The invention disclosed herein provides the basic operating capabilities of SNA data communications for host based application-to-application sessions across a packet switched network such as the Defense Data Network (DDN). The problem that is presented by the integration of these two technologies is that SNA is a connection oriented technology and DDN is a connectionless technology that requires an Internetting Protocol (IP) header on all information transmitted through the network and across multiple networks. One of the concepts of the invention is the definition of a localized SNA network to each SNA host by the channel attached Front End Processors (FEPs). These FEPs present an SNA PU4 definition to the host to allow it to carry out regular SNA sessions over the packet switched network to another host through its own respective FEP. The two FEPs working together imbed the SNA protocols in the IP datagrams and provide the proper SNA connections and control. This technique also allowed any host to access any other host for which it has authorization.