Cross-domain login in ASP.NET Website

Question

I have an ASP.NET Website with login page that redirects to default page in case of successful authentication. I have another ASP.NET site under another domain, where I need to place a login form, that will redirect already authenticated user to the default page of the first website. What is the best way of doing this?

Any help will be appreciated..

Answer 1

What you are after is single sign on. The mechanics of the succsesful login redirect are in the web.config

see here http://msdn.microsoft.com/en-us/library/eb0zx8fc.aspx

<configuration>
<system.web>
<authentication mode="Forms" >
  <!-- The name, protection, and path attributes must match 
       exactly in each Web.config file. -->
  <forms loginUrl="login.aspx"
    name=".ASPXFORMSAUTH" 
    protection="All"  
    path="/" 
    domain="contoso.com" 
    timeout="30" />
</authentication>
<!-- Validation and decryption keys must exactly match and cannot
     be set to "AutoGenerate". The validation and decryption
     algorithms must also be the same. -->
<machineKey
  validationKey="[your key here]" 
  decryptionKey="[your key here]" 
  validation="SHA1" />

Also look here: Asp.net forms authentication and multiple domains