Perle 833IS, User Manual

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Chapter 6: Configuring the Interfaces
Perle 833IS User Guide 81
An S/T line can be ordered (or configured, if on a PBX) such that clocking is not
supplied unless a call is active on the S/T line. It is strongly recommended that at
least one S/T BRI line always provide line clock.
The 833IS will synchronize to the lowest number BRI line that provides clocking.
When clocking is lost, it will switch to an internal clock while it looks for another
BRI line providing clocking. Although this process is quick, calls on other BRI lines
that are active while this clock is resynchronizing could experience data errors.
A BRI line will be assigned a phone number per B channel. However, it is not safe
to assume that the phone number is tied to the channel. When a call comes in, it
signals on the D channel what B channel the call is on, and what phone number is
used. Thus it is possible to get a call on the first B channel from the second phone
number.
ISDN BRI U
Interface
Configuration The ISDN BRI U interface configuration screen is as follows:
Network Protocol
Specifies the network protocol used by the carrier. These network protocols are
supported: