How to see how many online users are on my ASP.Net MVC3 website?

What's the easiest way to see how many users are currently online on my website?

I'd like to display and set this information inside of my _Layout.cshtml file.

I'm using the latest version of ASP.Net MVC3 along wi开发者_如何学运维th C#.

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Actually it can be handled in the same way as in ASP.NET.

Main scenario is to increment some static variable or variable in Application[] collection on Session_Start and decrease this value on Session_End to handle number of online users.

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Application state can be used in this case. Hold a global variable which increments on each new session and decreases on session expiry