Telos Zephyr Xstream - Manual (Page 370)

USER’S MANUAL
Appendix 10 – Glossary 358
Primary Rate Interface A form of ISDN with 23 “B Channels” and one “D channel”. All 24
channels are on a single cable. Functionally related to T1 telephone circuits. In Europe PRI has 30
“B Channels” and one “D Channel” and one “Sync channel”. See also B channel and D channel.
Provisioning The act of configuring an ISDN or other telecommunications path. Also refers to
the complete line configuration information.
PS2 Power Power provided on pins 7 and 8 of the “S” interface cable. This power is used so
that a NT1 can provide power to a terminal (usually a phone). In some cases, it is used to allow a
terminal to power an NT1. The USA versions of the Zephyr, ZephyrExpress, supply PS2 power in
the “S” jack. The Zephyr Xstream and Telos TWO provide this on all versions. This power
arrangement is also used in the Telos TWOx12 and 2101 Studio Interface to power Desktop
Directors.
PTP (USA) AT&T “Custom Point to Point” Custom ISDN Protocol. Point‐ to‐ Point lines have only
one incoming phone number which must be dialed twice to connect to both lines (the first call
goes to “line 1” and the second call rolls over to “Line 2”. See Custom ISDN and ISDN Protocol.
QoS (Quality of Service) is the ability to provide different priority to different applications,
users, or data flows, or to guarantee a certain level of performance to a data flow. For example,
a required bit rate, delay, jitter, packet dropping probability and/or bit error rate may be
guaranteed. Quality of service guarantees are important if the network capacity is shared,
especially for real‐time streaming multimedia applications such as Livewire
TM .
RBOC‐ Regional Bell Operating Company (USA) One of the regional companies formed when
AT&T was forced out of the local telephone business. Each RBOC (or “baby bell”) owns a number
of the former “Bell Operating Companies”. The Bell Operating Companies are the traditional
local phone companies (pre‐ 1984), except where one’s service is from an “Independent” (non
bell) telephone company or a CLEC. Due to their former association with the Bell System RBOCs
are regulated by the FCC differently than are independent Telcos or CLECs. In many cases the
Bell Operating Company structure is no longer used. For instance, here in Ohio we now deal
directly with the RBOC, Ameritech, while the old Bell Operating Company, Ohio Bell Telephone,
no longer exists. Another trend is mergers among the RBOCs (and in some cases the
independents as well). See CLEC and LEC.
RD‐ Receive Data Data coming from the network, or DCE towards the DTE. Also, a light on a
modem or CSU/DSU that lights to indicate presence of this signal.
Red Alarm An alarm state on a T‐ carrier circuit that indicates that the incoming signal (at the
network interface) has lost frame for more than a few seconds. Normally a Yellow alarm is then
returned (i.e. sent back) if a Red alarm is present. A Red Alarm indicates a loss of inbound signal;
a Yellow alarm indicates (indirectly) a loss of outbound signal. See also Yellow alarm, Blue alarm,
and LOS.
Regional Bell Operating Company See RBOC
Repeater A device intended to extend ISDN telephone service to sites further from the central
office than could normally be served. i.e.: beyond 18,000 feet. ISDN repeater technologies
include “BRITE”, “Virtual ISDN”, “Lightspan”, and “Total Reach”. Some Telcos do not use
repeaters. Compatibility between a given NT1 (CPE) and a repeater is less certain than if that
CPE where directly connected to the switch.