NetworkActiv Port Scanner 4.0Free
Scan for TCP, TCP SYN and UDP open ports, ping addresses, and ports, perform whois queries or use traceroute commands all from a customizable graphical interface. The tool works with both wireless area networks (WAN) as well as with local area networks (LAN).
NetworkActiv Port Scanner is a network exploration and administration tool that allows you to scan and explore internal LANs and external WANs. Because of the versatility and choosable operating modes available in NetworkActiv Port Scanner, it may be used by experienced network administrators as well as by novices. NetworkActiv Port Scanner provides all the basic features that you'd expect in an advanced network scanner, but also provides many additional features and technologies, some of which being completely unique to this scanner. NetworkActiv Port Scanner provides scanning performance simply not found in other Windows based network scanners, but one will need to actually try it to understand just how fast a network scan can be.