I took this from a GFI advertisment

"As a system admin, we know you're turning over every stone to find tools that make your life easier. Help is at hand with our guide to the top 10 free network monitoring and analysis tools!


http://www.wireshark.com Wireshark kicks off our list, being a network protocol analyzer andcapture utility. Captured data can easily be sent to another application for analysis, or filtered within WireShark itself.


http://pandorafms.com/?lng=en If you want to keep an eye on your servers, applications and communications, look no further than Pandora FMS. It can be configured to create alerts based on specific events,nd send notifications to administrators.


http://angryip.org Angry IP Scanner Scans IP addresses and ports, finding live hosts and providing you with information about them.


http://microsoft-network-monitor.en.s... When you're looking to capture packet data to analyze network traffic, turn to Microsoft Network Monitor. It has support for over three hundred public and Microsoft propriety protocols, as well as a wireless Monitor Mode.


http://www.telerik.com/fiddler
 Fiddler captures HTTP between computers and the Internet to help with debugging. You see incoming and outgoing data, including encrypted HTTPS traffic, allowing you to test your website performance, or the security of your web applications.


http://www.netresec.com/?page=Network... Network Miner is classed as a Network Forensic Analysis Tool, and is used to capture packets. It then extracts files and images from that data, allowing you to reconstruct your users actions.


http://www.colasoft.com/capsa-free/ Another tool for monitoring, troubleshooting and analysing network traffic is Capsa Free. Not only does it have over 300 protocols, and the ability to create and customise them, but it's dashboard also allows you to see a summary of traffic stays, TCP/UDP conversations, and packet analysis.


http://www.softinventive.com/products... Total Network Monitor watches over your hosts and services, notifyingyou when something requires your attention.t's colorful interface lets you see what's wrong at a glance.


http://www.xirrus.com/Products/Networ... And don't miss Xirrus Wi-Fi Inspector which manages connections,locates devices, detects rogue access points, and has connection and speed quality tests.


http://www.zenoss.org Lastly, Zenoss Core keeps an eye on your applications, servers, storage, networking and virtualization giving youperformance and availability stats. It also has an advanced notification system.


http://technet.microsoft.com/en-us/sysinternals/bb545021.aspx
The Sysinternals site was created in 1996 by Mark Russinovich and Bryce Cogswell to host their advanced system utilities and technical information. Whether you’re an IT Pro or a developer, you’ll find Sysinternals utilities to help you manage, troubleshoot and diagnose your Windows systems and applications.



With so much pressure on IT departments, can you afford not to take advantage of any free help you can get?"