Preliminary Design of a Computer Communications Network Interface Using Intel 80 86 and 80 89 16-Bit Microprocessors.

This research describes the design of a Universal Network Interface Device UNID II which is intended for use in a computer communications network. The II distinguishes UNID II from the original UNID which was also designed and developed at the Air Force Institute of Technology. UNID IIs purpose is to lessen the time delays and development costs incurred by custom-designing network interfaces for each application. UNID II is a programmable interface and although different applications require different device dependent programming, UNID II hardware remains essentially unchanged. A requirements study shows that to handle a wide variety of interfacing situations, UNID II must perform node functions which include concentration, switching and routing, front-end processing, and user-terminal interfacing. The performance of these functions relieves network hosts from communication-specific software. The key design concept is the subdivision of UNID II into two independent subsystems which communicate through an area in shared memory.