This document describes the Integrated Services Digital Network (ISDN) interface. It includes the following topics:
ISDN Overview
ISDN Hardware Configurations
Before You Begin
Displaying the ISDN Configuration Prompt
Configuration Procedures
Configuring Point-to-Point ISDN
Configuring Multipoint ISDN
Displaying the ISDN Monitoring Prompt
ISDN Commands
ISDN Overview
Integrated Services Digital Network (ISDN) is a switched digital technology that upgrades an ordinary analog telephone network to an all-digital, end-to-end network. Using ISDN, you can transmit all types of information, such as voice, data, and video. With ISDN, you no longer need to incur the expense of leasing an all-digital line to receive the high-speed benefits of digital technology.
The ISDN interface software allows you to interconnect routers over ISDN. You can set up the interface to act over a dedicated link or to initiate and accept switched-circuit connections, either on demand, automatically from restart, or on command by the operator.
BRI Interface
The ISDN interface is a Basic Rate Interface (BRI) with two 64 Kbps (kilobits per second) bearer (B) channels and one 16 Kbps data (D) channel. The interface uses the B channels for data transmission. It uses the D channel to set up calls.
The BRI interface establishes connections with a peer router over an ISDN connection. It accepts or initiates connections on command from dial circuits. Once the ISDN interface establishes a connection, it transparently passes data to and from the dial circuit.
Some switches in North America do not provide 64 Kbps service for ISDN data calls; instead, they offer only 56 Kbps service. In this case, the ISDN software automatically falls back to 56 Kbps.
Addressing
To place a call, you specify the name and directory numbers of the destination. To identify yourself to the destination, you specify your own directory number. For ISDN, directory numbers are called network dial addresses, and, for convenience, you give destinations names called network address names that represent the directory number.
You can add multiple numbers for each destination name. If you are using two ISDN directory numbers, you need to add both numbers for the same network address name.
If you define multiple numbers for a destination network dial address, the dial circuit attempts to call the first number. If the dial circuit is not able to complete the connection, it cycles through all of the defined numbers until it establishes the connection.
Cost Control Over Demand Circuits
Dial-on-demand circuits always appear to be in the Up state to routing protocols. Most protocols send out periodic routing information that can cause the router to dial out each time it sends routing information over dial-on-demand circuits. To limit periodic routing updates, configure IP to use only static routes and disable the routing protocol (RIP) over the dial circuits. Configure IPX for low-frequency updates or change updates so that the router sends broadcast messages at specified intervals, when there is data to send or if there is a problem. You should also enable IPX keepalive filtering, which prevents keepalive and serialization packets from continually activating a dial-on-demand link.
Caller ID
Some ISDN switch variants provide a feature called caller ID. Caller ID provides the telephone number of the calling router. The ISDN service uses this number to identify the name of the calling router.
DOSBS
Data Over Speech Bearer Service (DOSBS) is a method your router can use to place or receive 56K voice grade calls and then use the channels to pass data. Using DOSBS helps you to reduce your telephone bill because the cost for voice calls is generally lower than that for data calls. To use this ISDN feature, the ISDN line must be provisioned with voice on at least one B channel.
Notes:
Note: This is the default option when DOSBS is enabled.
Note: This is the default option when DOSBS is disabled.
POTS
Plain Old Telephone Service (POTS) is an extension of the ISDN functionality that is currently supported in your GTX 1000 router. It allows analog telephone equipment, such as telephones, FAX machines, and modems, to be directly connected to your OpenROUTE Networks GTX 1000 router. The telephone equipment contends for the available B-channels of the ISDN link along with traditional Point-to-Point Protocol (PPP) data links. With POTS on the GTX 1000, you can now use your ISDN connection for voice and data connections from a single platform.
Notes:
Figure 1 ISDN Point-to-Point Configuration

Figure 2 ISDN Multipoint Configuration

Frame Relay Over ISDN Configuration
Figure 3 shows how you can connect to a Frame Relay network through an ISDN network. In this configuration, you set the data link on your dial circuit to Frame Relay.
Figure 3 Frame Relay Over ISDN Configuration

ISDN With POTS
Figure 4 illustrates how to connect a GTX 1000 with an ISDN with POTS module to an ISDN.
Figure 4 ISDN with POTS

Switches Supported
The telephone company's switch variant, or type of switch, determines the capabilities of your ISDN service. It is your primary connection into the ISDN network. The switch variant determines how many ISDN devices you can handle, as well as what different configuration options you can have. Some switch variants support eight different devices, others support only two devices. The switch also determines which B channels support voice, video, data, or both. Most telephone companies provide a switch variant from one of switch variants in Table 1. OpenROUTE Networks routers support these switch variants.
