Researchers at Lucent Technologies' Bell Labs have demonstrated 10-Gb/s serial data transmission over multimode fiber for local area networks. They used a prototype multimode fiber designed by the company and an 850-nm vertical cavity surface-emitting laser. To simulate real-world conditions, engineers used three subpar optical connections and worst-case cabling stress effects. Despite these hurdles, they successfully transmitted 10 Gb/s over 300 m with an error rate less than one in a trillion. According to the company, the demonstration could pave the way for a viable, cost-effective commercial 10-Gb/s system for in-building local area networks.