Carries Ethernet or ATM data. Fiber-optic cable consists of glass fibers, allowing for significantly higher transfer speeds compared to copper. Data are transmitted in the form of light pulses injected by a laser or an LED. Fiber-optic cables allow for longer distances between connection points. Whereas 100 Mbit copper cable is limited to 100-meter or 300-foot lengths, a fiber-optic cable can extend to 8-km lengths. Also, because fiber-optic cables do not emit electro magnetic radiation, they seem to be the medium of choice in security-critical installations. The downside to fiber-optic technology use is that it is more expensive than copper technology. QUT Division of Technology, Information and Learning Support. Network Glossary. [Online, July 17, 2003.] QUT Division of Technology, Information and Learning Support Website. http://www.its.qut.edu.au/network/glossary.jsp.