Note: As of October 18, 1996, VN3 is obsolete in Europe.
ISDN Interface Restrictions
The following are some ISDN interface restrictions. You cannot
Config>list interfaces
Ifc 0, Ethernet/IEEE 802.3 (via device Ethernet)
Ifc 1, Point to Point (via device WAN1, with Dialer)
Ifc 2, Frame Relay (via device WAN2, with LAN Emulation)
Ifc 3, Point to Point (via device ISDN)
Ifc 4, Frame Relay (via device ISDN, with LAN Emulation)
Note: It does not matter which "via device ISDN" interface number you enter.
Config>network
What is the network number [0]? 3
Circuit Configuration
Circuit Config <NET-3>
Circuit Config <NET-3> bri
Basic Rate ISDN user configuration
BRI Config <ISDN>
BRI Config <ISDN> add addressTo see a list of your ISDN addresses, enter list address at the BRI Config <ISDN> prompt. To delete an ISDN address from your list, enter delete address at the BRI Config <ISDN> prompt. The software prompts you for the dial and subdial address to distinguish between the primary telephone number and the sub-addresses of different ISDN peripherals at that number.
Assign address name [1-23] chars? baltimore
Assign network dial address [1-25 digits]? 1-555-0983
Assign network subaddress [0-20 digits]? 23
BRI Config <ISDN> add addressTo delete all numbers for an address name that has multiple numbers, do not enter a network dial address when prompted.
Assign address name [1-23] chars []? baltimore
Assign network dial address [1-15 digits][]? 1-555-2657
Assign network subdial address [0-20 digits] []? 24BRI Config <ISDN> add address
Assign address name [1-23] chars []? baltimore
Assign network dial address [1-15 digits][]? 1-555-8797
Assign network subdial address [0-20 digits] []? 25
BRI Config <ISDN> del address
Delete address name [1-23] chars []? baltimore
Delete network dial address [1-15 digits][]?
Really delete all addresses under this name?(Yes or [No]):yes
Circuit Config <NET-3> bri
Basic Rate ISDN user configuration
BRI Config <ISDN>
BRI Config <ISDN>set switch-variant
Switch-Variant-Model []? usni1
BRI Config <ISDN>set multipoint-selectionIf you set the switch-variant to any type other than INS64, set the directory number of the local ISDN interface. Be sure that your address is unique.
Multipoint Selection [MP]? pp
BRI Config <ISDN>set dn0The colon (:) separates the address number from the sub-address.
Enter DN0 (Directory-Number-0) [ ]?1-555-0983BRI Config <ISDN>set dn0
Enter DN0 (Directory-Number-0) [ ]?1-555-0983:22
BRI Config <ISDN>set dn1You can assign a sub-address for dn1 in the same way as for dn0. (See step .)
Enter DN1 (Directory-Number-1) [ ]?1-555-2037
BRI Config <ISDN>set dn1
Enter DN1 (Directory-Number-1) [ ]?1-555-2037:28
BRI Config <ISDN>set spid
Which SPID [1]? 1
Enter Service Profile ID (SPID) []? 50855589530101
BRI Config <ISDN>set tei
Which TEI [0]? 0
TEI [AUTO]? 10BRI Config <ISDN>set tei
Which TEI [0]? 1
TEI [AUTO]? 12
BRI Config <ISDN>set framesize
Framesize in bytes (1024/2048/4096) [2048]? 2048
BRI Config <ISDN>enable dosbs
Figure 5 ISDN Point-to-Point Configuration

Config>network 3
Circuit Configuration
Circuit Config <NET-3> bri
Basic Rate ISDN user configuration
BRI Config <ISDN>
BRI Config <ISDN>add address
Assign address name [1-23] chars []? Remote1
Assign network dial address [1-15 digits][]? 555-2389
Assign network subdial address [0-20 digits] []?BRI Config <ISDN>add address
Assign address name [1-23] chars []? Remote2
Assign network dial address [1-15 digits][]? 555-7925
Assign network subdial address [0-20 digits] []?
BRI Config <ISDN>set switch-variant
Switch-Variant-Model []? usni-1
BRI Config <ISDN>set dn0
Enter DN0 (Directory-Number-0) [ ]?5559876BRI Config <ISDN>set dn1
Enter DN1 (Directory-Number-1) [ ]?5554961
BRI Config <ISDN>set multipoint-selection
Multipoint Selection [MP]? pp
BRI Config <ISDN>set spid
Which SPID [1]? 0
Enter Service Profile ID (SPID) []? 508555987600BRI Config <ISDN>set spid
Which SPID [1]? 1
Enter Service Profile ID (SPID) []? 508555496100
BRI Config <ISDN>set tei
Which TEI [1]? 0
TEI [AUTO]?BRI Config <ISDN>set tei
Which TEI [1]? 1
TEI [AUTO]?
