--state NEW -j DROP (would be great)

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Hello,

Could somebody please explain the 'iptables -A INPUT -eth0 -m state --state NEW -j DROP' a bit more for me ? I understand that it won't allow any outside initiated inbound connections into a network. However occasionally if I'm doing a tcpdump we see things like:

21:04:48.935367 IP 82.29.180.221.15378 > 213.17.40.204.4154: R 0:0(0) ack 1 win 0 21:04:48.935447 IP 82.29.180.221.15378 > 213.17.40.204.4154: R 0:0(0) ack 1 win 0 21:04:48.935455 IP 82.29.180.221.15378 > 213.17.40.204.4154: R 0:0(0) ack 1 win 0 21:04:48.935537 IP 82.29.180.221.15378 > 213.17.40.204.4154: R 0:0(0) ack 1 win 0 21:04:48.935545 IP 82.29.180.221.15378 > 213.17.40.204.4154: R 0:0(0) ack 1 win 0 21:04:48.935629 IP 82.29.180.221.15378 > 213.17.40.204.4154: R 0:0(0) ack 1 win 0 21:04:48.935637 IP 82.29.180.221.15378 > 213.17.40.204.4154: R 0:0(0) ack 1 win 0 21:04:48.935812 IP 82.29.180.221.15378 > 213.17.40.204.4154: R 0:0(0) ack 1 win 0 21:04:48.935821 IP 82.29.180.221.15378 > 213.17.40.204.4154: R 0:0(0) ack 1 win 0 21:04:48.936045 IP 82.29.180.221.15378 > 213.17.40.204.4154: R 0:0(0) ack 1 win 0 21:04:48.936053 IP 82.29.180.221.15378 > 213.17.40.204.4154: R 0:0(0) ack 1 win 0 21:04:48.936153 IP 82.29.180.221.15378 > 213.17.40.204.4154: R 0:0(0) ack 1 win 0

What is that and shouldn't it be dropped ? Or is the : R 0:0(0) ack 1 win 0 part of it a already establish connection ? Although that's one of our IP's it's not active on our network.

Any ideas / advice  would be greatly appreciated !

Regards

Sylvan


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