# General

Here you will find the overarching settings for exchange connections.

Table 1. Automatic exchange line request
Parameter | Explanation
Apply exchange prefix if dialling number has equal or more digits | Exchange prefix is added if the dialed number is equal to or more than the number specified in this field. Default number is 9.
Digit dial timeout (s) | Default is 4 seconds
Auto completion of exchange prefix for CTI applications | Enables auto completion of exchange code. This feature is available for MiCollab, BluStar, Mitel One and Dialer applications.

Table 2. Trunk-to-trunk mode
Parameter | Explanation
Exchange-to-exchange connection | This setting lets you restrict or bar exchange-to-exchange traffic throughout the system: Not enabled: No exchange-to-exchange connections can be set up. Digital-digital only: For an exchange-to-exchange connection to be set up, both network interfaces must be digital. Digital-analogue also: For an exchange-to-exchange connection to be set up, at least one network interface must be digital. Analogue-analogue also: An exchange-to-exchange connection is always possible.
Disconnect timeout (min) | Only for call type Also analogue-analogue: The connection is cleared down after the set disconnect timeout.
Wait for connection | Lets you specify whether a configured Call Forwarding Unconditional to the exchange in the case of an external call is always switched through or only if the caller takes the call and sets up a connection as a result: The call forwarding unconditional is switched through only if a connection is set up. If the destination user is busy or unobtainable, this setting ensures that the caller does not incur charges for the connection up to the communication server. The call forwarding unconditional is always switched through.

## Clock reference and clock reference table

The clock frequency of a communication server is provided (synchronized) by the public network via the basic accesses BRI-T and the primary rate accesses PRI. Should synchronization by the public network fail (due for example to exchange line interruptions), the communication server will use its own clock. The default settings made automatically are sufficient in almost all cases. Only change the settings if you have a special configuration that requires a change (e.g. for private networking or for CAS/R2).

Table 3. Recall / ringing duration
Parameter | Explanation
Used reference | This is the port currently being used for synchronization.
Master reference | This port is the Master reference.
Synch state | Current synchronization status.

Parent topic: Exchange
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