Optical communication technologies have evolved enormously recently.

Ten years ago, it was typified by:

• Low bit rate and short distance optical transmission (ex.: 622Mb/s, 2.5Gbs @ 60km to 400km)
• Data processing done in the electronic domain at the network nodes
• ON-OFF intensity modulation and direct detection of NRZ/RZ coded bits
• "Optics" was not an important concern in the transmission system design since the optical fiber acted as a transparent medium;

Nowadays optical communication technologies are typified by:

• 10 - 100 Gb/s bit rates per optical channel
• Increasing numbers of optical channels multiplexed together in a same fiber, i.e., high channel count DWDM systems
• Data processing turning more and more into the optical domain by using ROADM's, OXC's, optical packet switching, integrated photonic circuits etc
• Phase, polarization and amplitude modulation of the laser light signals; coherent detection technology and sophisticated bit-coding schemes
• "Optics" has become a key concern in the transmission network design.

• Implications for telecom carriers:

• The above evolution means that nowadays the optical characteristics of the fiber plant must be accurately measured and precisely analyzed by expert professionals who bear deep understanding of optical communication technology and optical metrology.
  The fiber measurements and analysis results must then be knowledgeably entered in the network design process.
  Doing so, the transmission network will be not only properly designed but also have an o ptimized design which will incur in lower capex investments and lower operational expenditures during its lifetime. This shall lead to a higher ROI and a longer life investment, which are important concern s in our current fast-evolving technology world that obsoletes technologies and investments quite quickly.

• Implications for utility companies:

• With time, the transmission technologies of the past become less and less available in the market. So, not only they provide lower transmission capacity and inferior capabilities but they also become more expensive to install and operate.
  This forces utility companies, which may not require the highest-capacity state-of-the-art transmission technology, to follow telecom-pushed criteria when considering investments in optical transmission systems. This means that, in order to make optimized capex and opex investments, utilities should consider the same newest technologies made available in the market for the telecom market sector.
  This also means that utilities must have the same concerns and worries as telecom companies when dealing with their fiber network investments. Such points are easily understood by making a parallel with the computer industry. Although one may require for his application a processing speed of only 400MHz, he will find it hard to buy a computer nowadays with such a specification.
  Moreover, the initial cost and operating cost of such computer will turn out to be more expensive than the current 3GHz dual-core computer machines. This fact means that one will be better-off considering a more widely available state-of-art technology.
  Moreover, although his application may require only 400MHz of processing speed, newer applications are always appearing in the market and they are usually bandwidth-hungry, which is alright since bandwidth is increasingly cheaper due to those new transmission technologies developed for and operated by the telecom sector.

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