LISTEN(1)

NAME
listen - monitor AX.25 traffic

SYNOPSIS
listen

DESCRIPTION

Listen 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 AX.25, NET/ROM, 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.

SEE ALSO
call(1), beacon(3), ax25(4), axattach(8)

BUGS
Listen 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 <iiitac@pyr.swan.ac.uk>
Jonathan Naylor G4KLX <g4klx@g4klx.demon.co.uk>
Phil Karn KA9Q <karn@qualcomm.com>