If fiber only lasted 7-10 years, I will find myself busier than a one-armed paperhanger in about 3 years!
All of our fibers are glass - it has to be, plastics are too dirty...they would heat up and melt. As it is, a glass fiber can get pretty hot when there is video flowing through it....it'll sting ya.
I honestly don't know the lifespan of a fiber cable...I am sure it is more than 10 years. I am fairly sure that any cable failure will most likely be caused by a shovel/backhoe/disaster, than by it "wearing out" or breaking down somehow.

If I remember, I will ask around tomorrow, and find out how old the oldest section of fiber cable is in our area.

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D