MAGNET is a Network Testbed (NTB) designed to evaluate the performance of local area network architectures and protocols supporting integrated services such as televideo, video conferencing, telephone, computer communication, and facsimile. The integrated local area network (ILAN) presented in this paper has been designed to support the research activities intended for MAGNET. An active slotted ring topology was chosen to implement adaptive sequential-type access mechanisms that are a function of the network loading. The ILAN is based on fiber optic technology with wavelength-division multiplexing of two 100 Mbit/s channels. The media-access protocol provides higher levels with the capability of implementing two modes of operation referred to as circuit-switching, and packet-switching modes, respectively. Provisions have also been made for implementing simultaneous scheduling as well as centralized and decentralized access control schemes. Finally, the reconfigurable structure of the network testbed enables the study of the reliability and availability of ILAN's.