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Passive optic LANs: Prospects for your fiber optics business (p. 2)

We are back with our interview with our special guest, Jim Hayes, President of the Fiber Optic Association. The first part was devoted mostly to technical aspects of passive optical LANs, and now we are going to talk about POL business.

Jim Hayes tells about Passive Optical LAN

Alexei: For our readers probably the most interesting aspect is economics of PONs, expenses involved, etc. Motorola claims that capital expenses are cut by 50%, Tellabs’ number for that is even higher, 70%. Can you comment on the numbers?

Jim Hayes: As I said earlier, the numbers are not absolute, of course, and I cannot answer for Motorola and Tellabs. I would say all of this is dependent on the actual installation—how many users and how big a geographic area you cover—and what you compare it to. A POL is a “Level 1 +Level 2” network—it includes the switches and cabling to provide Ethernet. Some people only want to consider cables to cables, but that’s irrelevant, you need to consider it as part of the network. Furthermore, traditional LANs have been priced very high for fiber—a Cat5 port may cost $5 on a switch, a multimode port $500 and a singlemode port $5000! That’s hardly comparable to the cost of FTTH hardware where a typical FTTH subscriber can be connected for what a traditional switch supplier wants for a multimode port! Some cases like Sandia Labs are no-brainers because you need SM to connect various facilities. Others are non-optimal because they are updates in buildings with cabling systems already, but there is another advantage for an OLAN—it takes so little space you can install it before removing all the old copper. Just have a look. And yes, it is good income to recycle! Sandia made $80,000 off recycled cable. The cost of copper will likely be going up and make this recycling even more attractive economically. Besides, fewer electronics means less power. No power or AC in the telecom closet. AC is half the energy consumed in most LANs! That is why electricity expenses are cut about 80%. Even more, the space occupied by the equipment is reduced drastically, sometimes tenfold. One more on POL business. To date, the major markets have been in large LANs, like government agencies, schools and school systems, college campuses, where there are large numbers of users or large geographic areas. We know of several cities considering them for their municipal networks, perhaps in conjunction with a city-owned FTTH system. Now structured cabling standards are adapting to passive OLANs by adding in the splitter so centralized fiber with a splitter becomes a passive OLAN. The alternative is active Ethernet on a centralized fiber architecture using singlemode fiber and P2P (point to point) FTTH hardware. OLANs will be integrated into structured cabling architecture and standards but should over time predominate in larger LANs with at least 100 users, the more the better. That is where they are feasible now, though I can say with fiber optics booming in general the number will go down soon.

Alexei: Do you think that POLs are more interesting for well-developed regions with excellent infrastructure, like most of the US, Western Europe, and cities like Shanghai, Moscow, Singapore?

Jim Hayes: Yes, but only because there is probably a ”dark fiber” network in the cities that allows building citywide networks. I would say that with POL technologies those well-developed regions do not have to be so tightly packed as, say, in Hong Kong. A bank can have several offices, a few miles between them, and still cover it with one relatively cheap and advanced LAN. Besides, such cities are just places where the money goes, swirls, and boils. You want profits, you go to such places.

Alexei: What about installation personnel training and maintenance personnel training?

Jim Hayes: Of course, designers need to understand the new architecture of OLANs, where to place splitters, how to spec singlemode fiber and other related components. If you are familiar with optic fiber, the installation process is simple—tiny cables, prefab cables or prepolished/splice connectors. Installers can learn it in a couple of days. Again, most likely you will need better OTDRs than you do now, because of many connectors and splitters. If you are new fiber optics in general, then you have to learn how to splice, how connectors work, etc. But it is not rocket science.

Alexei: But you still have to pay for new equipment?

Jim Hayes: Right, you cannot reuse copper LAN equipment, of course. But again, if you compare the cost of upgrade, POL is much cheaper.

Alexei: Now about upgrades. According to Tellabs, POLs eliminate future infrastructure upgrades. Sounds too good to be true, no?

Jim Hayes: Well, I would put it more modestly: POLs are as future-proof as you can get today. The same fiber for a gigabit POL can be upgraded to 10G – the standards and products are already here. WDM POLs (wavelength division multiplexing) allows another 100X upgrade – again standards are being developed – and that takes us to 1Tb/s! When LANs go to speeds over terabits per sec, you may need an upgrade. Some time in the future you will definitely have to upgrade. To what? I don’t know, maybe to photon torpedoes or transporter beams, but it is not Godfather, it is Star Trek already (laughing).

Alexei: Tellabs claims that the POL technology “greatly reduces the potential for Denial of Service (DoS), redirects or other malicious attacks”. How is it done?

Jim Hayes: They are routinely connected to the Internet at higher speeds than traditional LANs which helps. More ISP bandwidth makes DoS attacks harder.

Alexei: So passive optic LANs are faster?

Jim Hayes: Yes, definitely. 2.4Gb/s down, 1.2 Gb/s up today, 10G coming soon.

