portsentry -- PortSentry will detect various network scanning<hr>
<a href="http://distro.ibiblio.org/pub/Linux/distributions/gentoo/distfiles/">http://distro.ibiblio.org/pub/Linux/distributions/gentoo/distfiles/</a><hr>
PortSentry will detect the following: - Strobe-style scans (full connect()
scans) - SYN/Half open scans.  - FIN scans.  - NULL scans.  - XMAS scans.
- UDP scans (not really stealth scans per se) - Any odd-ball packet with
flags not matching the above.
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