Pair
Detection
The DDS Receive (RX) and
Transmit (TX) pairs are
crossed on the network
interface. Alarm LED is on.
Reverse the RX and TX pair at the
punchdown block or other
termination point.
No Signal
hhh:mm:ss
No signal is being received.
Local DSU network problem.
The Alarm and NS LEDs are
on and Network Performance
Statistics are active.
1. Verify that the network cable is
securely attached at both ends.
1
2. Contact network provider.
Out of Service
hhh:mm:ss
DSU is receiving out of
service code from the
network for the remote unit.
The Alarm and OOS LEDs
are on and Network
Performance Statistics are
active.
1. Verify that the remote site is in
service.
1
2. Contact network provider.
Out of Frame
hhh:mm:ss
DSU is detecting an out of
frame condition, associated
with:
1. Verify that the line rate matches
the configured rate.
1
2. Contact network provider.
H Receiving out of frame
code from the network.
H DSU detecting out of frame
errors with 64 kbps CC
data rate.
H DSU unable to synchronize
local receiver circuit with
line signal.
Excessive BPVs
hhh:mm:ss
Data rates do not match or
network trouble is causing
bipolar violations. Alarm LED
is on and Network
1. Verify that the network cable is
securely attached at both ends.
1
2. Contact network provider if
problem persists.
Performance Statistics are
active.
User Data Port
DTR Off
The DTE is not ready to
transmit or receive data. This that the DTE is powered up and
message will not appear
unless Monitor DTR is
enabled.
Check on the DTE status. Verify
asserting DTR.
1
hhh:mm:ss indicates the amount of time the condition has existed in hours, minutes,
and seconds. When the maximum time has been exceeded, 255:59:59+ appears.
7510-A2-GB20-10
November 1997
4-3
Monitoring the DSU
Table 4-2. Health and Status Messages (2 of 2)
Message
What Message Indicates
What To Do
Device Fail
yyyyyyyy
An internal error has been
detected by the operating
software. yyyyyyyy indicates
the 8-digit hexadecimal failure
code.
1. Provide the 8-digit failure code
shown (yyyyyyyy) to your service
representative.
2. Reset the DSU to clear the
condition and message.
DSU Operational DSU is functioning properly
and there are no status
No action needed.
messages to display.
Self-Test Results
The results of the last power-up or reset self-test appear in the middle column of
the System and Test Status screen.
Table 4-3. Self-Test Results Messages
Message
What Message Indicates
What To Do
1. Reset the DSU and try again.
Device Fail
One or more of the DSU’s integrated
circuit chips has failed device-level
testing.
2. Call your service
representative for assistance if
the message reappears.
Memory Fail DSU failed memory verification.
Passed
The DSU has been plugged in or
reset and has passed the diagnostic
test. There are no other status
messages.
No action needed.
November 1997
7510-A2-GB20-10
4-4
Monitoring the DSU
Test Status Messages
The Test Status Messages in the following table appear in the right column of the
System and Test Status screen.
Table 4-4. Test Status Messages
Test Status Message Meaning
No Test Active
Status message, indicating no local, remote, or network test in
progress.
CSU Loopback Active A CSU Loopback toward the network is currently active.
Network-init. CSU LB
Active
A CSU Loopback initiated by the network is currently active.
DSU Loopback Active A DSU Loopback toward the network is currently active.
Network-init. DSU LB
Active
A DSU Loopback initiated by the network is currently active.
H If the network service is 56 kbps, the network loopback is
non-latching. A non-latching loopback ends when the
network activation codes stop.
H If the network service is 64 kbps CC, the network loopback
is latching. This condition can only occur when the Network
Interface option Network-initiated DSU Loopback (64K CC)
is enabled. Refer to Table A-2, Network Interface Options.
V.54-initiated DSU LB A DSU loopback is active that was initiated by the detection of
Active
a V.54 sequence originated by the remote unit. This condition
can only occur when V.54 Initiated DSU Loopback is enabled.
Refer to Table A-2, Network Interface Options, Table A-2.
Local Loopback Active A local loopback toward the DTE is currently active.
Sending 511 on Port A 511 test pattern is being sent over the DTE port.
Monitoring 511 on Port DSU is monitoring a 511 test pattern over the DTE port.
Sending 511 on
Network
A 511 test pattern is being sent over the network interface.
Monitoring 511 on
Network
DSU is monitoring a 511 test pattern on the network interface.
Lamp Test Active
The Lamp Test is active, causing the LEDs on the front panel to
light.
7510-A2-GB20-10
November 1997
4-5
Monitoring the DSU
Viewing Network Interface Status
The network interface status fields are read-only:
H
Line Rate (Kbps). If the DSU is connected to an operating line and the Line
Rate (Kbps) shows Autobaud and does not change to a line rate within about
25 seconds, Line Rate (Kbps) may have to be reconfigured manually. Refer
to Table A-1, System Options.
H
Loop Loss (dB). The loop loss is the loss of signal strength of the receive
line signal from the local loop.
To view the Network Interface Status, follow this menu selection sequence:
Main Menu → Status → Network Interface Status
Table 4-5 describes the contents of the Network Interface Status screen.
Table 4-5. Network Interface Status Screen Contents
Field
Status
What the Status Indicates
Line Rate (Kbps)
56 Kbps
64 CC
64 LADS
Autobaud
Line rate on the network interface.
Autobaud indicates the DSU is
trying to determine the network line
rate. If this does not change to a
numeric value within about
25 seconds, you may need to set
the Line Rate manually.
No Signal
No signal can be detected over the
network interface.
Loop Loss (dB)
0 to –65 dB
Amount of loop loss – loss of signal
strength of the receive line signal
from the local loop, measured in
decibels.
Inoperative
The line may be disconnected.
November 1997
7510-A2-GB20-10
4-6
Monitoring the DSU
Viewing Network Performance Statistics
Performance statistics for the network interface are available to:
H
H
Monitor the current status of the network operations.
View the DSU’s performance statistics, which:
— Assist you in determining the duration of specific conditions.
— Provide a historical context for problem detection and analysis.
To view the Network Performance Statistics, follow this menu selection sequence:
Main Menu → Status → Network Performance Statistics
main/status/performance
Device Name:
Model: 7510
NETWORK PERFORMANCE STATISTICS
No Signal Count: 101920
26:33:08
0:00:00
8:53:49
Out of Service Count:
Out of Frame Count:
Excessive BPV Count:
Invalid BPV Count:
0
621
99830
87409
144:28:11
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
ESC for previous menu MainMenu Exit
Refresh
ClrStats
All counts show the number of occurrences since the last reset of the counters.
H
H
No Signal Count is the number of occurrences of a No Signal condition.
Out of Service Count is the number of occurrences of an Out of Service
(OOS) condition.
H
H
H
Out of Frame Count is the number of occurrences of an Out of Frame
(OOF) condition.
