DESIGN: Gateways and TCs in the age of multiple service providers

A good gateway and collocate room help control how telecom services enter your property.

Feb 1st, 2000
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Jerri L. Harter / Intermedia Communications Inc.

For years now, telecommunications service providers have been offering users a burgeoning number of services, which is a reflection of a rapidly growing economy. Since most customers want to stay current with technology but are not experts in voice, video, or data, they may not know enough about their needs to get what they want or what they may have paid for. The result can be messy installations, full wiring closets, conduits and sleeves either full or misused, ceilings full of abandoned cable, poorly designed end-to-end solutions, dissatisfied customers, and upset building owners or property managers.

To confuse the issue, buzzwords are thrown around, and people want the latest technology but don't always know why. Many property owners want to be able to say they have current technologies such as Synchronous Optical Network (SONET), Asynchronous Transfer Mode (ATM), and digital subscriber line (xDSL) even if they do not have an immediate need for such technology. It's an attractive proposition to tell potential tenants the technology is in place. Clients sometimes tell network-infrastructure designers that they want fiber optics but usually can't explain why.

For new buildings or complexes, the pathways and infrastructure designs are most crucial. Architects, builders, developers, planners, and property-management firms should seek the services of registered designers who are best-qualified to design such infrastructures. It is very important that an adequate number of duct banks, vaults, and diversified routes be planned into a new development or park. To enable a facility to be technology-ready, the designer should plan redundant conduit paths, ample ducts into the building, and entrance points into the complex or building.

First things first

A smart infrastructure or pathway design is the most important prerequisite before any kind of media or technology upgrade can be delivered. For example, the first step may be to enter the complex through two different entrance points. Plan for the possibility of being served by multiple providers. In other words, place a point of entrance, such as a versatile crossconnect box, at the spot where competitive local-exchange carriers (CLECs) and multiple system operators (MSOs) would enter the property. This method controls service ingress without limiting anyone. From this point, service providers may like the option of having two separate pathways into the equipment room (for redundancy). These pathways need to be some distance from each other to limit the possibility of their both being cut at the same time. It may be wise, depending on the layout of the campus or environment, to install a cable vault somewhere outside of the headend or main equipment room. This practice allows for flexibility and future growth without radically changing the entrance facilities.

Providing a crossconnect where multiple system operators enter the client's property controls ingress without limiting services.
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Once the main equipment room has been identified, the duct bank serving the rest of the complex must be engineered. Depending on the potential occupancy for the property, some assumptions can be made. For example, when sizing up riser requirements, BICSI (Tampa, FL) calculates 100 usable square feet for every workstation. However, my experience shows that 200 to 250 sq ft per workstation is a realistic estimate of a building under construction because of the nonusable space in every building. So based upon total square footages, one can assume a minimum requirement for each building and calculate upfront for some growth. In addition to basic voice and traditional analog services, you can bet that fiber optics may well serve many customer data requirements. Depending on the transport mechanism, enterprise arrangements, and other equipment criteria, both multimode and singlemode fiber may be installed. Of course, no one can accurately estimate the exact number of fibers needed; however, a qualified registered engineer can design a very close configuration.

Equipment rooms and TCs

Once the pathways are established, plan equipment rooms, telecommunications closets (TCs), and ducts into each building. After the building is erected, it's usually too late to install additional 4-inch conduits from the outside; it can be done, but it's not easy. Many smart builders are placing additional conduits into buildings and leaving them capped off for later use.

Architects may fail to plan adequate room for TCs because property owners and managers want to limit the spaces that cannot be leased. It's easy to understand their concerns because space that is not leased will produce no revenue. But there's a bigger issue brewing here: It's not just a TC any more. What about all this talk about convergence? As technology advances, disparate systems comes together; not just data and voice, but building-management, security, and life-safety systems will all be networked.

As various applications converge, equipment rooms and TCs become more important. As service providers install their equipment and cabling contractors install cabling, the cores or sleeves get choked, and the wall space is not used effectively. This problem is compounded if space was constricted to begin with. Therefore, in addition to basic TCs, a separate equipment or collocate room should be planned for service providers' equipment. Properly managed, there can be enough space to keep everyone's equipment orderly and well-managed. Depending on whether a multistory building or multiple buildings are involved, this collocate room may be located in one strategic building or in each building.

A collocate room can be designed so that owners can lease smartly laid-out space. If a well-planned space is provided upfront-a space that allows maximum usage of pathways and minimizes wasted space-MSOs can use all the space provided, and building owners can get the most from each service provider. This approach makes it easy for providers to set up their services. It also allows the owner to gain the most revenue from the building by offering tenants a complete set of services. Because property owners or managers often are not telecommunications-savvy, it is recommended that an experienced, well-qualified service provider manage all of these processes.

