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Configuring ISDN PRI

Purpose

This section describes the procedures for configuring primary rate ISDN and National ISDN PRI NI 2. The first four steps of the basic ISDN configuration are described in more detail in other parts of this chapter:

• Span Configuration

• D Channel Configuration

• B Channel Configuration

• Optional Configuration

More details about bringing spans and channels in service, reconfiguration, and querying information are provided following the configuration sequences in this section.

Before you begin

The basic ISDN configuration assumes a 23+D (Primary Rate Interface) in North America and 30B+D outside of North America.

ISDN PRI Configuration Sequence

The table below shows the basic ISDN configuration sequence.

Step | Action | Description | API Message
--- | --- | --- | ---
1 | De-Configure Spans | If the spans were previously configured for a different protocol, de-assign the Logical Span ID of the ISDN card by setting the slot and spans (logical and physical) to 0xFF. | Assign Logical Span ID (0x00A8) message
2 | Configure Spans | - Assign Logical Span IDs - Configure span formats | Assign Logical Span ID T1 Span Configure E1 Span Configure
3 | Configure the D channels | - Assign D channels - Configure D channels - Add NFAS Facilities | D Channel Assign ISDN Interface Configure D Channel Facility List Configure
4 | Configure the B channel | Configure B channel options | B Channel Configure
5 | Optional Configuration | - PPL Customization - Features |
6 | Bring spans and channels in service | Bring spans, D channels, and B Channels in service | Service State Configure

National ISDN User Side Configuration

The following table provides a sample procedure for configuring the User Side endpoint variant of National ISDN PRI NI 2:

Step | Action
--- | ---
1 | De-assign the Logical Span ID of the ISDN card by setting the slot and spans (logical and physical) to 0xFF. Use the Assign Logical Span ID (0xA8) message.
2 | Assign logical span IDs to spans and channels. Use the Assign Logical Span ID (0xA8) message.
3 | Configure the T1 Span. Use the T1 Span Configure (0xA9) message.
4 | Assign a channel as an ISDN PRI D channel. Use the D Channel Assign (0xC4) message.
5 | Define the connection type for National ISDN PRI NI 2 user side as 0x09. Use the ISDN Interface Configure (0x60) message.
6 | Define the spans that are controlled by a D channel (including any spans in NFAS mode). Use the D Channel Facility List Configure (0xC6) message. For the Action field, select 0x01 (Add Facility) For Facility Number, select 0x01-0x1E, depending on the number of spans being added.
7 | Define the network type for the B channels. Use the B Channel Configure (0xC8) message. For the Network Type (0x01) field, select 0x01 (Do Not Include Network-Specific Facilities IE)
8 | Bring spans, B channels and D channels in-service. Use the Service State Configure (0x0A) message with appropriate AIBs. Send the message for each configuration.

Bringing Spans and Channels In Service

When all of the configuration is complete, bring up the D channel to establish a connection with the network and then begin call processing.

After establishing a connection to the network, the CSP sends the DS0 Status Change message to the host with the status of in-service. The DS0 Status Change messages follow for the B channels (voice/data channels).

If there is a link failure, the CSP sends the DS0 Status Change message to the host for the D channel, as well as all of the associated
B channels. All channels have a status of out-of-service.

Reconfiguration

Before performing reconfiguration, the CSP must be in a known state regardless of system events such as the removal or reset of cards or a host restart. Depending upon the event, the CSP determines which steps to take to get the interface operational.

The simplest approach is to send a Reset Configuration message indicating 0xFF for the Matrix Controller slot number. The configuration of all cards resets. The application must wait for the Card Status Report messages to be sent to the host before configuration begins. Sending this message clears all host-configured options, including downloaded PPL tables.

Another approach is to use Reset Configuration for the ISDN slot number, which defaults configuration for all D channels assigned to the card. Use this approach for an application that reconfigures certain features in the CSP during a live installation.

To remove a single D channel’s assignment and configuration, send the Assign Logical Span ID message (indicating de-assignment) for the D channel span.

Querying Information

Use the ISDN Query message to get parameters configurable with the ISDN Terminal Configure and ISDN Interface Configure messages, as well as assigned protocols.

Example

The following is an example of the ISDN Query message to query the General Interface Options and the response from the CSP.