Excessive BPV Count is the number of times at least one invalid bipolar
violation was detected every 20 ms for a 2-second period.
Invalid BPV Count is a raw count of the number of invalid bipolar violations.
In the last column, hhh:mm:ss indicates the amount of time the condition has
existed in hours, minutes, and seconds. When the maximum time has been
exceeded, 255:59:59+ appears.
The screen appears with the cursor in the function area below the dotted line. To
update the performance statistics, select Refresh and press Return.
Select ClrStats and press Return to clear all statistics and refresh the screen.
7510-A2-GB20-10
November 1997
4-7
Monitoring the DSU
Monitoring the LEDs
The status of DSU LEDs can be viewed on the Display LEDs screen.
The 12 LEDs are organized into three groups:
H
H
H
System LEDs display the status of the unit
Network LEDs display the status of the network interface
Port LEDs display the activity on the user data (DTE) port
To view the LED status screen, follow this menu selection sequence:
Main Menu → Status → Display LEDs
main/status/leds
Device Name:
Model: 7510
DISPLAY LEDS
SYSTEM
ALARM TEST
NETWORK
DTE
OK
DM OOS OOF NS
TXD
RXD RTS CTS DTR
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
ESC for previous menu MainMenu Exit
Refresh
When viewed via the ATI, the status display screen is updated approximately
every 5 seconds. Use Refresh to obtain a current status of all LEDs.
November 1997
7510-A2-GB20-10
4-8
Monitoring the DSU
System LEDs
OK:
ON – DSU is operational.
OFF – DSU is performing a power-up self-test, has detected a system
failure, or there is no power.
ALARM:
ON – DSU has detected an alarm condition locally or from
the network. Refer to Troubleshooting in Chapter 6.
TEST:
ON – Test in progress. Test can be initiated locally, remotely,
or from the network. Includes power-up self-test.
System
Network
Port
496-15062
red
green
yellow
7510-A2-GB20-10
November 1997
4-9
Monitoring the DSU
Network LEDs
DM – Data Mode:
ON – DSU (DDS network interface) is sending or
receiving data, or is in DMI condition
(all 1s being received).
OFF – DDS network interface is receiving CMI codes.
OOS – Out of Service:
ON – DSU is receiving out of
service code from the remote unit.
Refer to Table 4-2, Health and Status
Messages.
OOF – Out of Frame:
ON – DSU is detecting an out of frame
condition. Refer to Table 4-2, Health
and Status Messages.
NS – No Signal:
ON – DDS network interface detects
no signal. Refer to Table 4-2,
Health and Status Messages.
System
Network
Port
496-15062
red
green
yellow
November 1997
7510-A2-GB20-10
4-10
Monitoring the DSU
Port LEDs
System
Network
Port
496-15062
red
green
yellow
TXD – Transmitted Data:
ON
OFF
– Receiving all 0s from the DTE.
– Receiving all 1s from the DTE.
Blinking – User data is being transferred.
RXD – Received Data:
ON
OFF
– Sending all 0s to the DTE.
– Sending all 1s to the DTE.
Blinking – User data is being transferred.
RTS – Request to Send:
ON – DTE is activating a control signal to
indicate readiness to transmit data.
CTS – Clear to Send:
ON – DSU is activating a control signal to
indicate to the DTE that it can start
sending data.
DTR – Data Terminal Ready:
ON – DTE is activating a control signal to
indicate readiness for operation.
7510-A2-GB20-10
November 1997
4-11
Testing
5
Accessing the Test Menu
From the Test menu, you can run network tests, data port tests, and a lamp test
for the front panel LEDs.
To access the Test menu, follow this menu selection sequence:
Main Menu → Test
main/test
Device Name:
Model: 7510
TEST
Network Tests
Data Port Tests
Lamp Test
Abort All Tests
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
Ctrl-a to access these functions
Exit
The DSU supports independent tests at the physical level.
H
H
The CSU and DSU loopbacks and 511 test pattern send/monitor are
supported on the network interface.
The Local Loopback and 511 test pattern send/monitor are supported on the
DTE port.
7510-A2-GB20-10
November 1997
5-1
Testing
Loopbacks can be started from a variety of points in the network, as shown in
Table 5-1.
Table 5-1. Device Messages
Loopback Type
Initiated By
Notes
Bilateral Loopback
H User
When enabled, running a DSU loopback
also automatically starts a local
loopback. Refer to Table A-3, Data Port
Options, to enable.
H Remote unit sending
V.54 sequence
CSU Loopback
H User (Network tests) When initiated by the network, CSU
Loopback cannot be disabled by the
H DDS Network, by
user.
loop current reversal
DSU Loopback
(Digital)
H User
Refer to Table A-3, Data Port Options.
Local Loopback
H User
H DTE via CT141
Control via CT141 can be disabled.
Refer to Table A-3, Data Port Options.
Network-initiated
56 kbps DSU
H DDS Network
Cannot be disabled by user.
Loopback (Non-
latching loopback)
Network-initiated
64 kbps CC DSU
Loopback
H DDS Network
Includes optional data scrambling and
uses 25-second timer to detect the
network sequence. Can be disabled by
user.
(Latching loopback)
Remote Digital
Loopback
H Remote unit sending Same as a DSU Loopback but initiated
V.54 sequence
by a remote unit via V.54 sequence.
Can be disabled locally. Refer to
Table A-2, Network Interface Options.
V.54 Sequences to
remote unit
H User
H DTE via CT140
Control via CT140 can be disabled.
Refer to Table A-3, Data Port Options.
November 1997
7510-A2-GB20-10
5-2
Testing
Running Network Tests
Network tests require the participation of your network service provider. To
access the Network Tests screen, follow this menu selection sequence:
Main Menu → Test → Network Tests
main/test/network
Device Name:
Model: 7510
NETWORK TESTS
Status
Test
Command
Result
0:00:00
CSU Loopback:
DSU Loopback:
Start
Start
Inactive
Inactive
0:00:00
Send V.54 Up:
Send
Sending
Send V.54 Down: Send
Inactive
Send 511:
Monitor 511:
Start
Stop
Inactive
Active
0:00:00
125:08:48
Errors 99999+
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
Ctrl-a to access these functions, ESC for previous menu
ResetMon
MainMenu
Exit
Use the Command column to start or stop a test by pressing Enter. The Result
column displays the test duration since the last device reset. When the Monitor
511 test is active, ResetMon is available to reset the error counter to zero.
7510-A2-GB20-10
November 1997
5-3
Testing
CSU or External Network Loopback
CSU loopback is an external loopback that is located as closely as possible to the
network interface.
" Procedure
To run a CSU loopback:
1. Position the cursor at the Start command next to CSU Loopback on the
Network Tests screen.
2. Press Enter.
3. The Start command is changed to Stop. If you want to manually stop the test,
verify that the cursor is positioned at the Stop command.
