The ARCNET Interconnect (AI) Series of fixed-port hubs were created to fill the need to expand ARCNET Local Area Network (LANs) by way of repeaters, links and hubs. Repeaters can extend a network using the same cabling technology. A link can mix two cabling technologies-functioning as a media converter. A hub can add a segment and give support for distributed star topologies. The AI can implement all three of these expansion methods depending upon the number of its ports. The AI2 provides two ports for repeater and link applications while the AI3 implements the hub function. However, the AI2 and AI3 utilize the same robust hub timing electronics found in Contemporary Controls MOD HUB of modular active hubs.