Attempt to detect TCP and UDP port scans. This match was derived from Solar Designer's scanlogd.

--psd-weight-threshold threshold
    Total weight of the latest TCP/UDP packets with different destination ports coming from the same host to be treated as port scan sequence.

--psd-delay-threshold delay
    Delay (in hundredths of second) for the packets with different destination ports coming from the same host to be treated as possible port scan subsequence.

--psd-lo-ports-weight weight
    Weight of the packet with privileged (<=1024) destination port.

--psd-hi-ports-weight weight
    Weight of the packet with non-privileged destination port.