The 'best' tool depends on your platform and goals.
If you need to scan the local LAN (that is, that equipment connected to the same switch as your host), you could use 'arp' (OSX/Linux, not sure about Windows).
To scan further abroad past the local wire you might try a port scanner which will brute force through IPs and look for connected hosts.
Are you trying to find cameras? There are higher level protocols designed to aid in that goal.
Angry IP scanners is a great little tool. We use that alot for finding available IP addresses.
Great suggestion, Chris. I learned about ARP from IPVM, and only later discovered that it's presenting the contents of the address resolution table specific to the computer that executes the arp command. Any particular device won't necessarily be aware of every other device on the network, when it hasn't beenn party to traffic involving other devices. It never occurred to me to do a broadcast ping before the arp -a.
Thanks for the suggestion!
Wire shark. Free and easy. I use it all the time as I get hear with addresses changed to strange private schemes.
Advanced IP Scanner has been my go-to for years. Solid programming with a "run but don't install" option for client environments. Lots of features. Free.
nmap would be the tool I use.
It's only going to list MAC addresses when they are on the same network.
You can easily update the OID vendor database (assuming you are a techie) and identify the vendor of the network card. This makes it fairly easy to find where my DHCP connected cameras, NVR's, laptops, desktops, mobile devices are...
It's normally a command line tool and available for Linux, Mac, Windows, etc... There's even a GUI available for Windows.
I use Fing on android or iPhone with a WiFi USB access point. Set up the access point for DHCP and connect the access point to any network and login into the access point with your phone. The is superfast and gives you everything you could possibly want to know about a network.
TP-Link Access Point
They have a Windows desktop version but it is not as user-friendly or polished as the apps.
Get in seconds a complete picture of the network you are in, including IP and MAC addresses, device vendors and ISP location.
Born from the experience of the famous Look@LAN, Fing relies on a fast, network engine. Currently available as a Mobile App (Android and iOS) and Desktop command-line tool (Windows, OS X, Linux), Fing is free of charge and Ads. We intend to support more platforms in the future, including a long-awaited Desktop GUI.
What does "Fing" mean? Originally, we thought that it would replace all your tools to Find andPing devices, so we made up the term "To Fing", meaning both finding a device and verifying what's on it. We grew fond of the name* and now we hope you'd adopt it too.
The Fluke OneTouch AT Network Assistant it a great tool for discovering devices and services on a network along with the ability to do various diagnostic tests. Depending on the model, it can do wired and/or wireless and even has the ability to do bandwith tests and wireshark captures.
The only bad part is that this is an expensive tool, so unless you have a regular need for network diagnostics, it may be hard to justify the costs.
Fluke Networks does have some other network tools, like the LinkSprinter and LinkRunner, which can help with network diagnostics, but these devices don't do device discovery.
FING is a great tool and it saves as history for that site as well.
IPVMU Certified | 10/15/15 04:01pm
for Linux: ip addr or ifconfig
For Windows: ifconfig /all