The TCP sweep threshold interval is in microseconds. The
default threshold value is 5000. The valid threshold range
is 1000-1000000.
By using the default settings, if a remote host initiates TCP
connection to 10 addresses in 0.005 seconds(5000 microseconds),
the security device flags this as an TCP sweep attack, and
rejects all further new TCP connections initiated from that
host for the remainder of the specified threshold time period.
This attribute holds the TCP sweep attack threshold.