Useful Network Tools

Useful Network Tools

Packet capture (Wireshark)

 Ethereal, a classic packet analysis software, has become an open source project and has been renamed to Wireshark. Although it is free software, it has a lot of functions. It supports not only Windows but also various operating systems such as Mac OS X and Linux.

 It's a reassuring tool for network engineers to help with network troubleshooting. You can capture the raw packets that are actually flowing on the network and check the contents of the packets.

Below is a capture from an older version of Wireshark, but as you can see we can see what's inside the packet.

It is displayed in different colors, making it very easy to see.

Various network information survey software (NetEnum5)

"NetEnum" is free software for investigating device information in a LAN.

You can get various information about PCs and printers in the specified range.


・Create a list of hosts, IP addresses, MAC addresses, and comments
・Enumerate hosts recognized by the Windows network
・Specify workgroups and domains
・Enumerate hosts that can be pinged Timeout, TTL, thread execution interval specification
・Choose from multiple network cards and specify
・MAC address, vendor acquisition selection specification
・Login user acquisition
・OS type acquisition
・Packet capture port scan
・Simple packet capture function
・TCP/UDP List port connectivity
・Bulk scan of multiple hosts (if HostSonar is already registered)
・I/O packet dump (binary/ASCII) of hosts running NetEnum

Also, various network commands can be executed.

DOS command/command execution function

Port Scanner (Zenmap)

Zenmap is a GUI version of Nmap, the famous port scanning tool. It is developed as an open source and is highly functional but available for free.

It works on multiple platforms such as Windows, Mac OS X, and Linux.

For detailed usage, please refer to the Nmap reference guide.

Below is a capture of a much older version.

IP calculator

 It is a tool that can calculate the number of hosts and subnets from the IP address and subnet mask. You can also check it in binary notation. It is convenient because you can check the list of network addresses.

  • 32-bit display
  • IP address class (A to C)
  • IP address type (global or private)
  • Number of hosts that can be used
  • Number of subnets
  • Network range of input IP address
  • Wildcard mask
  • Network address List
  • multiplier display
  • CSV file output