Is there a sample of pppd's active-filter option?
It's purpose to distinguish between packets that should keep the ppp connection up and those that shouldn't.
active-filter "inbound and not icmp and not udp and not icmp[0] != 8 and not tcp[13] & 4 != 0 and not tcp port 135 and not tcp port 137 and not tcp port 138 and not tcp port 139 and not tcp port 445 and not port 5353"
Linear Mode