Alexei: Our main audience is mostly engineers who deal with regular optical fiber. If they decide to get into POLs, what new things do they have to learn? What new skills to acquire?

Jim Hayes: Many skills from regular OF, particularly FTTH, can be used with POLs. Splicing, termination, design and measurement are just a few to mention.

Alexei: Let’s take a regular medium or small business, or even an individual. Now they are building networks with UTP. How necessary (or interesting) will the POL technology be for them in the nearest future?

Jim Hayes: As I said before, currently a POL is viable if it has over 100 users, and that number will decrease as new POL equipment for smaller LANs is announced. A good example is a university campus, a big international airport with many units, surveillance systems, etc, or an office of a big agency or company, especially if it spreads out several miles. But the costs of fiber and optic components are going down and more new engineers acquire the necessary training. The cost of measuring equipment may still be an issue for some, as a decent OTDR can cost over ten thousand dollars. But it is also going down. I would advise fiber engineers and technicians to really consider getting closer to passive optic LANs if they want to survive in the business. Besides, many of their existing skills are quite reusable. What they need to actually learn is mostly how to design and document passive optic LANs. A couple of days study and they will be ready. Again, one of the good sources of free information on that is the FOA site. You live and learn, when you stop—you die. Now a thing to learn is passive optic LANs.

Alexei: Well, our interview turned out to be almost all praise to PONs. Still, what is the main disadvantage of them, in your opinion?

Jim Hayes: Just that they are new and unfamiliar to many users. Also traditional LAN switch vendors see them as a threat to their business. Anyway, as I put it earlier, it is a thing of the future. So I would really advise fiber optics engineers to review their OTDR fleet and get some training in the subject.

Alexei: Thank you ever so much, Jim. You shared a lot, and we would be happy to be of any service for you and your Association.

Jim Hayes: You are welcome. Some day, and that day may never come, I will call upon your site to do a service for me.

Alexei: We would be glad to be of any service to you.

Passive optic LANs: Prospects for your fiber optics business (p. 1)

Fiberizer is developing software for fiber optics engineers, and we want to share latest news and trends with our respected users. We are starting with an interview with Jim Hayes, President of the Fiber Optic Association, who kindly agreed to give an interview to our site.

A-Sk: Hello there, Jim. Thank you once again for agreeing to be a guest of As we called it before, the main topic of our interview is passive optical LANs and the global repercussions they are going to make very soon. I am sure this will be a tasty and nutritious professional lunch (or dinner, depending on the time zone) for every engineer whose job is related to either fiber optics or to LANs. But for the starter, can you please tell us a bit about yourself and your organization, the Fiber Optic Association (FOA)?

Jim Hayes: Hi, Alex. I am very glad to be a guest of Fiberizer. I had a nice talk with your bosses, very interesting from the professional point of view. When they asked me for this interview, I did not think long.

A-Sk: So... How would you define yourself?

Jim Hayes: Sounds a bit like a psychotherapist's question (laughing). Well, for the interview I would say I am a techie entrepreneur with a long and strong interest in fiber optics. Back in 1981 my wife Karen and I started one of the world's first fiber optic test equipment companies, Fotec which was sold to Fluke in 2001. Now I preside the FOA, and, when I have some time, a little consulting. It is actually all on my personal page, Both work and play about me, all there.

Jim Hayes

A-Sk: Ok, I got the message. No more personal questions, only business. And it is a family business, right? So I am going to make you an offer you cannot refuse. Tell us about the FOA.

Jim Hayes: The FOA is a non-profit professional organization for fiber optics technicians, engineers and users started in 1995 to promote fiber optics through education, certification and standards. We have over 200 FOA-approved schools in 40 countries around the world who offer fiber optic training.  We also provide free online training and self-study resources, publish quick-start guides, industry standards, other important documents, and news, of course. FOA certification programs are recognized by the US Department of Labor and many other organizations and companies worldwide. We strongly believe that professionals must share their knowledge, so here I am, ready to answer your questions, and possible questions of the readers which can ensue.

A-Sk: Thank you again for sharing. Recently the FOA became a member of the Association for Passive Optical LAN. The Association unites key players on the market, like Corning, Leidos, 3M, IBM, Tellabs. Why did those huge corporations raise the topic so high? Why did the FOA, a not-so-big-but-very-experienced organization, join the pool?

Jim Hayes: Some people think we’re “big”—we’ve certified over 45,000 techs worldwide! FOA joined APOLAN because we have been promoting optical LANs (we call them OLANs) for many years. Passive optical LANs (POLs) have a potential huge enough to attract major players, and the market for OLANs is HUGE! They will help educate and promote the concept to the end users who are potential customers. As for our Association, we do believe that the subject will be of high importance for fiber optics testing and training, in the very near future. That is why we joined it. POL is a very promising technology from many aspects. Details on real world applications show they (POLs) do what they are claimed to do. They reduce both capital and operating expenses dramatically, sometimes by 50-70%. They save space and energy. In some cases they can even help you recover some installation costs by recycling old copper UTP lines. In a nutshell, they are cheaper, faster, safer, and greener. POLs are more cost-effective solutions to LANs since they use the internationally standardized technology of fiber to the home (FTTH) and with over 100million FTTH subscribers worldwide, the technology is well proven and the cost of the systems has been reduced tremendously by the incredibly large volume of installations.


