isdndecode(8)

NAME

isdndecode - isdn4bsd ISDN protocol decode utility

SYNOPSIS

isdndecode [-a] [-b] [-d] [-f filename] [-h] [-i] [-l]  [-o]
[-p filename]
           [-u number] [-x] [-B] [-P] [-R unit] [-T unit]

DESCRIPTION

The isdndecode utility is part of the isdn4bsd package and

is used to
provide the user with a detailed mnemonic display of the

layers 1, 2 and
3 protocol activities on the D channel and hex dump of the B

channel(s)
activities.

Together with two passive supported cards and an easy to

build cable it
can also be used to monitor the complete traffic on a S0 bus

providing S0
bus analyzer features.

The isdndecode utility is only available for passive sup

ported cards.

The following options can be used:

-a Run isdndecode in analyzer mode by using two passive

cards and a

custom cable which can be build as described in the

file
cable.txt in the isdn4bsd source distribution. One

card acts as
a receiver for the transmitting direction on the S0

bus while the
other card acts as a receiver for the receiving di

rection on the
S0 bus. Complete traffic monitoring is possible us

ing this
setup.

-b switch B channel tracing on (default off).

-d switch D channel tracing off (default on).

-f Use filename as the name of a file into which to

write tracing

output (default filename is isdndecode<n> where n is

the number
of the unit to decode).

-h switch display of header off (default on).

-i print layer 1 (I.430) INFO signals to monitor layer

1 activity

(default off).

-l switch displaying of Layer 2 (Q.921) frames off (de

fault on).

-o switch off writing decode output to a file (default

on).

-p Use filename as the name of a file used for the -B

and -P options

(default filename is isdntracebin<n> where n is the

number of the
unit to decode).

-u Use number as the unit number of the controller card

to decode

(default 0).

-x Decode Layer 3 packets with an unknown protocol dis

criminator.

-B Write undecoded binary decode data to a file for

later or remote

analyzing (default off).

-P Read undecoded binary decode data from file instead

from device

(default off).

-R Use unit as the receiving interface unit number in

analyze mode.

-T Use unit as the transmitting interface unit number

in analyze

mode.

When the USR1 signal is sent to a isdndecode process, the

currently used
logfiles are reopened, so that logfile rotation becomes pos

sible.

The decode output should be obvious. It is very handy to

have the following standard texts available when tracing ISDN protocols:

I.430 ISDN BRI layer 1 protocol description.
Q.921 ISDN D-channel layer 2 protocol description.
Q.931 ISDN D-channel layer 3 protocol description.

FILES

/dev/i4btrc<n>

The devicefile(s) used to get the decode messages

for ISDN card
unit <n> out of the kernel.

EXAMPLES

The command:

isdndecode -f /var/tmp/isdn.decode

will start D channel tracing on passive controller 0 with

all except B
channel tracing enabled and logs everything into the output

file
/var/tmp/isdn.decode.

SEE ALSO

isdnd(8)

STANDARDS

ITU Recommendations I.430, Q.920, Q.921, Q.930, Q.931

ITU Recommendation Q.932 (03/93), Q.950 (03/93)

ETSI Recommendation ETS 300 179 (10/92), ETS 300 180 (10/92)

ETSI Recommendation ETS 300 181 (04/93), ETS 300 182 (04/93)

ITU Recommendation X.208, X.209

AUTHORS

The isdndecode utility and this manual page were written by

Hellmuth
Michaelis <hm@kts.org>.

BUGS

Still one left.

BSD February 21, 2000

BSD