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Preprogrammed Instructions

Instruction Lists

To reduce interactive messaging, you can preprogram instructions for a channel at the Signaling layer for faster call processing and simpler host applications. To preprogram instructions for a channel, use the Inseize Instruction List Configure and Outseize Instruction List Configure messages.

Important! The ISDN, SS7, and IP calls do not support the following messages: Inseize Instruction List Configure, Outseize Instruction List Configure, and Inseize Control.

The host sends inseize and outseize instructions to the CSP using Inseize Control and Outseize Control messages. The instructions reside within these messages in blocks of data named Information Control Blocks (ICBs). You can insert multiple ICBs into these messages.

Customizing Preprogrammed Instructions

You can customize the default instruction lists for individual channels with the Inseize Instruction List Configure and Outseize Instruction List Configure messages. Your customized list can have up to 20 instructions. (The explanation of these messages in the API Reference contain examples to help you configure your own lists.)

Initiating Preprogrammed Instructions

To initiate a preprogrammed instruction list for a channel, you can send a Use Instruction List ICB in the Inseize Control, Route Control, or Outseize Control messages.

The Use Instruction List ICB allows the host to begin at any instruction number in the list. The Signaling layer begins executing at the specified instruction number and continues until it encounters a "Wait For Host Control" instruction.

This arrangement allows the host to program a channel’s instruction list in sections. The host can use different sections of the list for different scenarios, depending on the processing needs of a specific call.

Process

When an inseizure is detected, the Signaling layer executes the channel’s instruction list. The host initiates outseize instructions by issuing a Route Control or Outseize Control message with an instruction of "Use Instruction List."

Important! To initiate outseizures, use an instruction of Seize. You cannot include a seize instruction in a preprogrammed list.

Using preprogrammed instructions, the host determines the following:

• What information it receives from the CSP.

• When it receives information from the CSP.

• At what point during call setup it begins interactive processing.

In a preprogrammed list, the last instruction should be "Wait For Host Control" or "Wait For Host Control With Answer Supervision" (outseize only). The CSP then waits for more instructions from the host before it proceeds with call setup. The host can then manage the call interactively, or initiate the instruction list again at a different instruction number.

Outgoing call setup during real-time call processing on a specific channel.
See Integrated Services Digital Network.
See Signaling System Number Seven.
Internet Protocol. Part of the TCP/IP family of protocols used to route messages and tracks the addresses of nodes.
Incoming call setup during real time call processing on a specific channel.
ICB. A standardized block that allows control data to be inserted in a standard way into API messages.
See Information Control Block.
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.