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A Heads Up

Headends
Adding fiber to the homes of a development starts with adding a house for that technology We asked experts how to build one
by Tom LeBlanc
Although sizes of AFLs headends vary based on the number of units in its developments, director of access solutions Kent Brown estimates about 200 square feet for a 300- to 500-home community

evelopers that want to provide their homebuyers with sexy fiberoptic benefits — like triple-play

TV, phone and high-speed Internet services — must first provide a very non-sexy hub for that infrastructure Usually called a headend, although sometimes called a central office, the hub hosts the electrical components necessary to process and encode the video, data and voice streams entering the development The electronics within the headend, in turn, distribute the information throughout the development Sounds simple, but since fiber-to-the-home FTTH technology is a relatively new concept, how to build a headend isnt exactly common knowledge We talked to some of the few folks with extensive headend building experience and asked them what developers need to know
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Bob Saylor, CEO of Sky Cable Inc, is a consultant and content
provider working in conjunction with a company that designs and installs FTTH networks Kent Brown is director of access solutions at AFL Telecommunications, a provider of fiber-optic products, engineering expertise and integrated services to the telecommunications industry Ben Wright is director of FTTH design engineering for Connexion Technologies, a company that designs, installs and operates fiber optic networks for developers And Diane Kruse is the CEO and founder of Zoomy Communications, a design, engineering, consulting and construction company for FTTH implementations These folks

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Defining the Fiber Architecture
There are two basic types of fiber deployment topologies: I Point to Point is a configuration in which there is a dedicated fiber for each subscriber It can be tailored to allow higher bandwidth to an individual home, but can be more expensive because more fiber must be laid No pedestals, handholds and in-ground faults are needed
I Passive Optical Network PON defines

With a growing number of developments going up in hurricane country, Connexion Technologies headends need to be hurricane proof to protect the valuable equipment
inside, according to Ben Wright He says the company usually builds them with concrete blocks or 8-inch poured concrete walls It also likes to match the exterior to the development so it doesnt stand out too much In this case, it used stamped brick

an architecture in which the fiber passes through active switches that each split the bandwidth signal by 32 This type of architecture is less expensive to deploy because it reduces the costs for devices and subscriber interfaces However, it can be a limiting factor for HDTV and other high-bandwidth applications –Jason Knott

have offered to TecHome Builder readers some of the basics of building a headend Its important to note, they all say, that each development and each FTTH deployment is different Nevertheless, based on their experiences, the experts offer insightful advice

Sizing It Up
The wide range of size suggestions from our expert panel — from 100 to 480 square feet — is reflective of there not being an established formula for building a headend The size also varies due to the scale of the development — a critical determining factor, according to Kruse For instance, when working on a 3,000-unit project, she says Zoomys
typical headend buildings range from 300 to 400 square feet Brown agrees that it varies greatly based on the size of the development, but offers a generic answer of 200 square feet for a 300 to 500 home community Saylor recommends a smaller scale of 100 to 300 square feet Wright, meanwhile, says Connexions buildings are 21 feet by 25 feet, or 480 square feet inside to work with Brown points out another variable: Some folks use the headend to help market technology aspects of the community, so they include a sales lobby, rest room and other work space

Raiding the Headend
We know that this hub of technology hosts the components necessary to process and encode the video, voice and data streams entering the development To explain what that physically entails,

however, Brown runs down the list: Video — Typically, this equipment is the largest part of the headend For RF video, equipment would include receivers, modulators, satellite uplinks and digital headend equipment, but exact configuration can vary widely You are looking at six to eight racks of equipment for a full service headend with 80 channels for basic services and full 250-plus channel digital A basic video headend could
be one to two racks Voice — This includes the voice handoff from the local provider ILEC [incumbent local exchange carrier], CLEC [competitive local exchange carrier], VoIP [voice over Internet protocol] It would typically include a gateway and other service provider equipment In some cases, the voice equipment will include a community IP PBX [private branch exchange] to support local call routing and advanced features The voice services would then be routed into the community network PON or point to point, see sidebar on page 41 The community network equipment will consist of a core router, aggregation switches and/or equipment chassis It will likely be a half to one rack for voice equipment and one to three racks for community network equipment Data — This includes the data handoff from a local provider Data services can include a wide variety of things, like Internet access, security services/monitoring, etc Data services are then routed into the community network A half rack is likely needed for data handoff equipment Brown also adds a few external items to the list, including satellite dishes between one and

seven dishes per headend, with diameters of between 1 and 5
meters, a generator although some use DC power equipment and have batteries and HVAC

