The HTTP Form protocol is a common approach to SSO authentication that can also qualify as a AAA method. It provides a secure method for exchanging authentication information between WebVPN users and authenticating web servers. As a common protocol, it is highly compatible with web servers and web-based SSO products, and you can use it in conjunction with other AAA servers such as RADIUS or LDAP servers. As with SiteMinder, the security appliance serves as a proxy for WebVPN users to an authenticating web server but, in this case, it uses HTTP Form protocol and the POST method for requests. You must configure the security appliance to send and receive form data.
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