Supervisory Port
An RS232 communications port located on the Access-T rear panel.
The Supervisory Port is intended for use with a far-end device and is
the only Access-T port equipped for modem connection.
T1
T1 refers to a digital bipolar link with a data capacity of 1.544 Mbps,
also known as Digital Signal Level 1 (DS1). The T1 digital transmis-
sion system is the primary digital communication system in North
America.
TABS (Telemetry Asynchronous Block Serial)
An AT&T-defined request-and-response protocol used for commu-
nication between monitoring/terminating equipment and a com-
puter-based Network Management System (NMS).
Telco Register
The telco registers record performance of the input from the T1 line.
Telco registers can be accessed from the network as well as from the
supervisory interfaces, but can be cleared only from the network or
by restarting the NIM.
Terminal Interface
The Terminal Interface provides drop-down menus, plus commands
to display performance reports and perform other functions, using a
standard ASCII terminal.
Unavailable Second (UAS)
A second during which Unavailable Signal State is in effect. The
initial ten SES are counted as UAS, requiring an adjustment of the
SES count. The ten non-SES resulting in the clearing of Unavailable
Signal State are not counted as UAS. (See Figure B-1.)
Unavailable Signal State
USS is declared at the first of 10 consecutive seconds of SES; it is
cleared at the first of 10 consecutive seconds which are not SES.
Unsolicited Alarm Reports
Alarm information sent automatically to an NMS (in modified TABS
format) when user-selected alarm conditions occur.
ACST-0351-005
Appendix B
June 1996
Glossary
B-9
