Functional Limits - Nortel DMS-100 Series Maintenance Manual

2-28 Functional overview
Signaling and supervision
Signaling allows the DMS-100 switch to communicate with DMS-100 switch
stations or other switching offices. The OPM uses DMS-X protocol to
communicate over the DS-1 links with the host office. The DMS-X is a
half-duplex, byte-oriented protocol like the DS30. The DMS-X is responsible
for the transmission and reception of message data over full-duplex media like
the DS-1 links. The DMS-X is a state-driven code. The DMS-X requires
handshake-messaging between the OPM and host at each stage of data
transfer.
The byte transfer rate over DS-1 channels is 125 bytes per microsecond.
Subscriber tones
The host LTC/LGC provides correctly cadenced tones that the OPM applies as
needed to subscriber lines. The tones that the host LTC/LGC supports and the
OPM applies follow:
•
•
•
•
•
•
The OPM depends on the DMS-100 switch CC and is not involved in any
signaling between the host office and other systems.
Intraswitching capability
Feature package NTX156AA provides intraswitching capability to the OPM.
The intraswitching feature distributes the traffic load in the OPM again. This
event occurs so that the DS-1 links to the host are available to handle external
calls. The intraswitching feature allows calls between subscribers served by
the same LCM unit of the OPM to be connected. The name of this condition
is intraswitching. When calls between subscribers on different LCM units of
the OPM must connect, the name of the condition is interswitching. The LCCs
in the HIE shelf are responsible for intraswitched and interswitched calls. The
LCCs in the HIE shelf connect serially to the DS30A ports of the LCM.
For more information on intraswitching, refer to the data schema section of the
Extended Peripheral Module Translations Reference Manual.

Functional limits

For feature package NTX146AA to work correctly, certain conditions must be
observed. These limits can be hardware-dependent or software-dependent, as
follows.
297-8361-550 Standard 04.02 December 2004
dial tone
audible ringing
warble (MDC Meridian business set ringing)
busy tone
reorder tone
receiver off-hook (ROH) tone