Insys ISDN Terminal Adapter 4.0 11-02-01-02-00.015 Manuale Utente
Codici prodotto
11-02-01-02-00.015
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Operating Manual INSYS ISDN TA 4.0
Version 2.02 – 01.04
go over the line, the protocol inserts fill bits into the data streamto level out differences
to 64.000 bps. The fill bits are extracted and thrown away at the remote terminal then.
The connection represents itself for the layers above level 1 as if only 38.400 bps would
go over the line really. V.110 slows down the ISDN speed to 300 bps theoretically. Practi-
cally this goes down to 9.600 bps.
In contrast to X.75, for which problems might occur with the access parameters, there
are fixed standards for V.110.
The bit rate (300 to 38.400 bps) has to be the same for both communication partners.
V.120 Protocol
to 64.000 bps. The fill bits are extracted and thrown away at the remote terminal then.
The connection represents itself for the layers above level 1 as if only 38.400 bps would
go over the line really. V.110 slows down the ISDN speed to 300 bps theoretically. Practi-
cally this goes down to 9.600 bps.
In contrast to X.75, for which problems might occur with the access parameters, there
are fixed standards for V.110.
The bit rate (300 to 38.400 bps) has to be the same for both communication partners.
V.120 Protocol
V.120 is the standard for asynchronous data transmission with 57.600 bit/s in ISDN.
V.120 can be compared with X.75 concerning the tasks. HDLC is also used for failure de-
tection for V.120.
PPP Protocol
V.120 can be compared with X.75 concerning the tasks. HDLC is also used for failure de-
tection for V.120.
PPP Protocol
The PPP protocol (point to point protocol) is a standard method for the transmission of
multi-protocol-datagrams.
An important protocol feature of PPP is the failure correction:
Failures, which occurred during the transmission, are detected automatically here. But
this failure correction results some more overhead. This is at least 8 bytes of additional
overhead per packet. But this will be compensated if either the line quality is poor or one
of the two computers is under heavy load.
Another feature of PPP is the LCP (Link Configuration Protocol):
This adjusts the connection settings. Among other things, the IP addresses are ex-
changed– even assigned if necessary (dynamic address assignment). The configuration of
such an interface is much easier using the LCP.
multi-protocol-datagrams.
An important protocol feature of PPP is the failure correction:
Failures, which occurred during the transmission, are detected automatically here. But
this failure correction results some more overhead. This is at least 8 bytes of additional
overhead per packet. But this will be compensated if either the line quality is poor or one
of the two computers is under heavy load.
Another feature of PPP is the LCP (Link Configuration Protocol):
This adjusts the connection settings. Among other things, the IP addresses are ex-
changed– even assigned if necessary (dynamic address assignment). The configuration of
such an interface is much easier using the LCP.
9.3 Frequent ISDN Error Messages
In case of a failing connection the exact failure reason is recorded in the protocol mem-
ory of the ISDN TA. The most frequent error messages are described here; a complete list
of the error messages follows below (see chap. 9.4).
Layer 1 protocol error
ory of the ISDN TA. The most frequent error messages are described here; a complete list
of the error messages follows below (see chap. 9.4).
Layer 1 protocol error
No physical connection to the ISDN network exists. Check the cable connection between
ISDN adapter and ISDN connection. Do you use a correct cable? Has the connection
socket been installed correctly? Is the ISDN network termination activated correctly? Are
there any other devices at the ISDN connection, which might be defective or block the S0
bus?
Layer2 protocol error, e.g. DTE address invalid, TEI invalid
ISDN adapter and ISDN connection. Do you use a correct cable? Has the connection
socket been installed correctly? Is the ISDN network termination activated correctly? Are
there any other devices at the ISDN connection, which might be defective or block the S0
bus?
Layer2 protocol error, e.g. DTE address invalid, TEI invalid
No connection to the ISDN network could be established. A wrong ISDN protocol could be
the reason. Is the ISDN protocol set to "1TR6" (German ISDN) , while your ISDN connec-
tion is a standard "DSS1" (Euro ISDN), or the other way round?
the reason. Is the ISDN protocol set to "1TR6" (German ISDN) , while your ISDN connec-
tion is a standard "DSS1" (Euro ISDN), or the other way round?