TANDBERG D50104-15 user manual Below is a list of common ISDN-PRI/T1 switches, Channel Hunting

			Health Care System III	Advanced Use
Below is a list of common ISDN-PRI/T1 switches.
	Type	Manufacturer	PRI Switch Type setting
	ATT 4 ESS	AT&T	AT&T ISDN
	ATT 5 ESS	AT&T/Lucent	AT&T ISDN or National ISDN*
	DMS 100	Northern Telecom	National ISDN
	DMS 250	Northern Telecom	National ISDN
	* Settings will depend on configuration of the switch. PRI Switch Type is not changed when Restoring Defaults.

Channel Hunting

Max Channels	Maximum number of channels the unit may use at any given time.
Low Channel	The lowest numbered B-channel that may be used by the unit when selecting channels
	for outgoing calls.
High Channel	The highest numbered B-channel that may be used by the unit when selecting channels
	for outgoing calls.
Search	Specifies where the system will start searching for available B-channels for outgoing calls.

PRI line

Codec 1

Low Channel: 10

High Channel: 20

Max Channel: 6

PRI 1

PRI 2

Channel hunting is normally used in conjunction with PRI daisy-chaining with TANDBERG units in the daisy-chain. If only TANDBERG units are used in the daisy-chain, default setting should be used, as these units will find available B-channels automatically.

Max Channels may be used for PRIs that are provisioned for a lower number of channels.

Codec 2 or

PBX

Channels: 1-9

will be available for the codec/PBX

Max Channels may be used as mechanism to ensure that there is bandwidth available to codecs further down the chain when Daisy-Chaining.

‘High Channel’, ‘Low Channel’ and ‘Search’ may be used for PRIs provisioned with specific requirements for B-channel usage.

In this example, the unit will start searching for available B-channels at channel 20, because ‘Search’ is set to ‘High’ and ‘High Channel’ is set to 20. The unit will not search for channels below 10, because ‘Low Channel’ is set to 10. Furthermore if the user tries to make an 8 channel call, the call will be established with 6 channel, because ‘Max Channels’ is set to 6.

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