Providing Single Sign-On (SSO) in disjoint networks with non-overlapping authentication protocols

A method of enabling single sign-on (SSO) access to an application executing in an enterprise, wherein authorized, secure access to specific enterprise applications are facilitated via an enterprise-based connector. In response to successful authentication of an end user via a first authentication method, a credential associated with the successful authentication is encrypted to generate an encrypted user token. The encrypted user token is then for storage in a database accessible by the enterprise-based connector. Following a redirect (e.g., from a login server instance) that returns the end user to the enterprise-based connector, the encrypted user token is fetched and decrypted recover the credential. The credential so recovered is then used to attempt to authenticate the user to an application via a second authentication method distinct from the first authentication method. Typically, the first authentication method is an HTML form-based authentication initiated from a client browser, and the second authentication method is one of: NTLM, and Kerberos.