PuTTY is a very useful network utility for administrators and developers alike. It has it's own Telnet client, SSH Client, Serial Terminal Client built in and even allows you to setup SSH tunnels. It's also open source which we absolutely love here at RexFault.NET. I use this tool every day and honestly if it ever goes away I'd be very upset as it makes my life so much easier.

This is a web based OUI lookup tool from the developers of WireShark. If you don't know what a OUI lookup tool is, basically the first 3 bytes of a MAC address (6 bytes in total) create what is known as a OUI (Organizational Unique Identifier). The OUI is specific to each manufacturer of MAC addresses and there is a large database out there of known OUIs. This is great because if we are looking for a specific device on the network such as a AXIS camera then we can lookup an unknown MAC address with this tool and see if it is a AXIS device or not.

Wireshark is a great tool for capturing packets on a network. It allows us to catch raw data as it leaves and enters our computer so we can troubleshoot data issues or investigate what a specific program is doing on the network.

Angry IP Scanner is a great tool for finding devices on your network. I use it all the time to find cameras and rogue devices someone attached that I'm not aware of. It will do a basic portscan as well and tell you what common services are also running on the device as well as what type of network card it is using.