BRI Config <ISDN>set framesize
Framesize in bytes (1024/2048/4096) [1024]? 2048
Figure 6 ISDN Multipoint Configuration

Config>network 3
Circuit Configuration
Circuit Config <NET-3> bri
Basic Rate ISDN user configuration
BRI Config <ISDN>
BRI Config <ISDN>add address
Assign address name [1-23] chars []? Remote1
Assign network dial address [1-15 digits][]? 555-2389
Assign network subdial address [0-20 digits] []?BRI Config <ISDN>add address
Assign address name [1-23] chars []? Remote2
Assign network dial address [1-15 digits][]? 555-7925
Assign network subdial address [0-20 digits] []?
BRI Config <ISDN>set switch-variant
Switch-Variant-Model []? usni1
BRI Config <ISDN>set dn0
Enter DN0 (Directory-Number-0) [ ]?5559876
BRI Config <ISDN>set multipoint-selection
Multipoint Selection [MP]? mp
BRI Config <ISDN>set spid
Which SPID [1]? 0
Enter Service Profile ID (SPID) []? 508555987600
BRI Config <ISDN>set tei
Which TEI [1]? 0
TEI [AUTO]?BRI Config <ISDN>set tei
Which TEI [1]? 1
TEI [AUTO]? none
BRI Config <ISDN>set framesize
Framesize in bytes (1024/2048/4096) [1024]? 2048
+network 3
Circuit <NET-3>
Circuit <NET-3> bri
Basic Rate ISDN user console
BRI <ISDN>
Not all parameters apply to all router platforms. Press Space twice after you type a command to display the available parameters for each command. Enter help for information about using the command line interface. [C] means the command is available at the BRI Config <ISDN> prompt. [M] means the command is available at the BRI <ISDN> prompt.
Accounting [M]
Displays the number of calls made, accepted, refused, and blocked for each destination.
Syntax: accounting
accounting
AccountingName Address Total: In Out Rfsd Outb_UpTime
gt70-43 98983500 0 0 0 0:00:00
gt70-44 98983600 0 0 0 0:00:00
----------------------------------------------------------------------
(unknown) - 0 - 0 -
Total Blocked Calls: 0
Add [C]
Adds accounting entries and addresses to the ISDN configuration.
Syntax: add
Example:
add accounting-entry
Assign accounting entry name []? newark
add address
Assign address name [1-23] chars []? newark
Assign network dial address [1-25 digits] []? 123456789
Assign network subaddress [0-20 digits] []? 1011121314
calls
RemoteSite Address Calls: In Out Rfsd ElapsedTime
(unknown) 0 0 0 -
(unknown) 0 0 0 -
Unmapped connection indications: 0
circuits
B-channel State BearerType Reason Duration
- Idle - Down -
- Idle - Down -
Conf_test_ cmds [M]
Invokes a submenu, where various commands can be issued to the router for conformance test purposes.
CAUTION:
These commands should never be used. Using these commands during normal router operation can cause erratic behavior of the ISDN interface, requiring the router to be reset. Delete [C]
Removes accounting entries and addresses from the ISDN configuration.
Syntax: delete
delete accounting-entry
Remove accounting entry name []? newark
Example:
delete address
Delete address name [1-23] chars []? newark
Delete network dial address [1-25 digits] []? 1-508-366-2345
Delete network subdial address [0-20 digits] []? 22
disable dosbs
enable dosbs
exit
list address
Address assigned name Network Address Network Subaddress
--------------------- --------------- ------------------
newark 123456789 1011121314
Example:
list parameters
Basic Rate ISDN Configuration
Switch Variant = NT DMS-100
Multipoint Selection = Point-to-Point
DN0 (Directory Number 0) = 5559873
DN1 (Directory Number 1) = 5552845
SPID0 (Service Profile ID 0) = 508555987300
SPID1 (Service Profile ID 1) = 508555284500
TEI0 = Automatic
TEI1 = Automatic
Maximum frame size (bytes) = 2048
Data Over Speech Bearer Service (DOSBS) = Disabled
POTS country profile = United Kingdom
No circuit address accounting information being kept.
The following output displays parameters with the country profile set to custom.
