L-Expressnet is the communication suxbnetwork for the CNET local area network project of the CNR, Italy. Based on a single bus topology, it utilizes a simple and efficient virtual-token access protocol which provides ordered and collision-free transmission. The paper discusses the needs which led to L-Expressnet, describes the protocol, proves its correct operation, and compares its throughput-delay performance with those of other typical bus Protocols. A major advantage of L-Expressnet is that its implementation may be based on Ethernet standard transceivers and network interfaces.