How does a building owner benefit from these considerations? Let's look at a scenario that can be beneficial to all parties, including the customer. Controlled access to the building or complex can be done a couple of ways. Install a crossconnect system with fiber and copper facilities back to a main collocate room. In addition to these facilities, place adequate spare duct banks for future or leased pathways. Control some of these spare pathways by installing multiple innerducts within them, thus preventing the underutilization of these conduits after one cable is installed. For ease of maintenance and additional fiber installations, each service provider's innerduct should be a different color so service providers can easily identify their own innerduct.

Copper and fiber facilities can also be installed throughout the campus so service providers can choose to lease these facilities as well. Carrier-based equipment could be installed so that an owner or service provider can act as a bandwidth manager and allow others to hop on the information superhighway.

Managing bandwidth

Many of the large carriers are installing SONET rings around the larger metropolitan areas. This carrier network is designed to carry large volumes of data. Now, customers want to know that they have access to SONET rings if needed. As an inducement for tenants to move into their office buildings, property owners are looking into installing a SONET ring within the complex or office park. This can be an expensive proposition, however, since baseline costs per building can exceed $50,000 each. In addition, further design criteria must be considered, such as the type of backbone the SONET ring will connect to (e.g., ATM, Fiber Distributed Data Interface, Fast Ethernet, or some other type). Routers, gateways, and specific connectivity issues must be addressed. A critical issue is determining where to draw the line between the connection to the carrier's SONET ring and the customer's local area network. Understanding where this point lies will save money because it will reduce the time the service provider will spend troubleshooting the end user's problems.

Once these issues are ironed out, the game begins. The service provider becomes the bandwidth manager and can charge appropriately. Of course, the bigger the client, the greater the demand for bandwidth-and if the client has multiple locations within the complex, the need is even greater. Rarely do customers downsize their need for bandwidth.

The best thing a service provider can do is design a scalable network with plenty of headroom. Since SONET rings are scalable, the service provider can grow the ring as demand presents itself. A SONET ring can start out at OC-1 or OC-3 rates and can be grown to OC-192 or OC-256 if needed. An OC is equivalent to 51.84 million bits per second. At an OC-256 level, the capacity would be there to accommodate 172,032 voice circuits. These types of networks are usually applicable to large interexchange carriers, but the local service provider doesn't have to install a terribly oversized ring.

What if the customers or other competing service providers don't want to use your SONET ring? If you planned your infrastructure correctly, that's not a problem either. The next best thing to leasing bandwidth is in-place fiber or copper facilities. After the landscaping is done and the grass has grown back, having vendor after vendor dig up your property and bury cable is not a popular option. Also, it's more costly for a vendor to do this at this stage. So if the price is right, a customer or service provider may choose to lease fibers or pairs of copper from you.

If they don't think this is a good idea, you can lease duct space to them by the foot. That's right: the spare 4-inch conduit you put in the ground right after finish grade. If 4-inch conduit is not managed properly, however, it can become impossible to add more cable after the initial installation. The answer is simple: Install as many innerducts in the spare conduits as possible. You may want to leave a couple of ducts for copper cable installation later. If customers are determined to install their own facilities, they can. The time and money they save using your installed ductwork is worth a small monthly rental fee to use them.

The most important decision any architect, owner, developer, or manager can make is to involve a qualified design engineer upfront before construction is completed. So often, equipment rooms and TCs are undersized. In addition, many people don't plan for the future-they think about today and the minimum cost the project can be done for. Unfortunately, such shortsightedness usually results in a premium to be paid later.

The need for technology will continue to grow. Along with that trend, equipment convergence will also continue-this means centralization of equipment and common structured cabling systems. All these systems need to be terminated somewhere. Why not do it right? Once the facilities are in place, all future technologies will be available to the tenants when needed.

Jerri L. Harter is operations manager at Intermedia Communications Inc. (Carmel, IN). He can be contacted at (317) 573-6068 or


Revenue Streams for Designers

  • Provide a vehicle for entry into the complex or building.
  • Provide necessary bandwidth by installing SONET throughout the buildings served.
  • Lease in-place copper or fiber facilities.
  • Lease controlled spare pathways.
  • Provide traditional voice services by installing a switch or access to one.
  • Provide direct Internet access.
  • Provide other unique product or consultative offerings that others don't think of. Remember that customers are often not knowledgeable about technology offerings, so they might not know what you have to offer unless you spell it out for them.

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