4. Press Enter. The duration of the test is displayed.
DSU
CSU
DDS
Network
Port
DTE
Interface
Aggregate
DTE
Port
496-15144
CSU Loopback
November 1997
7510-A2-GB20-10
5-4
Testing
DSU or Internal Network Loopback
DSU loopback is an internal loopback that is located as closely as possible to the
customer interface serving the DTE.
" Procedure
To run a DSU loopback:
1. Position the cursor at the Start command next to DSU Loopback on the
Network Tests screen.
2. Press Enter.
3. The Start command is changed to Stop. If you want to manually stop the test,
verify that the cursor is positioned at the Stop command.
4. Press Enter. The duration of the test is displayed.
DSU
CSU
Aggregate
DDS
Network
Port
DTE
Interface
DTE
Port
DSU Loopback
496-15160
Send V.54 Up/Down Sequences
The local DSU can send an ITU-T V.54 Up or Down sequence to request the
activation or termination of a DSU (digital) loopback of a remote unit. This is the
same as the DSU Loopback shown above except the test is activated remotely.
The DSU can send:
H
H
In-band V.54 Up (activation) code to request a Remote DSU Loopback
(V.54 Loop 2) at the remote DSU, or
In-band V.54 Down (deactivation) code to request the termination of a
Remote DSU Loopback (V.54 Loop 2) at the remote DSU.
" Procedure
To start or stop a remote DSU loopback:
1. Position the cursor at the Send command next to Send V.54 Up or Send V.54
Down on the Network Tests screen.
2. Press Enter.
Sending appears in the Status column followed (after 3 seconds) by
Command Complete at the bottom of the screen.
Refer to Running Network Tests on page 5-3 for an example of the Network
Tests screen.
7510-A2-GB20-10
November 1997
5-5
Testing
511 Test Pattern for the Network
This test sends or monitors the 511 test pattern over the network interface.
" Procedure
To run a Send 511 test:
1. Position the cursor at the Start command next to Send 511 on the Network
Tests screen.
2. Press Enter.
3. The Start command is changed to Stop. If you want to manually stop the test,
verify that the cursor is positioned at the Stop command.
4. Press Enter. The duration of the test is displayed.
" Procedure
To run a Monitor 511 test:
1. Position the cursor at the Start command next to Monitor 511 on the Network
Tests screen.
2. If desired, use Ctrl-a to switch to the screen function key area and use the
virtual function key r or R (ResetMon) to clear the error counter to zero. Press
Ctrl-a to return the cursor to the Start command.
3. Press Enter.
4. The Start command is changed to Stop. If you want to manually stop the test,
verify that the cursor is positioned at the Stop command.
5. Press Enter. The duration of the test is displayed.
Refer to Running Network Tests on page 5-3 for an example of the Network
Tests screen.
November 1997
7510-A2-GB20-10
5-6
Testing
Running Data Port Tests
For an example of the fields on a test menu screen, refer to Running Network
Tests on page 5-3. To access the Data Port Tests screen, follow this menu
selection sequence:
Main Menu → Test → Data Port Tests
main/test/port
Device Name: Node A
Model: 7510
DATA PORT TESTS
Test
Command
Start
Status
Result
Local Loopback:
Inactive
000:00:00
Send 511:
Monitor 511:
Start
Stop
Inactive
Active
000:00:00
255:59:59+ – Errors 99999+
–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
Ctrl–a to access these functions, ESC for previous menu
ResetMon
MainMenu
Exit
7510-A2-GB20-10
November 1997
5-7
Testing
Local Loopback
Local Loopback loops the user data back to the DTE. This loopback is located as
closely as possible to the User Data Port (DTE) interface.
" Procedure
To run a local loopback:
1. Position the cursor at the Start command next to Local Loopback on the Data
Port Tests screen.
2. Press Enter.
3. The Start command is changed to Stop. If you want to manually stop the test,
verify that the cursor is positioned at the Stop command.
4. Press Enter. The duration of the test is displayed.
DSU
CSU
DDS
Network
Port
DTE
Interface
DTE
Port
Aggregate
496-15145
Local Loopback
511 Test Pattern for the DTE
This test sends or monitors a 511 test pattern over the User Data Port interface.
" Procedure
To run a Send 511 test:
1. Position the cursor at the Start command next to Send 511 on the Data Port
Tests screen.
2. Press Enter.
3. The Start command is changed to Stop. If you want to manually stop the test,
verify that the cursor is positioned at the Stop command.
4. Press Enter. The duration of the test is displayed.
November 1997
7510-A2-GB20-10
5-8
Testing
" Procedure
To run a Monitor 511 test:
1. Position the cursor at the Start command next to Monitor 511 on the Data
Port Tests screen.
2. If desired, use Ctrl-a to switch to the screen function key area and use the
virtual function key r or R (ResetMon) to clear the error counter to zero. Press
Ctrl-a to return the cursor to the Start command.
3. Press Enter.
4. The Start command is changed to Stop. If you want to manually stop the test,
verify that the cursor is positioned at the Stop command.
5. Press Enter. The duration of the test is displayed.
The 511 monitor expects the external equipment to provide the clock for the
511 pattern on the interchange circuit CT113 (TT), for timing the incoming pattern.
Refer to V.35 User Data Port Connector in Appendix C, Cables and Pin
Assignments.
Running the Lamp Test
The DSU supports a Lamp test from the Test menu to determine whether all
LEDs light up.
During the Lamp test, all LEDs blink simultaneously once per second. When you
stop the Lamp test, the LEDs are restored to their normal condition.
To access the Data Port Tests screen, follow this menu selection sequence:
Main Menu → Test → Lamp Test
" Procedure
To run a Lamp test:
1. Position the cursor at the Start command next to Lamp Test on the Lamp Test
screen.
2. Press Enter.
3. The Start command is changed to Stop. When you want to stop the test,
verify that the cursor is positioned at the Stop command.
4. Press Enter.
7510-A2-GB20-10
November 1997
5-9
Testing
Ending an Active Test
A test initiated by the user can be ended by the user.
H
A Test Timeout option is available to automatically terminate a user-initiated
Loopback or Pattern test after it has been running a specified period of time.
Refer to Table A-1, System Options.
Test Timeout does not pertain to tests commanded by the:
— Network, such as the network-initiated CSU and DSU Loopbacks.
— DTE, such as the DTE-initiated Local Loopback.
H
H
On each test screen is a command column. Pressing Return when the cursor
is on the Stop command stops the test.
Use the Abort All Tests selection from the Test menu to stop all tests running
on all interfaces, with the exception of network or DTE-initiated loopbacks.
Command Complete appears when all tests on all interfaces have been
terminated.