API Message

Trace H->X FE 00 0E 00 63 00 00 01 00 01 0D 03 00 01 17 01 00

Byte | Field Description | Value and Indication
--- | --- | ---
0 | Frame | 0xFE
1, 2 | Length | 0x000E
3, 4 | Message Type | 0x0063
5 | Reserved | 0x00
6 | Sequence Number | 0x00
7 | Logical Node ID | 0x01
8 | AIB Address Method | 0x00 (Single Entity)
9 | Number of Address Elements | 0x01
10 | Address Element Type | 0x0D (Channel)
11 | Data Length | 0x03
12, 13 | Data[0,1] Logical Span ID | 0x0001
14 | Data[2] Channel | 0x17 (Channel 23)
15 | Query Type | 0x01 (General Interface Options)
16 | Query Subtype | 0x00 (None)
170 | Checksum | 0xCS (not shown in trace)

API Response

Trace X->H FE 00 1B 00 63 00 00 01 00 10 00 01 00 00 00 01 00 00 00 01 00 01 00 01 00 01 00 03 00 00

Byte | Field Description | Value and Indication
--- | --- | ---
0 | Frame | 0xFE
1, 2 | Length | 0x001B
3, 4 | Message Type | 0x0063
5 | Reserved | 0x00
6 | Sequence Number | 0x00
7 | Logical Node ID | 0x01
10, 11 | Data[0,1] Connection Type | 0x0001 (Lucent 4ESS)
12, 13 | Data[2,3] Options | 0x0000 (No options)
14, 15 | Data[4,5] D Channel Physical Medium | 0x0001 (64 Kbps)
16, 17 | Data[6,7] HDLC Bit Polarity | 0x0000 (Normal)
18, 19 | Data[8,9] Network Side Layer 2 | 0x0001 (Network Side (C/R Bit Inverted))
20, 21 | Data[10,11] B Channel Selection Mode | 0x0001 (Linear Clockwise)
22, 23 | Data[12,13] Location | 0x0001 (Private Network/Local User)
24, 25 | Data[14,15] Channel Release Request on ISDN Disconnect | 0x0001 (Send Host Channel Release Request on ISDN Disconnect)
26 | Data[16,17] Protocol Discriminator Value for Maintenance Messages | 0x0003 (Default)
28 | Data[18,19] B Channel Encoding for Transmission | 0x0000 (Channel Number)
30 | Checksum | 0xCS (not shown in trace)

See Integrated Services Digital Network.
Range of channels provided by T1 or E1 transmission service. A physical span is a group of channels taking up a single physical wire. A logical span is a group of channels taking up less than a single logical wire, or carried over more than one physical wire.
Data channel. One of two fundamental components of an ISDN interface, it provides a path (16Kbps for BRI, 64Kbps for PRI) for carrying control signals and call data in a packet-switched mode.
Bearer channel, 64Kbps (ISDN) The channel that carries the actual payload (as opposed to D-channels, which carry signaling data that helps route the payload).
PRI. One of two basic ISDN interface configurations providing 23 (30 outside of North America) Bearer channels (64 Kbps data) and 1 Data signaling channel (16 Kbps control and signaling data). Commonly refered to as ISDN PRI or 23B+D interface (30B+D outside of North America).
Digital communications link - voice, data, and video at a 1.544 Mbps rate (24 64 Kbps channels)
A digital communications link - voice, data, and video at a 2.048 Mbps rate; 30B/2D or 31B/1D (ISDN); non-North American version of T1.
See Non Facility Associated Signaling.
See Programmable Protocol Language.
The condition of a component at a given instant. The current "context" of a PPL object, such as Idle, Seizing, Answered. In PPL files, a State is represented by a circle.
In PPL, a condition that, when met, drives a state machine (PPL Component) from one state to another, by invoking an associated Primitive. In PPL files, an Event is marked by an arrow and text.
A group of data bits in a specific format, with a flag at each end to indicate the beginning and the end of the frame.
See Address Information Block.
The information in an AIB that follows the header, down to the data field. An AIB can have one or more Address Elements. AEs correspond to Span, Channel, and SS7 Link.
A computer, attached to the Excel platform through an RS-232 or Ethernet link, from which you run the telecommunications application that controls the Excel platform.