This is a very fast and small IP scanner. It has many options, such as the ability to resolve host names, check for open ports, scan dead machines. It contains many features, such as configurable scanning columns, multiple port scanning, various export formats, and plug-ins.

It’s a GUI-based Java program that, in its newest generation, is cross-platform (should work on at least Windows, Linux and OS X). I’ve tested it on Windows and Linux. It didn’t need any installing on Windows; it’s just a single binary (950k). The IP Scanner does ping sweeps and some port scanning.  TCP and UDP aren’t raw because the author wants to make clear that it’s not a so-called “hacktool”.

A big design difference between Nmap and the IP Scanner is that the IP Scanner is multi-threaded instead of doing I/O multiplexing with select. You can choose a maximum number of threads for it to run at a time (it uses one for *every* host). For host specification it can take a range (you give start and end addresses), or you can specify a netmask in address form (e.g.255.255.255.0) or CIDR notation (e.g. /24) and it will set the end address based on the start and netmask.  It can also read from a file, or produce random addresses.  What’s cool about their random address generator is that you give it a maximum number of addresses to produce, a base IP, and a netmask to narrow down the scope (give it 0.0.0.0 to behave like Nmap).  It doesn’t avoid reserved IPs like Nmap does, however.

It doesn’t seem to support IPv6, but it doesn’t stop a scan from going with an IPv6 address. It can do TCP, UDP or ICMP pings, except of course on XP SP2 the ICMP ping won’t work due to broken raw sockets. One thing I do like about it is the ability to narrow down the random
IP generation to a given base IP and netmask.  This may not be easy to implement in Nmap (since a user may or may not want a reserved IP, and
the random IP generation code would have to be changed to allow for this), and probably not worth it.  For example, if you wanted random IPs in the range of 192.*.*.*, should 192.168 be chosen or not?  It’s still pretty cool, though.