I previously wrote a blog post about how hard drive performance has been increasing slower than the rate of change of Moore's law which means that hard drives have become relatively much slower over the past 15 years.

Another related and potentially more significant trend is that fiber bandwidth speeds have been increasing faster than Moore's Law over the past several years.  Although the data on this trend is much harder to find, I did find this reference at the Moore's Law article on Wikipedia:

Data per optical fiber. According to Gerry/Gerald Butters,^[15][16] the former head of Lucent's Optical Networking Group at Bell Labs, there is another version, called Butter's Law of Photonics,^[17] a formulation which deliberately parallels Moore's law. Butter's Law ^[18] says that the amount of data coming out of an optical fiber is doubling every nine months. Thus, the cost of transmitting a bit over an optical network decreases by half every nine months. The availability of wavelength-division multiplexing (sometimes called "WDM") increased the capacity that could be placed on a single fiber by as much as a factor of 100. Optical networking and DWDM is rapidly bringing down the cost of networking, and further progress seems assured. As a result, the wholesale price of data traffic collapsed in the dot-com bubble

I ran into Marc Verdiell who is a world-class fiber data communication expert and was able to ask him whether he was seeing such a dramatic shift in fiber bandwidth and he confirmed that the bandwidth potential for fiber is effectively unlimited as there are many, many colors of light that you can theoretically transmit down a piece of fiber.  (Of course, the technology to make this happen gets extremely complex which will keep experts like Marc busy for many years.)

I am seeking to understand this further, but these initial pieces of information suggest that we are in for continued, dramatic increases in network bandwidth in the coming years -- at a rate faster than the doubling-every-two-years realized pace of Moore's law. 

When combined with the long term trend that hard drive performance is increasing at a rate slower than Moore's Law, the clear result is that high performance and large scale data storage systems will evolve to designs based on reading to and writing from large numbers of hard drives simultaneously over high speed network connections.

Chris