Nortel DMS-100 Series Maintenance Manual page 126

3-10 SMS signaling
Custom local area signaling services (CLASS) features The
following CLASS features are supported:
Ringing The following ringing types are supported:
The SMS supports ringing on subscriber lines attached to an RCS. The SMS
sends different A- and B-bit signaling patterns over DS-1 lines to a
connected RCS. This action causes the RCS to ring subscriber telephone
sets.
The DMS-100 switch uses specific signaling patterns for coin, special
service, and single-part lines and multiparty lines. These signaling patterns
are described in the Bell Communications Research document, Digital
Interface Between the SLC96 Digital Loop Carrier System and a Local
Digital Switch (TR-TSY-000008).
The SMS-RCS subsystem supports all currently available types of ringing.
The types of ringing include coded, FSR, and superimposed. A single RCS
uses one type of ringing at a time.
Frequency selective ringing The SMS-RCS subsystem supports FSR
for single-party, two-party, four-party and Meridian Digital Centrex (MDC)
lines. There are two types of FSR channel units or cards. These cards are
referred to as FSR cards in this document. The following are the FSR cards
in the SMS-RCS subsystem:
297-8231-550 Standard 09.01 August 1998
calling number delivery (CND)
automatic call back (ACB)
automatic recall (AR)
customer originated trace (COT)
calling number delivery blocking (CNDB)
bridged ringing
— single-party
superimposed ringing
— multiparty
– four-party fully selective
– eight-party semiselective
coded
frequency selective ringing (FSR)
Ω
SCD222 for 900- loops