In a message written on Sun, Mar 25, 2012 at 12:37:24PM -0700, JC Dill wrote:
their future is very uncertain. Can you promise that fiber has a *feasible* lifetime of 20-50 years? Maybe in 5-10 years all consumer data will be transferred via wireless, and investment in municipal wired data systems (fiber and copper) becomes worthless.
You have offered a two part problem. The initial question is, will fiber put in the ground today still be able to do something useful in 20-50 years. I believe the answer to that is yes. There is fiber that was installed in the early 1980's that is still in use today. It's predecessor technology, copper wires to the home, has been in use far longer and with today's DSL technolgy has done far more than ever intended. High quality transmission media in the ground has long life, and new, well designed fiber would be no exception. The second part of your question is really "might fiber be replaced with some disruptive technology?" That is always a risk, but I actually think the avenues for advancement are few. Wireless of some type is probably the only viable competitor, and it's anything but cheap at scale. The real way to address the second part is to look at the outgoing technology, copper/dsl. Even though phone lines were designed to just carry 8khz voice, we've found it far cheaper and easier to design DSL technology around those properties rather than replace it with fiber or wireless. The reason? Build cost mostly. Diging to bury new fiber is expensive, and even with wireless permitting new transmitter locations and spectrum are very expensive. Can I _guarantee_ no better technology will come along? No. However I would posit even if it does come along the life span of fiber is still 20 years just due to the build cost and timeframe of the new tech. It's if it doesn't come along the timeline grows to more like 50 years. There's risk in any technology investment, however I think having a high bandwidth, high reliability, cheap to operate pipe into the home will always have enormous value, and right now fiber is the best tech to that and thus the best place to invest. -- Leo Bicknell - bicknell@ufp.org - CCIE 3440 PGP keys at http://www.ufp.org/~bicknell/