ELSA MicroLink ISDN/PCC-16 User Manual page 49

CAPI
CCITT
Control channel
D channel
Data channel
DSS1
EAZ
Effective transfer
rate
ETSI
Euro-ISDN
Firmware
FOSSIL
MicroLink ISDN/PCC-16 Manual © 1997 ELSA GmbH
Common ISDN Application Programming Interface . This software interface
was originally developed by German ISDN adapter manufacturers in
cooperation with the German FTZ, and is used for communication between
ISDN adapters and ISDN application software. ELSA drivers support CAPI
version 1.1 or 2.0, allowing the use of standard ISDN software for fax group 3
and 4, data communications and file transfer. CAPI 2.0 is an internationally
accepted standard for ISDN software interfaces.
→ → ITU-T
ISDN signaling channel (also called D channel ,
of control data (e.g. message about incoming call etc.) between the ISDN
interface and the public exchange at a transfer rate of 16,000 bps for
Rate Interfaces, or 64,000 bps for
Control channel
→ →
ISDN transmission channel (also called B channel ) for the transmission of data
with a transmission rate of 64,000 bps.
A European standard developed by the
(also called Euro-ISDN ). In Germany, this standard was introduced in 1993
and is likely to replace the older national 1TR6 protocol. For an intermediate
period, ISDN interfaces in Germany will support both protocols.
The Endgeräteauswahlziffer (German for Terminal Device Selection Digit ) is
used by the → → 1TR6 protocol to distinguish between several terminal devices
connected to the same ISDN Basic Rate Interface. Unlike the
→ → DSS1 protocol, this digit is appended to the ISDN number as the last digit.
The effective transfer rate must be distinguished from the transmission rate.
The transmission rate indicates the number of bits per second physically
transmitted over a data line as a theoretical maximum value, whereas the
transfer rate is a measure of the average amount of usable data transmitted
per unit of time. Control data and protocol headers, which are to be sent in
addition, can reduce the effective speed of transmission. On the other hand,
using data compression methods can result in an increase of the effective
transfer rate to a multiple of the physical transmission bit rate.
European Telecommunications Standards Institute.
committee has developed a European standard for the
→ → DSS1).
→ → DSS1
Firmware refers to the control software integrated into the device hardware,
and which cannot be modified by the user.
Fido/Opus/SEAdog Standard Interface Layer was developed for the use of
hardware-independent interfaces in data communications and is supported by
→ → DSS1) for the transmission
→ → Primary Rate Interfaces.
→ → ETSI for the
→ →
Appendix: Glossary
→ → Basic
→ → D channel protocol
→ → MSN in the
This standardization
D channel protocol (
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