3.1.1 Abstract Data Model
This section describes a conceptual model of possible data organization that an implementation maintains to participate in this protocol. The described organization is provided to facilitate the explanation of how the protocol behaves. This document does not mandate that implementations adhere to this model as long as their external behavior is consistent with that described in this document.
The MESSAGE_TYPE enumerator specified in section 2.2.6.1 lists all NEGOEX message types. A GSS-API context token for NEGOEX consists of one or more NEGOEX messages. If there is more than one NEGOEX message, these messages are concatenated together. The smallest data unit for NEGOEX to compute the checksum for negotiation protection is a NEGOEX message. Note that NEGOEX is not a GSS-API mechanism itself and that the initial NEGOEX context establishment token does not follow the mechanism-independent token format specified in [RFC2743] section 3.1.
The object identifier of the NEGOEX within SPNEGO is specified in section 1.9.1.