NAME

       axlisten - monitor AX.25 traffic

SYNOPSIS

       axlisten [-8] [-a] [-c] [-h] [-i] [-p port] [-r] [-t..] [-v]

DESCRIPTION

       Axlisten  uses  SOCK_PACKET  facilities  to  provide  a network monitor of all AX.25 traffic heard by the
       system. Since KISS is implicitly promiscuous no special driver configurations are needed.

       This version displays standard AX.25, PE1CHL extended AX.25, NET/ROM, Rose, ARP, IP, ICMP, TCP  and  UDP.
       It also displays IP, TCP, ICMP, TCP and UDP encapsulated within NET/ROM frames. The program also displays
       AX.25 and IP encapsulated within an IP frame, but see RFC1326 for reasons not to do so.

       Axlisten makes an attempt at decoding some of the more common  routing  protocols.  RSPF  and  RIP  (both
       “normal” and G8BPQs RIP98) are traced. JNOS style NET/ROM node polls are also displayed.

       Axlisten can use colors to make the output more readable. The ncurses library is used to accomplish this.
       Color support defaults to being disabled, and the -c parameter is used to enable it.

OPTIONS

       -8        Indicates that the terminal is capable of printing 8-bit characters. This parameter is required
                 for the -i parameter to work.

       -a        Allow for the monitoring of outgoing frames as well as incoming ones.

       -c        Enable color support.

       -h        Dump  the  data  portion of the packet in both hexadecimal and ASCII. The default is to display
                 data as ASCII only.

       -i        Map IBM codepage 437 characters 128-158 to their ISO-Latin-1 equivalents.  This is a  hack  for
                 scandinavian users. This parameter is only valid when used with the -8 and -c parameters.

       -p port   Monitor  only  those  frames  received  on  a particular port, by default all AX.25 devices are
                 monitored.

       -r        Dump the data portion in a "readable" fashion, which is more  suitable  for  tracing  plaintext
                 AX.25 traffic. CR-LF conversion is done.

       -t        Don't print a timestamp on each dump line.

       -tt       Print an unformatted timestamp on each dump line.

       -ttt      Print a delta (micro-second resolution) between current and previous line on each dump line.

       -tttt     Print a timestamp in default format proceeded by  date  on  each dump line.

       -ttttt    Print a delta  (micro-second  resolution)  between current and first line on each dump line.

       -v        Display the version.

FILES

       /etc/ax25/axports

SEE ALSO

       axcall(1), mheard(1), beacon(1), ax25(4), netrom(4), rose(4), kissattach(8).

BUGS

       Axlisten  does  not  validate the checksums of frames that support them (ie IP), therefore corrupt frames
       will be displayed with bogus values. The MSS of a TCP frame that contains that option is not displayed.

AUTHORS

       Alan Cox GW4PTS <alan@cymru.net>
       Jonathan Naylor G4KLX <g4klx@g4klx.demon.co.uk>
       Phil Karn KA9Q <karn@qualcomm.com>
       Heikki Hannikainen OH7LZB <oh7lzb@sral.fi>
       Scott Miller N1VG <scott@opentrac.org>