Fibre Channel and ATM: the physical layers

As more high bandwidth applications develop, system designers are looking for networks to deliver them higher performance than the ones in service today. Future applications will require higher bandwidth on both local and wide area networks. Two emerging standards are starting to be deployed that will address this problem by offering a road map of data transmission rates into the gigabaud range. Fibre Channel was the first to emerge, and was initially developed as a high-speed point to point interface for linking processors and their peripherals. As the standard evolved, it included different interconnect topologies that can make it into a network as well. Asynchronous Transfer Mode (ATM) is the other standard that is currently evolving. ATM has a goal of being the complete end-to-end public network, but is currently in the very early development stages. It promises to offer the user the ability to send a wide variety of applications, with "on-demand" bandwidth, and potentially seamless interconnect between LAN and WAN boundaries. This paper briefly overviews both of these standards with an emphasis on their physical layers, and then compares them.<>