An embodiment of the invention incorporates, or encapsulates, authentication mechanisms into an initiation phase of a transmission protocol session. In a preferred embodiment, Extensible Authentication Protocol (EAP) authentication steps are included in the three-way handshake of a request to establish a Transmission Control Protocol/Internet Protocol TCP/IP) session. An EAP authentication session request can be designated within the standard Transmission Control Protocol (TCP) segment by using unused flags in the segment header. Another way to designate the request is to include a predefined option value in the header.