the discussions have been lively and informative, i hope we can keep up the momentum and pursue other ICT related issues with such passion, in this reagrd, i pulled up some background info on the advantages of OFC for the people who may not be well versed with the topic. here it is, advantages of OFC Noise Immunity Noise immunity is one of the most useful features of fiber optics in industrial applications. In environments where electromagnetic interference is prominent and unavoidable, fiber optics are unaffected. While cables are normally contained in protective sheaths and often run inside conduit, there is no need to physically isolate fiber optic cables from electrical cables. This makes cable routing simpler. Electrical Isolation The problem of ground loop noise and common mode potential differences is eliminated by the use of fiber optic cables. Field signals, generated by devices floating at high potentials, can be coupled to other equipment at much lower potentials without the risk of damage. This is particularly desirable in industrial applications. Low Error Rates When properly designed to provide adequate signal levels at the receiving end of the link, a fiber optic system provides very low bit error rates. Safe for Use in Hazardous Areas Fiber optic links can be used to couple signals into areas with potentially explosive atmospheres without a risk to delivering or storing sufficient energy to ignite an explosion. This makes fiber optic technology particularly useful when designing intrinsically safe systems. Wide Bandwidth Fiber optic cables can carry very wide bandwidth signals, well into the GHz range. Many individual, lower bandwidth signals can be multiplexed onto the same cable. In commercial systems fiber optic cable often carries a mixture of signal types, including voice, video and data all on the same fiber. Low Signal Attenuation Optical fibers do exhibit some attenuation due to absorption and scattering. However, this attenuation is relatively independent of frequency, a factor that is significant in copper cables. Light Weight, Small Diameter Because many signals can be multiplexed onto one fiber, cables tend to be smaller and lighter. This makes installation easier. No Crosstalk Since fibers do not pick up electromagnetic interference, signals on adjacent cables are not coupled together. Inherent Signal Security For applications where signal security is a concern, optical fiber is an excellent solution. Fiber optic cables do not generate electromagnetic fields that could be picked up by external sensors. It is also more difficult to 'steal' signals by spicing into optical fibers than it might be with conventional copper wiring. regards becky Rebecca Wanjiku, journalist, p.o box 33515, Nairobi.00600 Kenya. Tel. 254 720 318 925 blog:http://beckyit.blogspot.com/ --------------------------------- Need Mail bonding? Go to the Yahoo! Mail Q&A for great tips from Yahoo! Answers users.