I’ve been doing a fiber update for ELECTRICAL CONTRACTOR every January for 16 years. I enjoy sitting back and taking an overview of the current fiber optic technology and markets, distilling it down to what I see as the most important topics and reporting it here. This year is a bit different.
Recently, I went to a TIA Standards meeting and watched three committees spend most of their time on topics other than technology before adjourning early. One committee spent most of its time with a discussion of polarity in multifiber connectors, a subject that has been discussed ad nauseum for a decade or more without resolution.
In many ways, this is good. The technology is stable, so contractors and installers can invest in tools and test equipment with confidence that they will not become quickly obsolete. It’s time for equipping and training crews to deal with the technology we’ve seen develop and mature over the last few years like microtrenching and blowing microcables into microducts (that is a lot of micros in one sentence!) or fusion splicers for splice-on connectors.
On the applications front, we’re not seeing anything really new, but we are seeing some ups and downs that demand our attention. Here too, factors other than technology may affect the performance of these markets.
Data centers continue to be a giant market for fiber optics and a great opportunity for electrical contractors who install fiber. However, these are not your father’s data centers. They probably are not what you have read about either. Data centers are no longer dominated by vendors of switches and servers or cabling. The big data center operators (Amazon, Apple, Facebook, Microsoft, etc.) have taken control of their designs.
Through a consortium called the Open Compute Project (OCP), they have designed their own electronics and made the designs “open source.” Anyone interested can download the designs, build the electronics and run them on the OCP open source software. These data centers are already running connections at 100 gigabits per second (Gbps) over single-mode fiber and are testing links at 200 Gbps and 400 Gbps. They can test and upgrade electronics that use single-mode fiber without having to upgrade the fiber, of course, which is why they converted to single-mode several years ago.
Why multimode fiber cabling for 40 Gbps over eight parallel fibers is still being discussed baffles me. Recent data shows 40 Gbps never has taken off. There has even been a new OM5 multimode fiber standard written to allow wavelength division multiplexing for 100 Gbps, but it’s not cost competitive with single-mode. It’s time to move on—certainly for any links with speeds over 10 Gbps. Single-mode is the logical solution for today (and tomorrow) without replacing the cable for an upgrade. And, single-mode fiber is unlikely to change. What we use today is essentially the same as we used 30 years ago.
Single-mode fiber is also gaining a big foothold in LANs. Many schools, hospitals and hotels have embraced passive optical LANs using fiber-to-the-home (FTTH) technology. The high volume of FTTH connections makes FTTH much cheaper than traditional LANs to install and cheaper to operate. The other factor here is wireless. LANs are now expected to support Wi-Fi throughout a building, and new hardware allows connecting cellular wireless. The old techniques used for cellular distributed antenna systems in buildings look like they will be replaced by antennas that connect up to the LAN like wireless access points.
Single-mode fiber is, of course, the fiber used in outside plant applications, and most of those applications are growing at healthy rates. Telecom companies are not the only ones scrambling to install enough fiber. Private companies are building FTTH and metropolitan networks. Electrical utilities are building more fiber to control their grids, implement microgrids and add local storage. Cities are building infrastructure for intelligent traffic systems, video surveillance and leasing to private companies.
The fastest growing application for cities is the expansion of cellular systems using “small cells,” low-power cell sites that cover less than one-tenth the area of the big cell towers. Small cells are the key to better urban cellular coverage and upgrades to 5G technology. In spite of all the hype, 5G is a long way from becoming a standard but is certainly driving investment in wireless.
A city the size of Los Angeles will need 8,000–10,000 small cells for adequate coverage. Cities like that are being besieged by cellular service providers to permit all these small cell sites, usually on top of street lights or traffic signals. Of course, every site needs power as well as fiber connections.