Aprsdigi is a specialized Amateur Packet Radio (AX.25) UI-frame digipeater for
the Automatic Position Reporting Systems, APRS(tm). It uses the Linux kernel
AX.25 network stack as well as the SOCK_PACKET facility to listen for packets
on one or more radio interfaces (ports) and repeat those packets -- with
several possible modifications -- on the same or other interfaces. Aprsdigi can
also use the Internet to tunnel connections among other APRS digipeaters and
nodes using IPv4 or IPv6 UDP unicast or multicast.