November 1997
7510-A2-GB20-10
5-10
Messages and Troubleshooting
6
Messages and Troubleshooting
There are many messages available to assess the status of the device and
contribute to problem resolutions. Refer to the following sections:
H
H
Responding to Device Messages
Troubleshooting
Responding to Device Messages
The Device Messages in Table 6-1, listed in alphabetical order, may appear in the
messages area at the bottom of the ATI screens.
Table 6-1. Device Messages (1 of 2)
Device Message
What Message Indicates
What To Do
Command Complete
Action requested has
successfully completed.
No action needed.
Invalid Character x
A nonprintable ASCII
character has been
entered.
Reenter information using valid
characters.
Invalid – Network
Network-initiated loopback
No action needed.
Initiated CSU (or DSU) was in progress when
Loopback Active
another selection was
made.
Invalid – [Test]
Already Active
[Test] can be a CSU, DSU,
or DTE Local Loopback, or
a Send 511 or Monitor 511.
The [test] was already in
progress when another
selection was made.
H Allow test to continue.
H Select another test.
H Stop the test.
7510-A2-GB20-10
November 1997
6-1
Messages and Troubleshooting
Table 6-1. Device Messages (2 of 2)
Device Message
What Message Indicates
What To Do
Invalid Test
Combination
A loopback or 511 pattern
test was in progress when
Start was selected to start
another test, or was active
on the same or another
interface when Start was
selected.
H Wait until other test ends and
message clears.
H Abort all tests from the Test
menu screen.
H Stop the test from the same
screen the test was started
from.
Please Wait
Test Active
Command takes longer
than 5 seconds.
Wait until message clears.
A test is running and no
higher priority health and
status messages exist.
H Contact service provider if test
initiated by the network.
H Wait until the other test ends
and message clears.
H Cancel all tests from the Test
screen.
H Stop the test from the same
screen the test was started
from.
November 1997
7510-A2-GB20-10
6-2
Messages and Troubleshooting
Troubleshooting
This DSU is designed to provide you with many years of trouble-free service. If a
problem occurs, however, refer to Table 6-2 for possible solutions.
Table 6-2. Troubleshooting (1 of 2)
Symptom
Possible Cause
Solutions
Alarm LED is on.
One of several alarm
conditions exists. Health
and Status displays the
alarm condition.
Refer to Table 4-2, Health and
Status Messages, for
recommended action.
Cannot access the
DSU via the ATI.
The terminal is not set up
for the correct rate or data
format, or the DSU is
configured so it prevents
access.
H Check the cable and
connections.
H Set up your terminal or PC
emulation as shown in
Connecting to the Terminal Port
in Chapter 2.
H Power the DSU on and off and
try again.
Device Fail appears The DSU detects an
H Power the DSU off and on and
on the System and
Test Status screen
under Self-Test
results.
internal hardware failure.
try again.
H Contact your service
representative.
An LED is not lit.
LED is burned out.
Run the Lamp test. If the LED in
question does not flash with the
other LEDs, then contact your
service representative.
No power, or the
LEDs are not lit.
The power cord is not
Check that the power cord is
securely attached at both ends.
securely plugged into the
wall receptacle and into the
rear panel connection.
The wall receptacle has no
power.
H Check the wall receptacle power
by plugging in some equipment
that is known to be working.
H Check the circuit breaker.
H Verify that your site is not on an
energy management program.
Power supply has failed.
Replace power supply.
7510-A2-GB20-10
November 1997
6-3
Messages and Troubleshooting
Table 6-2. Troubleshooting (2 of 2)
Symptom Possible Cause
Solutions
Not receiving data;
DSU is not
H DDS line rate/speed has H Verify that your subscriber loop is
changed.
running at 56 or 64 CC kbps.
responding.
H Excessive BPVs causing
DSU to become stuck in
Autobaud mode.
H Verify that the DSU is set to the
same rate as your subscriber
loop. (The DSU’s rate is
displayed on the Network
Interface Status screen.)
H Excessive Loop Loss
causing DSU to become
stuck in Autobaud mode.
H If getting Excessive BPVs, verify
that you do not have a bad cable.
If the cable is good, contact the
network provider.
H If getting excessive Loop Loss
(dB) indications, install a higher
quality cable. Refer to Table D-2,
Model 7510 DSU LADS
Connection Distances, in
Appendix D.
H If the DDS Line Rate (Kbps) field
shows Autobaud, the DSU may
be stuck in Autobaud mode.
Configure Line Rate (Kbps) for
56 or 64 kbps.
H Run Loopback tests. Refer to
Running Network Tests in
Chapter 5.
Power-Up Self-Test The DSU has detected an
H Reset the DSU and try again.
fails. Only Alarm
LED is on after
power-up.
internal hardware failure.
H Contact your service
representative.
Resetting the DSU
The DSU can be reset locally or remotely.
To reset the DSU, follow this menu selection sequence:
Main Menu → Control → Reset Device
The DSU reinitializes itself, performing a Device Self-Test. Refer to Table 4-3,
Self-Test Results Messages.
Displaying DSU Identity Information
To display the DSU’s system name, location, contact, serial number, model
number, and software and hardware revision numbers, follow this menu selection
sequence:
Main Menu → Status → Identity
November 1997
7510-A2-GB20-10
6-4
Configuration Option Tables
A
Overview
The tables in this appendix summarize the configuration options accessed when
you select Configuration on the Main Menu. The configuration options are
arranged into groups based upon functionality.
Select . . .
To Access the . . .
To Configure the . . .
System
System Options, Table A-1
General system
options.
Network
Network Interface Options, Table A-2
Data Port Options, Table A-3
DDS network interface.
User data on DTE port.
ATI.
Data Port
Terminal Port
Terminal Port Options, Table A-4
NOTE:
All changes to configuration options must be saved. Refer to Saving
Configuration Options in Chapter 3.
MAIN MENU
Status
Test
Configuration
Control
Configuration
Edit/Display
• System
Load
Configuration
From ...
• Network
• Data Port
• Terminal Port
497-15239
7510-A2-GB20-10
November 1997
A-1
Configuration Option Tables
System Options Menu
For System Options, refer to Table A-1. To access the System Options screen,
follow this menu selection sequence:
Main Menu → Configuration (Load Configuration From) →
Configuration Edit/Display → System
Table A-1. System Options (1 of 2)
Operating Mode
Possible Settings: DDS, LADS
Default Setting: DDS
The unit’s operating mode depends upon the DSU’s application.
DDS – Standard DDS network operation. The operating rate is either 56 kbps or
64 kbps CC.
LADS – The Local Area Data Set operating mode requires that the local and remote
units are connected directly to each other. This is a point-to-point application; also
known as LDM.
DDS Line Rate (Kbps)
Possible Settings: 56, 64CC, Autobaud
Default Setting: Autobaud
The unit starts up with Autobaud. When the DDS line rate obtained from the service
provider is detected, Autobaud is replaced with the actual rate.
