The Simple and Protected Generic Security Service Application Program Interface (GSS-API) Negotiation Mechanism (SPNEGO) Extension is an extension to [RFC4178] that provides a negotiation mechanism for the Generic Security Service Application Program Interface (GSS-API), as specified in [RFC2743]. SPNEGO provides a framework for two parties that are engaged in authentication to select from a set of possible authentication mechanisms, in a manner that preserves the opaque nature of the security protocols to the application protocol that uses SPNEGO. SPNEGO was first defined in [RFC2478], which has been superseded by [RFC4178].
Sections 1.5, 1.8, 1.9, 2, and 3 of this specification are normative. All other sections and examples in this specification are informative.