a)Fiber can handle much higher bandwidths than copper
b)Fiber repeaters are needed only about every 50 km on longlines, versus about every 5 km for copper
c)Fiber also has the advantage of not being affected by powersurges, electromagnetic interference, power failures, orcorrosive chemicals in the air
d)Fiber is thin and lightweight
–One thousand twisted pairs 1 km long weigh 8000 kg
–Two fibers have more capacity and weigh only 100 kg
e)Fibers do not leak light and are quite difficult to tap,excellent security against potential wiretappers.