H DDS Line Rate (Kbps) option appears when Operating Mode is set to DDS.
NOTE: Setting the actual data rate will result in minimum power-up time. (If both
DSUs use Autobaud, training can take several minutes.) Configuring the
actual data rate is recommended after initial installation.
56 – 56 kbps line rate.
64CC – 64 kbps Clear Channel on a 72 kbps circuit.
Autobaud – This setting is automatically changed to the actual operating line rate of
56 kbps or 64CC as soon as the signal is detected.
LADS Timing
Possible Settings: Internal, External, Receive
Default Setting: Internal
Determines the timing source for the unit.
H LADS Timing option appears when Operating Mode is set to LADS.
Internal – Timing derived from the unit’s local clock. Use this setting for the LADS
primary timing unit that establishes the timing for both point-to-point units.
External – Timing is derived from the external clock provided by the DTE connected to
the V.35 interface on circuit CT113 (pins U, W).
Receive – Timing is derived from the line receive signal unless the unit is running
diagnostic tests. During the tests, the timing source is the internal clock. This setting
should be used for a LADS secondary timing unit.
November 1997
7510-A2-GB20-10
A-2
Configuration Option Tables
Table A-1. System Options (2 of 2)
LADS Line Rate (Kbps)
Possible Settings: 56, 64
Default Setting: 64
Line operating rate for LADS operation.
H LADS Line Rate (Kbps) option appears when Operating Mode is set to LADS.
56 – 56 kbps line rate. Provides increased distance for the LADS applications.
64 – 64 kbps line rate.
Test Timeout
Possible Settings: Enable, Disable
Default Setting: Enable
Allows user-initiated tests to end automatically. Recommend enabling when the unit is
managed remotely through the IMC to avoid the requirement to terminate the test
manually.
Enable – User-initiated loopback and pattern tests end when test duration is reached.
Disable – Tests must be terminated manually from the Network Tests screen. Refer to
Running Network Tests in Chapter 5.
NOTE: Tests commanded by the DTE or network-initiated tests are not affected by
this test timeout.
Test Duration (min)
Possible Settings: 1–120
Default Setting: 10
Number of minutes for a test to be active before automatically ending.
H Test Duration (min) option appears when Test Timeout is enabled.
1 to 120 – Amount of time in minutes for a user-initiated test to run before terminating.
7510-A2-GB20-10
November 1997
A-3
Configuration Option Tables
Network Interface Options Menu
For Network Interface Options, refer to Table A-2. To access the Network
Interface Options screen, follow this menu selection sequence:
Main Menu → Configuration (Load Configuration From) →
Configuration Edit/Display → Network
Table A-2. Network Interface Options
Network-initiated DSU Loopback (64K CC)
Possible Settings: Enable, Disable
Default Setting: Enable
Indicates whether the access unit responds to a DSU latching loopback sequence sent
by the network as specified by TR62310.
H Network-initiated DSU Loopback (64K CC) option appears when Operating Mode
is set to DDS in Table A-1.
Enable – Responds to network-initiated commands to start and stop a latching DSU
loopback.
Disable – DSU will not respond to a DSU loopback initiated by the network.
Data Scrambling (64K CC)
Possible Settings: Enable, Disable
Default Setting: Disable
Data scrambling is used to suppress the possible simulation of network-initiated DSU
latching loopback commands by application data.
H Data Scrambling (64K CC) option appears when Operating Mode is set to DDS in
Table A-1.
Enable – Enables data scrambling. The local and remote units must be set the same.
Disable – No data scrambling.
V.54 Initiated DSU Loopback
Possible Settings: Enable, Disable
Default Setting: Disable
When enabled, user data is looped back to the network when a V.54 Loop Up sequence
is received. The DSU loopback ends when a V.54 Loop Down sequence is detected.
Enable – DSU loopback can be initiated or terminated by a remote unit sending in-band
V.54 Loop 2 Up or Down sequences.
Disable – V.54 Loop 2 sequences are ignored.
November 1997
7510-A2-GB20-10
A-4
Configuration Option Tables
Data Port Options Menu
For Data Port Options, refer to Table A-3. To access the Data Port Options
screen, follow this menu selection sequence:
Main Menu → Configuration (Load Configuration From) →
Configuration Edit/Display → Data Port
Table A-3. Data Port Options (1 of 3)
Invert Transmit Clock
Possible Settings: Enable, Disable
Default Setting: Disable
The DSU clock provided on Interchange Circuit CT114, Transmit Signal Element Timing
DCE source (TXC), is phase inverted with respect to Interchange Circuit CT103,
Transmitted Data (TXD). Recommended when data errors are occurring due to long
cable lengths.
Enable – The DSU-supplied clock is phase inverted with respect to the transmitted data
TXD.
Disable – The clock supplied by the DSU on TXC is normal (i.e., not inverted).
Port (DTE) Initiated Loopbacks
Possible Settings: Disable, Local, Remote, Both
Default Setting: Disable
Specifies whether the DTE can initiate and terminate local and/or remote loopbacks.
The DTE loopback control is done through the Interchange Circuits specified by the
V.54 standard.
NOTE: Refer to Running Network Tests in Chapter 5.
Disable – No local or remote loopbacks can be initiated by the DTE.
Local – A local loopback can be controlled by the DTE, via the Interchange Circuit LL
(CT141), as specified by V.54. The DTE port remains in loopback as along as LL
remains on. Aborting the loopback from the ATI has no effect.
Remote – A remote digital loopback can be controlled by the DTE, via Interchange
Circuit RL (CT140), as specified by V.54. The remote equipment must be able to detect
the in-band V.54 loopback sequence.
Both – Both the local and remote loopbacks can be controlled by the DTE.
Bilateral Loopback
Possible Settings: Enable, Disable
Default Setting: Disable
When a DSU loopback is initiated, a local DTE loopback is also automatically initiated.
A Bilateral Loopback can be started by the ATI/NMS or by detection of a V.54 Loop 2 Up
sequence.
Enable – When Bilateral Loopback is enabled, running a DSU loopback also
automatically starts a local loopback. The local loopback ends when the DSU loopback
terminates.
Disable – Running a DSU loopback does not start a local loopback.
NOTE: Refer to Running Network Tests in Chapter 5.
7510-A2-GB20-10
November 1997
A-5
Configuration Option Tables
Table A-3. Data Port Options (2 of 3)
Carrier Control by RTS
Possible Settings: Constant, Switched
Default Setting: Constant
Simulates Constant or Switched Carrier operation.
Constant – The internal RTS is forced on and the DSU is in a constant Data Mode on
the transmit line. The external RTS lead is ignored. The actual signal on the line is either
all ones (DMI) or DTE transmitted data.
Switched – RTS is monitored and CMI codes are transmitted when RTS is off.
