asp.net application + single sign on

I want to implement single sign on in my asp.net web application. Scenario is something like below:

1. user will get registered / sign 开发者_如何学JAVAup at "account.example.com"
2. there will a link to "professional.example.com"
3. when user goes to this link (step 2), they must remain logged in over here.

What is the best solution for this?

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You want to set the Domain property on the cookie object to ".example.com" and it will work for any sub-domain of "example.com".

If you're using ASP.NET's forms authentication, this article is a good place to start to find out all the options for configuring it.

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If you are using Forms Authentication you need to set your forms and machinekey sections in web.config to be identical.

Here is a good link -> Forms Authentication Across Applications