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FLM150ADM Optical Ring Transmission System (1991)

Integrating voice transmission with leased lines and taking the U.S. market by storm

Photo of FLM150ADM Optical Ring Transmission System

In the mid-1980s, with the drive towards standardization of optical transmission systems gaining momentum around the world, standardization of speed and multiplexing methods was being considered in America as well. The standard was referred to as Synchronous Optical NETwork, or SONET. The system would have to keep leased line services and other communications flowing even when failures occurred between telecommunications stations. Fujitsu renewed its network modeling methods to meet these demands and created a "ring" network system with built-in redundancy, thereby becoming the first in the world to commercialize SONET technology. This was the FLM Series, which had speeds of 150Mbps, 600Mbps, and 2.4Gbps.
Six of the seven U.S. regional phone companies adopted the FLM Series, which would go on to log sales of more than 1 trillion yen over the next 10 years and become the number one product on the market. The FLM150ADM Optical Ring Transmission System was one of the systems in this series. Fujitsu thus created the de facto telecommunications standard in America.