CTS Control
Possible Settings: Standard, Follow RTS, Forced On, Circuit Assurance
Default Setting: Standard
Specifies the operation of the Interchange Circuit CT106, Clear to Send (CTS), which is
an output from the DSU.
Standard – CTS follows the internal RTS with a fixed delay, except that CTS will be off
when a network interface related alarm is detected or a test is active. The active test
may be initiated locally, remotely, or by the network.
Follow RTS – CTS follows the external RTS lead without delay, regardless of alarms
and tests.
Forced On – CTS is always forced on after the unit is powered up with a successful
self-test.
Circuit Assurance – With circuit assurance, CTS operates the same as the Standard
option, except that CTS will also be deasserted when CMI codes are being received.
RLSD Control
Possible Settings: Standard, Forced On
Default Setting: Standard
Specifies the operation of the Interchange Circuit CT109, Received Line Signal Detector
(RLSD or CD), which is an output from the DSU.
Standard – RLSD is asserted when Data Mode is on the receive line. RLSD deasserts
when a DDS facility alarm is detected or the DSU is receiving CMI codes.
Forced On – RLSD is forced on after the unit is powered up with a successful self-test.
DSR Control
Possible Settings: Standard, Forced On, On During Test
Default Setting: Standard
Specifies the operation of the Interchange Circuit CT107, Data Set Ready (DSR), which
is an output from the DSU.
Standard – DSR is always asserted, except when a DDS facility alarm is reported or
the DSU is in Test mode.
Forced On – DSR is forced on after the unit is powered up with a successful self-test.
On During Test – DSU operates the same as the Standard option, except that DSR
remains asserted when the DSU is in Test mode to allow the DTE to send test patterns.
November 1997
7510-A2-GB20-10
A-6
Configuration Option Tables
Table A-3. Data Port Options (3 of 3)
Monitor DTR
Possible Settings: Enable, Disable
Default Setting: Enable
Indicates to the DSU whether to monitor the Interchange Circuit CT108, Data Terminal
Ready (DTR), from the DTE.
Enable – The DSU monitors the state of DTR on the DTE port and displays it on the
System and Test Status screen.
Disable – DTR is not monitored by the DSU. Use when a DTE does not provide the
DTR lead at the interface.
Terminal Port Options
For Terminal Port options, refer to Table A-4. To access the Terminal Port Options
screen, follow this menu selection sequence:
Main Menu → Configuration (Load Configuration From) →
Configuration Edit/Display → Terminal Port
Table A-4. Terminal Port Options (1 of 2)
Monitor DTR
Possible Settings: Enable, Disable
Default Setting: Enable
Specifies monitoring of the Data Terminal Ready (DTR) control lead.
Enable – Standard operation of the DTR control lead.
Disable – DTR is ignored. Some external device connections may require this setting.
Inactivity Timeout
Possible Settings: Enable, Disable
Default Setting: Disable
Provides automatic logoff of an ATI session through the Terminal Port. When the
session is closed, User Interface Idle appears on the screen and the unit toggles the
Terminal port DSR lead.
Enable – The ATI session terminates automatically after the Disconnect Time set in the
next option. When the session was occurring over an external modem connected to the
Terminal port, the modem will interpret the DSR toggle as DTR being dropped and
disconnect.
Disable – An ATI session through the Terminal port will remain active indefinitely.
7510-A2-GB20-10
November 1997
A-7
Configuration Option Tables
Table A-4. Terminal Port Options (2 of 2)
Disconnect Time(minutes)
Possible Settings: range 1 – 60
Default Setting: 5
Number of minutes of inactivity before the ATI session terminates automatically.
Timeout is based on no keyboard activity.
H Disconnect Time(minutes) option appears when Inactivity Timeout is enabled.
1 to 60 – The ATI user session is closed after the selected number of minutes.
November 1997
7510-A2-GB20-10
A-8
Worksheets
B
Overview
The worksheets in this appendix summarize the configuration options accessed
when you select Configuration on the Main Menu. The possible menu selections
are displayed with the default settings and the possible settings.
Configuration Worksheets
System
Configuration Option
Operating Mode
DDS Line Rate (Kbps)
LADS Timing
Settings
Default in [Bold]
[DDS], LADS
56, 64CC, [Autobaud]
[Internal], External, Receive
56, [64]
LADS Line Rate (Kbps)
Test Timeout
[Enable], Disable
1–120, [10]
Test Duration (min)
7510-A2-GB20-10
November 1997
B-1
Worksheets
Network Interface
Configuration Option
Settings
Default in [Bold]
Network-initiated DSU Loopback (64K CC) [Enable], Disable
Data Scrambling (64K CC)
V.54 Initiated DSU Loopback
Enable, [Disable]
Enable, [Disable]
Data Port
Configuration Option
Invert Transmit Clock
Port (DTE) Initiated Loopbacks
Bilateral Loopback
Carrier Control by RTS
CTS Control
Settings
Default in [Bold]
Enable, [Disable]
[Disable], Local, Remote, Both
Enable, [Disable]
[Constant], Switched
[Standard], Follow RTS, Forced On,
Circuit Assurance
RLSD Control
DSR Control
Monitor DTR
[Standard], Forced On
[Standard], Forced On, On During Test
[Enable], Disable
Terminal Port
Configuration Option
Monitor DTR
Settings
Default in [Bold]
[Enable], Disable
Enable, [Disable]
range 1 – 60 [5]
Inactivity Timeout
Disconnect Time(minutes)
November 1997
7510-A2-GB20-10
B-2
Cables and Pin Assignments
C
Overview
The following sections provide pin assignments for the:
H
Terminal Port EIA-232 Connector
V.35 User Data Port Connector
H
H
H
H
Standard EIA-232-D Crossover Cable
LAN Adapter Converter and Cable
Modular RJ48S DDS Network Interface Cable
7510-A2-GB20-10
November 1997
C-1
Cables and Pin Assignments
Terminal Port EIA-232 Connector
The Terminal port connects to a PC or VT100-compatible terminal.
Signal
Direction
Pin #
Transmit Data (TXD)
Received Data (RXD)
Request to Send (RTS)
Clear to Send (CTS)
Data Set Ready (DSR)
Signal Ground (SG)
Carrier Detect (CD)
To DSU (In)
From DSU (Out)
To DSU (In)
From DSU (Out)
From DSU (Out)
—
2
3
4
5
6
7
From DSU (Out)
8
Data Terminal Ready (DTR) To DSU (In)
20
November 1997
7510-A2-GB20-10
C-2
Cables and Pin Assignments
V.35 User Data Port Connector
The following table provides the pin assignments for the 34-position
V.35 connector to the User Data terminal equipment.
