* Added ACK scanning. This scan technique is great for testing firewall
rulesets. It can NOT find open ports, but it can distinguish between
filtered/unfilterd by sending an ACK packet to each port and waiting for
a RST to come back. Filtered ports will not send back a RST (or will
send ICMP unreachables). This scan type is activated with -sA .
* Documented the Window scan (-sW)
* "Protocol" field in output eliminated. It is now printed right
next to the number (/etc/services style). Like "22/tcp".
* Added --resume option to continue a large network scan where you left off.
It also allows you to start and stop for policy reasons
Sometimes you need speed, other times you may need stealth. In some cases,
bypassing firewalls may be required. Not to mention the fact that you may
want to scan different protocols (UDP, TCP, ICMP, etc.).
You just can't do all this with one scanning mode. Thus nmap
incorporats virtually every scanning technique known of.
See the nmap homepage at http://www.insecure.org/nmap/index.html