Straw, Wood or Brick?
Typical building architecture can be used to build a headend, according to Saylor The caveat, of course, is that it depends on what a particular developers typical building architecture is The headend needs to be sturdy and elementproof Zoomy prefers prefab concrete buildings or poured-in-place concrete structures, according to Kruse She adds that having a concrete structure protects from flooding, high winds, tornados, fire and such Connexion has many properties in Florida and around the Gulf of Mexico — hurricane country In an effort to provide more stability against bad weather, Wright says the company typically builds headends with concrete blocks or 8-inch poured concrete walls so they are solid vaults He adds that Connexion takes it a step further We try to match the exterior of the headend building with the development so it doesnt stick out as an eye sore We have buildings with stucco finishes, stamped brick, Hardie plank, rock columns and even some fake doors and windows

Location, Location, Location
Headends can go anywhere In a way, the location is
inconsequential, explains Saylor Fiber can transport signal for miles before appreciable signal loss is experienced There are locations, however,

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CONNECTED COMMUNITIES FTTH DEVELOPMENTS

that are more advantageous than others To minimize the cost of the design and length of cables to be run, a centralized location is preferred However, not all developments have a central location, per se, because many are sprawled out The headend doesnt even have to be on the developments property eg, a headend in one development could also serve another of the builders nearby developments The potential problem in that case — and in the case of sprawled out developments in which city roads or state highways run through — is that laws vary from town to town In some jurisdictions, for example, significant fees are required to run cable under or over public roads These limitations have been an issue for Connexion, according to Wright We build on every property we provide infrastructure to because we are a private company and not a service provider, he says We cant transport video content across public [roads], so we stay on the private property in the
neighborhood As for central locations, Wright says Connexion simply works with the developer to pick a location that works for both parties Sometimes they have to compromise because the developer wants to hide the headend, but we need to have a clear path to the southern, eastern and western skies for satellite dishes to pull down video content He adds that its good to be close to the entrance facilitys fiber, which connects back to outside world The closer we are, the shorter and cheaper the path to get the fiber connection into the building

The trick is to create enough room for the equipment and enough room for technicians to maneuver In Connexion Technologies case, the headends are 21 feet by 25 feet, providing a 480square-foot space

Keeping a Cool Headend
Logic dictates that a room full of constantly running technology needs to be kept cool to avoid overheating In fact, says Brown, cooling is the biggest issue He explains that calculating heat load, which varies with equipment type, and cooling requirements are key and affect performance — not to mention the comfort of technicians The building experts we spoke to keep headend temperatures between 69 and 72 degrees To do
that, Wright says Connexion uses two 2-ton A/C units that work on a rotating basis so theyre not running at the same time

IPTV Is a Headend Shrinker
The equipment required to support video is typically the most complex and expensive portion of a FTTH headend — often requiring eight racks of equipment, extensive configuration effort and specialized equipment to support the merging of RF video signals onto the fiber network None of these issues are showstoppers, but the overall cost and technical complexity can leave even the experts scratching their heads One satellite TV provider hopes to solve both fiber-to-the-home FTTH issues by way of an IPTV Internet protocol TV solution The company is expected to launch an IPTV system this summer, designed to deliver IPTV in a box The solutions equipment occupies less than one rack and delivers the companys full scope of programming, including high definition I see the emergence of IPTV technology paired with FTTH to be the most significant technical transformation benefiting private cable systems since the original master antenna TV, says Bob Saylor, CEO of Sky Cable Inc The IPTV solution could make FTTH more accessible and drive value
from the headend to the living room –Kent Brown Kent Brown is director of access solutions at AFL, a provider of fiber-optic products, engineering expertise and integrated services

Multi-Dwelling Equals Multi-Headends Putting a Price on It
Calculating costs of building a headend is inexact, since just about every factor is variable For instance, there arent a lot of developments that have the exact same number of units Nevertheless, we asked our panel to answer the question of headend cost We typically pay around 80,000 for each headend building we build and that doesnt include equipment, Wright says The size of the community doesnt matter because we try to provide the same services at all of our sites He points out that since the size of the community doesnt change the 80,000 figure, its beneficial for Connexion to work on larger communities It will work on the smaller ones, but tends to keep above 250 lots, he explains In Zoomys evaluation, it does factor in the price of equipment It cites the cost of constructing a headend for 500 units at between 190,000 and 240,000 When working on multi-dwelling units MDUs, the entire headend approach can change The reason, Brown says, is
that many MDUs are built with equipment rooms which can accommodate the technology that in a sprawled development would have to live in a headend Also, MDUs provide the ability to design systems that are distributed between a main distribution frame MDF and intermediate distribution frame IDF, he adds This means that typical headend components can split among several locations This can reduce cost per door

Cashing In on Headends
The return on investment varies on a case by case basis, says Kruse Determining factors include the number of lots passed, the time it takes to sell those lots, whether the developer intends to bundle the triple-play fees with the association dues and how the developer pays for infrastructure construction THB

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