34-Pin
Socket
Connector
ITU CT
Number
Signal
Direction
Signal Ground/Common
Request to Send (RTS)
Clear to Send (CTS)
Data Set Ready (DSR)
102
—
B
C
D
E
F
105
To DSU (In)
From DSU (Out)
From DSU (Out)
From DSU (Out)
106
107
Received Line Signal Detector
(RLSD or LSD)
109
Data Terminal Ready (DTR)
Remote Loopback (RL)
Local Loopback (LL)
108/1, /2 To DSU (In)
H
N
L
140
141
103
To DSU (In)
To DSU (In)
To DSU (In)
Transmitted Data (TXD)
P (A)
S (B)
Received Data (RXD)
104
113
115
114
142
From DSU (Out)
To DSU (In)
R (A)
T (B)
Transmitter Signal Element Timing –
DTE Source (XTXC or TT)
U (A)
W (B)
Receiver Signal Element Timing –
DCE Source (RXC)
From DSU (Out)
From DSU (Out)
From DSU (Out)
V (A)
X (B)
Transmitter Signal Element Timing –
DCE Source (TXC)
Y (A)
AA (B)
Test Mode Indicator (TM)
NN
7510-A2-GB20-10
November 1997
C-3
Cables and Pin Assignments
Standard EIA-232-D Crossover Cable
A standard crossover cable can be used to connect the Terminal port to an
external modem.
Pin 14
Pin 1
Pin 1
P1
Plug
P2
Plug
Pin 14
Pin 25
Pin 13
Pin 25
Pin 13
P1
Pin
Pin
P2
Chassis Ground
Chassis Ground
1
2
1
TXD
RXD
RTS
TXD
RXD
RTS
2
3
3
4
4
5
5
DSR
DSR
Signal Ground
CD (RLSD)
6
6
Signal Ground
CD (RLSD)
7
7
8
8
9
9
10
11
12
13
14
15
16
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
RXC
DTR
RXC 17
18
19
DTR 20
21
22
23
XTXC
XTXC 24
25
97-15180-01
November 1997
7510-A2-GB20-10
C-4
Cables and Pin Assignments
LAN Adapter Converter and Cable
The following figure shows the pin assignments for the:
H
H
DB25 plug to modular jack converter between the Management port and the
8-conductor LAN Adapter cable, and
Custom 8-conductor cable (with modular plugs on both ends) between the
converter and the LAN Adapter.
Plug-to-Modular
Jack Converter
Cable
Management
8-Position
Plug to
Plug to
Port (DB25 Plug)
Modular Jack
Modular Jack
LAN Adapter
Tx Clock 15
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
Unused
Rx Data
3
7
2
DTR
Signal Ground
Tx Data
Tx Data
Signal Ground
Rx Data
CTS
DTR 20
CD
8
4
RTS
Frame Ground
Unused
Rx Clock 17
496-15179
Modular RJ48S DDS Network Interface Cable
Network access is via a 14-foot modular cable with an RJ48S keyed plug
connector on each end.
RJ48S DDS Network
Interface Cable Functions
Circuit Pin #
Transmitted data to the local loop
Transmitted data to the local loop
Received data from the local loop
Received data from the local loop
R
T
1
2
7
8
T1
R1
7510-A2-GB20-10
November 1997
C-5
Technical Specifications
D
Table D-1. Model 7510 DSU Technical Specifications (1 of 2)
Item
Specifications
Housing
Height (including feet)
Height (without feet)
Width
2.1 inches (5.3 cm)
2.0 inches (5.1 cm)
8.7 inches (22.1 cm)
6.2 inches (15.7 cm)
Depth (case)
Depth (case and connectors) 6.5 inches (16.5 mm)
Weight
Power
1.3 pounds (0.6 kg)
Normal service voltage
range
Input: 120 Vac +12 Vac, 60 Hz +3 Hz
4.9 watts (max.) at 120 Vac
Approvals
FCC Part 15
FCC Part 68
Safety Certifications
Emissions
Class A digital device
Refer to the equipment’s label for Registration Number.
Refer to the equipment’s label for approvals on product.
Class A digital apparatus
Interface and Connectors
25-pin D-subminiature
connector
EIA-232/ ITU V.24 (ISO 2110) for Terminal Port
ITU V.35 (ISO 2593) for DTE Port
34-pin MS34 connector
Physical Environment
Operating Temperature
Storage Temperature
Relative Humidity
32° to 122° F (0° to 50° C)
–4° to 158° F (–20° to 70° C)
5%—95% (noncondensing)
Shock and Vibration
Withstands normal shipping and handling
Heat Dissipation
11.6 Btu/hr. (max.) at 120 Vac
7510-A2-GB20-10
November 1997
D-1
Technical Specifications
Table D-1. Model 7510 DSU Technical Specifications (2 of 2)
Item
Specifications
Network Interface
Data rates
56 kbps and 64 kbps clear channel (CC)
56 kbps and 64 kbps
LADS data rates
Services supported
4-wire service
Network Compatibility
ANSI T1.410-1992 and
AT&T Technical Reference
62310-1993
56 and 64 kbps meeting desired loop loss
34-pin V.35 connector
DTE Data Port Interface
Table D-2. Model 7510 DSU LADS Connection Distances
Wire Diameter (AWG)
19 Gauge
(.0359I or
.9122 mm)
22 Gauge
(.0253I or
.643 mm)
24 Gauge
(.0201I or
.511 mm)
26 Gauge
(.0159I or
.404 mm)
Data Rate
(kbps)
56
10.84 mi
6.4 mi
4.50 mi
3.34 mi
(17.45 km)
(10.3 km)
(7.24 km)
(5.37 km)
64
10.69 mi
6.06 mi
4.47 mi
3.20 mi
(17.2 km)
(9.76 km)
(7.2 km)
(5.15 km)
November 1997
7510-A2-GB20-10
D-2
Glossary
aggregate
ASCII
A single bit stream that combines two or more bit streams.
American Standard Code for Information Interchange. A 7-bit code that establishes
compatibility between data services. ASCII is the standard for data transmission over
telephone lines.
ASCII Terminal or
Printer
Devices that can be attached, either locally or remotely, to display or print the DSU’s alarm
messages.
asynchronous
A data transmission that is synchronized by a transmission start bit at the beginning of
a character (five to eight bits) and one or more stop bits at the end.
AT Command Set
Attention Command Set. A group of commands, issued from an asynchronous DTE, that
allows control of the modem while in Command mode. All commands must begin with the
characters AT and end with a carriage return.
ATI
Asynchronous terminal interface. This feature allows a device to be controlled from an
async (asynchronous) terminal like an ASCII (VT100-compatible) terminal.
autobaud mode
An operational mode in which the DSU forces automatic setting of the DDS line rate/speed
(56 or 64 kbps) as soon as a valid DDS network signal is detected.
AUX port
BPV
The auxiliary communications port on a router.
Bipolar Violation. A modified bipolar signaling method in which a control code is inserted.
Circuit Card Assembly. A printed circuit board to which separate components are attached.
