Appendix: Glossary
50
MicroLink ISDN/PCC-16
Manual © 1997 ELSA GmbH
many standard communications programs (e.g. Telix, Telemate, Frontdoor or
Binkly).
Host
Host
designates a central computer that carries out certain functions for other
units (e.g. terminals), such as file handling etc.
ISDN
Abbreviation of
I
ntegrated
S
ervices
D
igital
N
etwork.
ISDN a/b adapter
ISDN a/b adapters are used to connect non-ISDN devices to the ISDN. An
ISDN a/b adapter, for example, connects devices designed for analog
telephone networks, such as analog telephones, class 2 and 3 fax devices,
modems etc. to the ISDN.
ITU-T
The
T
elecommunications Standardization Sector
of the
I
nternational
T
elecom-
munications
U
nion
(ITU) is working on the standardization of data and
telephone services. The ITU-T standards of the V. series mainly deal with
data transmission across telephone networks, while the I. and Q. series are
standards for the ISDN. The ITU-T is the successor organization of the CCITT
(
C
omité
C
onsultatif
I
nternational
T
élégraphique et
T
éléphonique).
MSN
M
ultiple
S
ubscriber
N
umber.
The
→
→
DSS1 protocol allows several access
numbers to be assigned by the exchange operator to a single ISDN line.
Normally these are three numbers, but may be up to eight. Similar to the
→
→
EAZ digits of the
→
→
1TR6 protocol, these numbers can be used to select one of
several terminal devices connected to the same
→
→
S
0
bus. Unlike the EAZ
digit, which is appended to the access number, an MSN is a unique and
proper access number up to eight digits long.
Multiple Subscriber
→
MSN
Number
NT
N
etwork
T
erminator.
This is a device installed on the terminal side of an
ISDN
→
→
Basic Rate Interface which converts the signals coming from the
exchange into the form needed by the
→
→
S
0
interface, and vice versa.
Primary Rate
ISDN interface providing 30
→
→
data channels (64,000 bps each) and one
Interface
→
→
control channel (64,000 bps). At the time of press, this ISDN connector is
only used for large private branch exchanges.
S
0
interface
Also called
S/T interface
. Serial bus interface between the Network
Terminator (
→
→
NT) of a
→
→
Basic Rate Interface and the ISDN terminal devices.
Up to eight terminal devices can be operated simultaneously on one S
0
bus,
and up to 12 connection sockets can be connected to the bus.
Semi-permanent
A leased-line connection on demand. This service is provided for the German
connection
→
→
1TR6 protocol only and can be ordered for any pair of ISDN stations and
separately for each B channel. Semi-permanent connections are leased for a
monthly flat rate independent of the length of the actual calls and can give
significant cost savings in the case of frequent or long calls.
S/T interface
Another name for the
→
→
S
0
interface, used for example in the USA.
