Check out the Internet Connectivity Evaluation Tool

[Paul]

Are you a home user network who's unsure whether your current internet router is capable of supporting some of Windows Vista's advanced networking features? Not to worry: the Internet Connectivity Evaluation Tool is here to help you out.
The Internet Connectivity Evaluation Tool is designed to be run on your home network behind a home internet router (NAT). It runs a series of tests that will let you know if certain advanced features in Windows Vista will be supported behind your current router. If the tests show your router does not support the advanced networking features in Windows Vista, they'll further help you by giving you a better understanding of what features to look for when purchasing a new router that will take full advantage of Windows Vista.
The Internet Connectivity Evaluation Tool runs the following set of tests on your router:

• Basic Internet Connectivity Test
• Network Address Translator Type
• Traffic Congestion Test
• TCP High Performance Test
• UPnP Support Test
• Multiple Simultaneous Connection States Test

At the end of the test, you can get a detailed report of the test's findings. If your router doesn't pass the tests, the site gives you recommendations on other routers that are Certified for Windows Vista. Give it a try and see how your current hardware stacks up.
http://windowsvistablog.com/aggbug.aspx?PostID=483581

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