A-Sk: Wow... Sounds, erm... Too good to be true, frankly. No trade-offs? Cheaper AND faster all-in-one? Environment-friendly, no cholesterol, no GMO, low-calorie?

Jim Hayes: There are a few trade-offs, of course, at least for engineers. For example, you really have to burn some mental calories to learn some new design and installation skills and you may need to upgrade your OTDR fleet. But by now the advantages are way bigger. And yes, they are definitely much more environment-friendly. In an OLAN there are no electronics between the computer room and the user—just fiber, so no heat, no electrical wiring, no grounding, nothing.

A-Sk: Ok, sounds like POL is a thing of the future. If we don't get a piece of that action we risk everything we have. Not now, but ten years from now. Right?

Jim Hayes: I have to correct your estimates. Two years, five years tops. Passive OLANs have already been used for large installations for 3-4 years now. Depending on the market, of course. In fact, I would say this future is already here, it is not just very evenly distributed, as William Gibson once put it.

A-Sk: You mean the technology is already in use at some advanced companies?

Jim Hayes: Exactly. Companies, organizations, facilities. San Diego Central Library, Dubai International Airport, Sandia National Labs in Los Alamos, just to name a few most vivid examples, and we are going to see many more soon, especially in organizations like cities and school systems that have many diverse locations.

A-Sk: So what makes POLs so promising?

Jim Hayes: First of all, the nature of fiber optics and the optical signal traveling. Just think—now in the XXI century copper UTP networks are built by the standards developed around 1990 and based on a 1982 AT&T survey! The data in such networks travel for about 300 ft (100 m). Besides direct cost and related expenses, every piece of this equipment needs special rooms on each floor, 24/7 energy supply, cooling, servicing and maintenance, and all which follows. Now the signal span for a singlemode optic fiber is 15 miles and counting (over 20 km). See how much equipment and related expenses you can eliminate?

A-Sk: So no equipment all along 20km (12 miles)?

Jim Hayes: With a POL, there is nothing between the central computer facility and the user except fiber optic cable and a small passive splitter. Besides delivering the signal, we have to distribute it among users. So yes, there has to be some equipment besides the server, and they are optical mini-switches and optical splitters. But they take a fraction of space and they need a fraction of maintenance as compared to UTP LANs. And those pieces of equipment are passive, so they do not require power and cooling.

A-Sk: A splitter means that the downward signal goes from the server to all computers in that LAN. What about security in this case? Or is it a special kind of splitter-switch?

Jim Hayes: No, nothing special about it, and that is one of the aspects that make the POL relatively cheap. One signal comes in, many copies of that come out. But OLANs are encrypted downstream to keep others on the same splitter from reading your signals, so technically everybody gets it, but only the designated computer can read it. This encryption is another feature which makes POLs more secure. You can get systems that are encrypted upstream also.

A-Sk: And fiber is much harder to tap, isn’t it?

Jim Hayes: Fiber is harder to tap than copper, but as NSA showed, it is not impossible. But again, with fiber you can get systems that monitor for taps, as a countermeasure. 

A-Sk: Can you tell us how passive optical LANs started? They did not just pop out, did they?

Jim Hayes: Optical LANs started with Codenet in the mid-1980s created by a company called Codenoll. It became an IEEE standard (FOIRL first, then 10Base-FX). When structured cabling was standardized, fiber was OK for the backbone, then to the desktop (FTTD) in the form of centralized fiber optic networks. The current generation of POLs based on GPON and EPON FTTH technology started when a telco and a network consulting company teamed up to offer it to large users in the US about 4 years ago. We also have some OLANs using P2P or active Ethernet FTTH components like the system at Dubai airport.

A-Sk: So it has a rather long history. And it is spreading, or rather climbing to the end user, first as the LAN backbone line, then horizontal?

Jim Hayes: Yes, you can say that optic fiber is crawling up closer to the end user, if that is what you mean, although it’s doubtful that you will plug fiber directly into your laptop. But by now the final connection point is an optical network terminal that will usually be a multiport gigabyte Ethernet switch. Looks like a DSL modem, fits on a desktop or under the desk, on the wall, etc, and connects to devices like PCs, wireless APs, and so on, with a regular CAT-5e patchcord. All in all, it means fewer components, and fewer components mean fewer things to fail. POLs are way more reliable. For example, Telco equipment used in POLs is designed to 99.999% uptime, 10 times or more better than most of contemporary commercial LANs.

A-Sk: Jim, thank you for your information. This time we focused more on technical issues, but our users are definitely very much interested in economics of the subject, resources to be invested, and profits to be estimated. This will be the main topic of the second part of the interview. Follow our blog, post your comments, and you will not be disappointed.