Overview of client authentication

Microsoft Forefront Threat Management Gateway can allow access to resources based on user authentication. User authentication is used in a range of scenarios, summarized in the following table:

Authentication method	Outbound Web proxy requests	Incoming requests for published servers	Authentication Server
HTTP authentication: Basic	Yes	Yes	Active Directory or RADIUS LDAP (incoming requests only)
HTTP authentication: Basic	Yes	Yes	Active Directory, LDAP, or RADIUS
HTTP authentication: Digest/WDigest	Yes	Yes	Active Directory
HTTP authentication: Integrated (NTLM)	Yes	Yes	Active Directory
Client certificate	No (requests to upstream proxy server only)	Yes	Active Directory
Forms-based authentication	No	Yes	Active Directory, LDAP, RADIUS, RADIUS OTP, RSA SecurID

This section describes how Forefront TMG manages authentication. It provides information about authentication and delegation methods supported by Forefront TMG and how the authentication process is handled.