Authenticate Using Windows Live ID
Microsoft Office Live Small Business provides server-side authentication using the Windows Live ID service. Different classes of users can be given different privileges. Users create sign-in credentials (an e-mail address and password) once, and then they can use the same credentials on any site that uses Windows Live ID for authentication. With Live ID, you can have sites remember the user's credentials from session to session. For more information about Windows Live ID authentication, read the article Windows Live ID Web Authentication 1.0 SDK.
If you create a Web page in Office Live Small Business, your page already uses Windows Live ID authentication.
Windows Live ID Credentials
E-mail accounts associated with the custom domain you create for an Office Live Small Business account are automatically registered as Windows Live ID credentials.
Hotmail.com and msn.com addresses are also automatically registered.
You can register just about any other e-mail address as Windows Live ID credentials. For example, you can register your existing yahoo.com or gmail.com e-mail address as your Windows Live ID e-mail address.
You can use the Windows Live ID credentials that you create for Office Live Small Business to be authenticated in Windows Live Messenger, Microsoft Hotmail, MSN Music, and other sites and services.
Authenticating Client Applications
If you want to work with the Office Live Small Business APIs from client-side applications, users must first be authenticated through Windows Live ID. You can use the Office Live Small Business Discovery Web service and Windows Live ID for client applications to provide this service. The Client Application Connection Code Sample provides an example and detailed instructions for authenticating a client application. For more information about Windows Live ID for client applications, download the Windows Live ID Client 1.0 SDK.