# Trunk Circuit Descriptor - Digital DID

## Purpose

The Digital DID Trunk Circuit Descriptor form is used to assign signaling and timing parameters to groups of DS1 DID trunk circuits using channel associated signaling (CAS).

Use this form when performing the following tasks:

- Direct Inward Dialing

- Program T1/D4 Trunks

- Program Embedded T1/D4 Trunks

NOTE: The operating characteristics for all trunks are defined by the respective trunk circuit descriptor form. There are 32 trunk circuit descriptor numbers available. These must be shared between all trunks in the system. As well, each circuit descriptor number assigned must be unique. MITEL recommends that the circuit descriptor numbers be allocated to each type of trunk in blocks. For example, CO trunks may be allocated circuit descriptor numbered 1 through 4, E&M trunks numbered 5 through 12, DS1 DID trunks numbered 13 through 21, and so on.

## Field Descriptions

Parameter | Description | Default Value
Number | Enter a number from 1 to 32 to uniquely identify each entry. | Blank
Ignore Far End Disconnect | Select "Yes" or "No" to indicate whether the trunks are to ignore or respond to a far-end disconnect signal. | No
Release Acknowledge Timer | Enter the amount of time the system will wait for a release acknowledgement from the far-end. Allowed values are 40 - 9000 units (200 ms - 450 sec), each unit being equal to 50 ms. | (80 UNITS) 4s
Address Signalling | Select the appropriate value to indicate the type of signaling used. NOTE: When systems are connected via T1/D4, the address signaling must match on either end of the connection. If one end is programmed as Loop and the other as DTMF, the dialed digits will not be translated by the receiving system, and the call will fail. | DTMF
Incoming Start Type | Select the appropriate value to indicate whether the trunk is immediate, delay dial, or wink start on incoming calls. Applies only to DS1 DID trunks. | Wink
Far End Connection | Not applicable to this release. | Local Office
Flash Timer | Enter a value between "200" and "700" milliseconds in increments of 50 milliseconds. This timer specifies the duration of the single trunk flash or each of the flashes for a double trunk flash. For a double flash, the time between flashes is hard-coded at one second. | 300 ms