Insys ISDN Terminal Adapter 4.0 11-02-01-02-00.015 用户手册
产品代码
11-02-01-02-00.015
ISDN Information
45
Version 2.02 – 01.04
9.2.2 B Channel
Each basic rate interface (multipoint and ISPBX connection) has 2 B channels available.
The information transmission in the B channel takes place unsecured in ISDN. Security
procedures have to be used for flawless transmission therefore.
X.25
The information transmission in the B channel takes place unsecured in ISDN. Security
procedures have to be used for flawless transmission therefore.
X.25
X.25 is a protocol for data transmission in packet switched networks like Datex-P of the
German Telekom.
X.31
German Telekom.
X.31
X.31 is an international manufacturer-independent ITU standard for the connection of
ISDN systems to X.25 networks. Packet oriented terminal devices are supported by ISDN
using X.31.
X.75 Protocol
ISDN systems to X.25 networks. Packet oriented terminal devices are supported by ISDN
using X.31.
X.75 Protocol
The X.75 protocol is also known as X.75SLP (=Single Line Protocol). X.75 is the standard
protocol for data transmission in packet switched networks in ISDN with a transmission
rate of 64 kbit/s.
It has the same use like V.42 for modem connections in principle. It extends the payload
data from higher layers to obtain information about failure control. The X-75 layer of the
remote party checks all data using this information and requests the data again if it de-
tects that they have been falsified during transmission.
There are three more parameters which can be set for the X.75 protocol.
• The data block size on layer 2 (data length, frame size, block size)
protocol for data transmission in packet switched networks in ISDN with a transmission
rate of 64 kbit/s.
It has the same use like V.42 for modem connections in principle. It extends the payload
data from higher layers to obtain information about failure control. The X-75 layer of the
remote party checks all data using this information and requests the data again if it de-
tects that they have been falsified during transmission.
There are three more parameters which can be set for the X.75 protocol.
• The data block size on layer 2 (data length, frame size, block size)
• The maximum number of blocks to be sent (window size)
• The module mode
HDLC transparent (layer 1b protocol)
• The module mode
HDLC transparent (layer 1b protocol)
The HDLC protocol is a control protocol for the data transmission for point-to-point or
point-to-multipoint connections and is usually used (automatically) in connections with
X.75 for data protection.
HDLC uses no control characters and is code-independent. To transmit data within HDLC,
the connection will be established first, then the data transmission takes place, and then
the connection will be terminated again. Failures are detected by using so called frames
and windows during transmission and the transmission will be repeated if necessary.
If a failure correction is not necessarily required (e.g. for voice services) or protocols of
higher layers take over the failure correction (e.g. a transmission mode like Z-INSYS ISDN
TA), the failure correction does not have to be performed on layer 2 again.
V.110 (layer 1b protocol)
point-to-multipoint connections and is usually used (automatically) in connections with
X.75 for data protection.
HDLC uses no control characters and is code-independent. To transmit data within HDLC,
the connection will be established first, then the data transmission takes place, and then
the connection will be terminated again. Failures are detected by using so called frames
and windows during transmission and the transmission will be repeated if necessary.
If a failure correction is not necessarily required (e.g. for voice services) or protocols of
higher layers take over the failure correction (e.g. a transmission mode like Z-INSYS ISDN
TA), the failure correction does not have to be performed on layer 2 again.
V.110 (layer 1b protocol)
V.110 is the description for a standard for transmitting data between an analog connec-
tion and an ISDN connection (data rate 1.200 to 38.400 bit/s, asynchronous) or between
two ISDN connections (data rate 56 or 64 kbit/s).
The task of V.110 is (in asynchronous mode) to depict an asynchronous data stream be-
tween 300 and 38.400 bps at the 64.000 bps ISDN data stream. Since always 64.000 bps
tion and an ISDN connection (data rate 1.200 to 38.400 bit/s, asynchronous) or between
two ISDN connections (data rate 56 or 64 kbit/s).
The task of V.110 is (in asynchronous mode) to depict an asynchronous data stream be-
tween 300 and 38.400 bps at the 64.000 bps ISDN data stream. Since always 64.000 bps