Example:
list parameters
Basic Rate ISDN Configuration
Switch Variant = NT DMS-100
Multipoint Selection = Point-to-Point
DN0 (Directory Number 0) = 5559873
DN1 (Directory Number 1) = 5552845
SPID0 (Service Profile ID 0) = 508555987300
SPID1 (Service Profile ID 1) = 508555284500
TEI0 = Automatic
TEI1 = Automatic
Maximum frame size (bytes) = 2048
Data Over Speech Bearer Service (DOSBS) = Disabled
POTS country profile = Custom
POTS line impedance = 600 ohm
POTS ringer frequency (Hz) = 25
POTS port 1 ringer cadence = United Kingdom
POTS port 2 ringer cadence = France
No circuit address accounting information being kept.
parameters
Basic Rate ISDN Port Parameters:
Switch Variant = US National ISDN-1
Multipoint Selection = Point-to-Point
DN0 (Directory Number 0) = 15551212
DN1 (Directory Number 1) =
SPID0 (Service Profile ID 0) =
SPID1 (Service Profile ID 1) = 56789
TEI0 = Automatic
TEI1 = Automatic
Maximum Frame Size = 2048
Data Over Speech Bearer Service (DOSBS) = Disabled
POTS country profile = United Kingdom
Basic Rate ISDN Port Parameters:
Switch Variant = US National ISDN-1
Multipoint Selection = Point-to-Point
DN0 (Directory Number 0) = 15551212
DN1 (Directory Number 1) =
SPID0 (Service Profile ID 0) =
SPID1 (Service Profile ID 1) = 56789
TEI0 = Automatic
TEI1 = Automatic
Maximum Frame Size = 2048
Data Over Speech Bearer Service (DOSBS) = Disabled
POTS country profile = Custom
POTS line impedance = 600 ohm
POTS ringer frequency (Hz) = 25
POTS port 1 ringer cadence = United Kingdom
POTS port 2 ringer cadence = France
No circuit address accounting information being kept.
Example:
set country
POTS country profile [NA]?Valid profiles are:
NA (North America)
UK (United Kingdom)
FRA (France)
GER (Germany)
EUR (Europe)
JAP (Japan)
CUST (Custom)
set country cust
POTS line impedance [TBR21]? 600
POTS ringer frequency in hertz [20]? 25
POTS port 1 ringer cadence pattern [NA]? uk
POTS port 2 ringer cadence pattern [NA]? fra
set dn0
Enter DN0 (Directory-Number-0) [ ]? 1-555-1234
ISDN Config>set dn0
Enter DN0 (Directory-Number-0) [ ]?1-555-1234:45
set dn1
Enter DN1 (Directory-Number-1) [ ]? 1-555-2345
ISDN Config>set dn1
Enter DN1 (Directory-Number-1) [ ]?1-555-2345:47
set framesize
Framesize in bytes (1024/2048/4096) [1024]? 2048
set multipoint-selection
Multipoint Selection [PP]?
set preferred
Preferred_Voice_Mode?SPEECH or 3_1KH
set spid
Which SPID [0]? 1
Enter Service Profile ID (SPID) []? 508555123400
Note: As of October 18, 1996, VN3 is obsolete in Europe. It has been succeeded by VN4.
set switch net3 tei auto or value or none
Sets the signalling TEI (terminal endpoint identifier) for the ISDN interface. This setting must match the signalling TEI of your switch. Check with your service provider for the correct TEI value.
Valid values are 0 through 63, Auto, or None. The default is Auto. The software lets you set a TEI for each B channel for switch variants that require this capability.
For ISDN lines that use a single TEI, setting the TEI to None disables the ISDN interface. For ISDN lines that use multiple TEIs, setting one of the TEIs to None prevents the interface from accessing one B channel.
5ESS, DMS100, and USNI1 switches require that you set the TEI for each B channel (TEI 0 or TEI 1). If you set the switch variant to one of those switches, entering set tei prompts you for which TEI to configure. In a multipoint configuration, you should set TEI 1 to None. Otherwise, the router could allocate both B channels and prevent other ISDN devices on the multipoint bus from accessing a B channel.
Example: set tei
Which TEI ? [0]? 1
TEI [NONE]?
statistics
Link: Inactive BRI Firmware: 0.0 Handler State: InstalledD Channel B1 Channel B2 Channel
Total Transmits 0 0 0
Total Receives 0 0 0
Transmit Bytes 0 0 0
Receive Bytes 0 0 0
Invalid Interrupts 0 0 0
Transmit: D B1 B2 Receive: D B1 B2
Error 0 0 0 Error 0 0 0
Overflow 0 0 0 Overflow 0 0 0
Underrun 0 0 0 Overrun 0 0 0
Abort 0 0 0 Abort 0 0 0
CRC Error 0 0 0