Microsoft Network Monitor 3 is a network protocol analyzer that can capture network traffic for further inspection by a network administrator. It supports regular expression filters, scriptable parsers, custom data types and other advanced features. Network Monitor 3 can simultaneously capture packets on multiple network adapters and provides real-time display as well as frame and tree view to manage the captured data.

Network Monitor 3.1 can co-exist with Netmon2.x. NM3.1 installs in %program files%\Microsoft Network Monitor 3, so there is no conflict. But it will require that NM3.0 be uninstalled first. The NM3.1 install will do this automatically for you.

For Vista, we have a new driver that supports new features available in the NDIS 6.0 driver. If you are using tools that rely on Network Monitor 2.x NPPTools, these tools will no longer work.

Capturing on Vista requires NM3.0 or NM3.1, as Netmon2.x does not capture properly on Vista.

Warning: Capturing with the NM3 GUI with conversations enabled can use up considerable amount of memory. This may cause a machine to become unresponsive. If you need to capture data for long periods of time, please use the included command line utility, NMCap, and the /DisableConversations switch.

The license of this software is Freeware, you can free download and free use this network monitoring software.