Consultative Committee on International Telegraphy and Telephony. See ITU.
CCA
CCITT
CD
Carrier Detect. A signal indicating that energy exists on the transmission circuit.
Associated with Pin 8 on an EIA-232 interface.
channel
CMI
An independent data path.
Control Mode Idle. A control signal sent over the DDS line to indicate that no data is being
sent.
COM port
Communications port. A computer’s serial communications port used to transmit to and
receive data from a DCE. The DCE connects directly to this port.
configuration option
CPE
Device software that sets specific operating parameters for the DSU.
Customer Premises Equipment. Terminating equipment supplied by either the customer or
some other supplier that is connected to the telecommunications network (e.g., DSUs,
terminals, phones, routers, modems).
CSU
CTS
DCE
Channel Service Unit. The function of the DSU that protects the T1 line from damage and
regenerates the T1 signal.
Clear to Send. An EIA-lead standard for V.24 circuit CT 106; an output signal
(DCE-to-DTE).
Data Communications Equipment. The equipment that provides the functions required to
establish, maintain, and end a connection. It also provides the signal conversion required
for communication between the DTE and the network.
DDS
Digital Data Service. Provides digital communication circuits.
7510-A2-GB20-10
November 1997
GL-1
Glossary
DMI
DSR
DSU
DTE
DTR
EIA
Data Mode Idle. Refers to a sequence of ones transmitted or received on the DDS
network.
Data Set Ready. An EIA-lead standard for V.24 circuit CT 107; an output signal
(DCE-to-DTE).
Data Service Unit. Data communications equipment that provides an interface between the
DTE and the digital network.
Data Terminal Equipment. The equipment, such as computers and printers, that provides
or creates data.
Data Terminal Ready. An EIA-lead standard for V.24 circuit CT 108; an input signal
(DTE-to-DCE).
Electronic Industries Association. This organization provides standards for the data
communications industry to ensure uniformity of interface between DTEs and DCEs.
EIA-232
The EIA’s standards defining the 25-pin interface between the DTE and DCE.
excessive BPV
An excessive bipolar violation condition results when at least one invalid bipolar violation
has occurred every 20 milliseconds for 2 seconds.
factory defaults
FCC
A predetermined set of configuration options for general operation.
Federal Communications Commission. Board of Commissioners that regulates all U.S.
interstate, intrastate, and foreign electrical communication systems that originate from the
United States.
frame relay
A switching interface that is designed to get frames from one part of the network to another
as quickly as possible.
full-duplex
HDLC
The capability to transmit in two directions simultaneously.
High-Level Data Link Control. A communications protocol defined by the International
Standards Organization (ISO).
interface
ITU
A shared boundary between functional units.
International Telecommunication Union, formerly known as CCITT. An advisory committee
established by the United Nations to recommend communications standards and policies.
LADS
Local Area Data Set is used to provide a point-to-point link between two devices (also
called LDM – limited distance modem).
LAN
Local Area Network. A network designed to connect devices over short distances, like
within a building.
latching loopback
LED
A latching loopback can only be initiated or terminated by the 64 kbps clear channel
network service provider.
Light Emitting Diode. A status indicator that responds to the presence of a certain
conditions.
link layer protocol
LL
The protocol that regulates the communication between two network nodes.
Local Loopback. An EIA-lead standard for V.24 circuit CT 141; an input signal
(DTE-to-DCE).
loopback
LSD
Used to test various portions of a data link in order to isolate an equipment or data line
problem. A diagnostic procedure that sends a test message back to its origination point.
Line Signal Detect. An EIA-lead standard for V.24 circuit CT 109; an output signal
(DCE-to-DTE).
November 1997
7510-A2-GB20-10
GL-2
Glossary
multiplexing
node
A method for interleaving several access channels onto a single circuit for transmission
over the network.
A connection or switching point on the network.
non-latching
loopback
A non-latching loopback can only be initiated or terminated by the 56 kbps network service
provider.
NS
No Signal. A network-reported condition.
OOF
Out Of Frame. An error condition in which frame synchronization bits are in error. A
network-reported condition.
OOS
Out of Service. A digital network trouble signal.
Packet Assembler/Disassembler.
PAD
point-to-point circuit
protocol
A data network circuit with one control and one tributary device.
The rules that govern how devices exchange information on a network. It covers timing,
format, error control, and flow control during data transmission.
PSTN
Public Switched Telephone Network. A network shared among many users who can use
telephones to establish connections between two points.
reset
A reinitialization of the device that occurs at power-up or in response to a reset command.
Routing Information Protocol. Specifies the routing protocol used between DSUs.
Receive Line Signal Detect. See CD.
RIP
RLSD
router
A device that makes decisions about the paths network traffic should take and forwards
that traffic to its destination. A router helps achieve interoperability and connectivity
between different vendor’s equipment, regardless of protocols used.
RS-232
RTS
An EIA standard for the 25-pin DCE/DTE interface. Same as EIA-232.
Request to Send. An EIA-lead standard for V.24 circuit CT 105; an input signal
(DTE-to-DCE).
RXC
RXD
Received Clock. An EIA-lead standard for V.24 circuit CT 115; an output signal
(DCE-to-DTE).
Received Data. An EIA-lead standard for V.24 circuit CT 104; an output signal
(DCE-to-DTE).
SDLC
Synchronous Data Link Control. A standard data link protocol.
synchronous
Data transmission that is synchronized by timing signals. Characters are sent at a fixed
rate.
TDM
Time Division Multiplexer. A device that enables the simultaneous transmission of multiple
independent data streams into a single high-speed data stream.
TM
Test Mode. An EIA-lead standard for V.24 circuit CT 142; an output signal (DCE-to-DTE).
TXC
Transmit Clock. An EIA-lead standard for V.24 circuit CT 114; an output signal
(DCE-to-DTE).
TXD
Transmit Data. An EIA-lead standard for V.24 circuit CT 103; an input signal
(DTE-to-DCE).
V.35
ITU-T standard for a high-speed, 34-pin, DCE/DTE interface.
WAN
Wide Area Network. A network that operates over long distances and spans a relatively
large geographic area (e.g., a country).
7510-A2-GB20-10
November 1997
GL-3
Index
Numbers
D
device
A
alarm
ATI
displaying
E
C
effective access, to ATI, 2-3
configuration
F
G
glossary, GL-1–GL-4
7510-A2-GB20-10
November 1997
IN-1
Index
H
N
hardware revision number, 6-4
network
I
interface
connections, 1-4
K
O
options
L
LADS (Local Area Data Set)
overview
P
problems
M
messages
November 1997
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IN-2
Index
R
T
rear panel, connections, 1-4
terminal port
test
S
safety instructions. See Start-Up Instructions
U
software revision number, 6-4
status
V
W
system
7510-A2-GB20-10
November 1997
IN-3
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