Administrator's Guide

DS1 trunk service
Issue 5 October 2002 1659555-233-506
Considerations
■ If Distinctive Ringing is disabled, the system generates a 1-burst repetitive
tone for all incoming calls. This is useful for equipment interfaced by
analog lines, especially if you use off-premises station.
■ A single distinctive ring cycle is used for each new incoming call to an
off-hook telephone or headset. The system alerts a CALLMASTER
terminal with a single ring cycle whenever either the headset or the handset
is plugged into the headset jack.
Interactions
■ Personalized Ringing
The called party hears the user-selected ringing pattern for the distinctive
ring cycles.
DS1 trunk service
Digital Signal Level 1 (DS1) trunk service uses bit-oriented signaling (BOS) and
multiplexes 24 channels (T1 service) or 32 channels (E1 service) into a single data
stream. DS1 can be used for voice or voice-grade data and for data-transmission
protocols. T1 trunk service multiplexes 24 channels into a single 1.544-Mbps data
stream. E1 trunk service multiplexes 32 channels into a single 2.048-Mbps
stream. Both T1 and E1 provide a digital interface for trunk groups.
For information about how to administer DS1 with enhanced administration, see
‘‘Signaling modes’’ on page 1662.
Brief description
DS1 trunk service provides a digital interface for the following trunks.
■ Voice-grade DS1 tie trunks
■ Alternate voice/data (AVD) DS1 tie trunks
■ Robbed-bit AVD (RBAVD) DS1 tie trunks
■ Digital Multiplexed Interface (DMI) tie trunks
■ Integrated Services Digital Network-Primary Rate Interface (ISDN-PRI)
trunks
■ Central Office (CO) trunks
■ Foreign Exchange (FX) trunks
■ Remote-access trunks