Optical fiber pays--all the way to the desktop

Oct. 1, 1999
Facilities personnel in a hospital continually have the challenge of designing and specifying a low-voltage wiring system that meets today's network communications needs, yet has the capacity to meet future needs.Montefiore Medical Center (MMC), New York City, in undertaking a hospital-wide re-engineering project that includes the overhaul of its existing information systems, is trying to meet this

Facilities personnel in a hospital continually have the challenge of designing and specifying a low-voltage wiring system that meets today's network communications needs, yet has the capacity to meet future needs.

Montefiore Medical Center (MMC), New York City, in undertaking a hospital-wide re-engineering project that includes the overhaul of its existing information systems, is trying to meet this challenge.

With its new communications network, using fiber-optic (FO) cable as the media, MMC wants to operate as a seamless health-care delivery system. The hospital already uses a 12-fiber "micro" FO network connecting some buildings at what is called the Moses campus. However, when the project is finished, the main hospital data communications center will connect every site in its network, including doctors offices, affiliated hospitals and ambulatory care centers, thus creating a "macro" network. MMC is taking a practical approach to its network strategy that balances reliability and vision.

Software running on the network will help Montefiore remain a leader in the health-care field. Patient registration, admissions, discharges and the reporting of laboratory and radiology results are logged on the network and processed electronically. In assisting the doctors, for example, the software provides guidelines on whether a test or a drug is the correct one for the patient. All of these protocols dealing with patient care, in turn, help reduce costs by eliminating duplication and reducing paperwork, said Jack Wolf, vice president of management and information Services at Montefiore. With an expected expenditure of $42 million, this communications upgrade project is being done in three phases:

Phase 1. Fast Track deployment of fiber- optic hubs. MMC is installing network "backbones," each of which forms a loop that begins and ends in the network communications center (NCC). Within a loop, selected hubrooms receive six or 12 FO strands terminated in each direction, providing diversely routed redundancy. In critical areas, the hubs use "live" fiber from each direction to provide "hot" standby in case of a failure or a fiber break.

Phase 2. Infrastructure rollout. Three Cat 5 cables serve each desk location - two of the cables are devoted to data circuits and one cable is devoted to a voice/data circuit. Each department's budget - and individual or group needs-determines circuit locations.

Phase 3. Connecting the entire MMC community. The existing FO ring will be connected to adjacent facilities and off-site locations. While Phases 1and 2 are being completed, SONET rings to the affiliated hospitals and outpatient facilities throughout The Bronx will connect the entire network.

SONET (synchronous optical network) is a telecommunications standard that allows data to be transmitted at speeds from 51.84 Megabits/s (the basic rate) to as high as 9.6 Gigabits/sec. Among SONET's features is its support for self-healing rings, which permit a network fault to be circumvented by simply reversing the traffic flow. Survivability is also assisted by drop and repeat, a SONET function that allows signals passed down the network to terminate at one node and then duplicate (repeat) before going to the next and subsequent nodes. In matched node configurations of interconnected rings, drop and repeat allows a signal blocked by a fault to find an alternate path to its destination node.

A second disaster-resistant data center, located 10 miles away in Yonkers, N.Y., has its own standby generator to withstand utility power interruption. At present, this remote data site is served by a FO communications circuit from two different telecommunications carriers, as protection against an accidental cable cut. These FO lines also enter the MMC computer center from two separate paths.

About 16 separate, but interconnected, structures, of various age in about a three-city- block area, make up the Moses campus. The tallest buildings are eight stories high. However, over time, additional buildings have also become part of the hospital complex- including a parking garage and a series of row houses on the east, south and west sides of the campus. Many of these structures are also being wired with both FO cabling and copper voice services.

FO cabling network The FO ring topology network, connecting the buildings to the NCC, or main computer room, is installed in incremental steps, as departmental funds are released. E-J Communication Systems, a division of E-J Electric Installation Co., Long Island City, N.Y., is doing the work, under the direction of project managers Gerry Curreri and Steven Caltabiano.

The primary feeder runs (backbones) from the NCC are fiber-optic cables with 96, 60, 48 or 24 strands of multimode fiber, depending on the capacity needs of each building. Due to the layout of the numerous structures behind the main hospital, a star topology is used, feeding from collapse points located in the building (in that cluster) closest to the main hospital. At that point, the fiber is either fed from a 100BASE FL switch or directly tied to the fiber switch in the NCC via patch cords.

Since network administration occurs mostly at the NCC, E-J Communications made hundreds of fusion splices at strategic transition locations to minimize and simplify hub deployment time.

The cables and administrative hardware consist of:

Riser cables run vertically through the building core, terminating at designated administrative distribution closets. Eventually they are routed back to the originating point to provide redundancy.

Horizontal FO cables (plenum-rated) provide connectivity to some previously existing hubs or departmental "micro" networks.

Work area cables, called the horizontal link, are typically four pair, Cat 5, unshielded-twisted pair (UTP) copper cables run from the work area wallplate back to patch panels in the hub room. In work area locations that are too far away from a communications closet to assure top performance by the UTP cable, FO cable is used. These cases are rare, because a lot of time was devoted to selecting hubroom locations.

Installation constraints One of the most challenging aspects of the project was gaining closet space (which had to be relinquished by individual departments) for the new telecommunication closets. Since a straight riser path often was not possible, conduit bends, transition hardware and different mounting hardware are used to support the FO cable. The communications closets, or in some cases, lockable cabinets, hold the racks, patch panels, electronic hubs and conversion equipment along with the UPS.

In addition, much of the installation work had to be done during off-hours- nights and weekends. In areas that never close, like the emergency rooms, cleanliness and safety during installation was very important.

As is typical in the telecommunications industry today, the installation complies with the latest TIA/EIA standard regarding cabling, such as complying with the bend radius and distance limitations. MMC is standardizing on the products of a major cable manufacturer and on the use of Type SC connectors. The 568SC duplex connector, is the recognized standard fiber-optic interface at the wall outlet in premises application. Defined in the TIA/EIA 568A Commercial Building Telecommunications Standard, the SC connector offers power coupling efficiency and repeatability in disconnecting and repositioning the connector.

At the completion of the FO installation, each fiber was tested in accord with TIA/EIA 526-14, Optical Power Loss Measurements on Installed Multimode Fiber Plant using Power Meters.

The engineering telecom/network design team for MMC includes Brian Hoch, Jim Fiorato, and Phil Munvez.

About the Author

Joseph R. Knisley

Voice your opinion!

To join the conversation, and become an exclusive member of EC&M, create an account today!

Sponsored Recommendations

Electrical Conduit Comparison Chart

CHAMPION FIBERGLASS electrical conduit is a lightweight, durable option that provides lasting savings when compared to other materials. Compare electrical conduit types including...

Fiberglass Electrical Conduit Chemical Resistance Chart

This information is provided solely as a guide since it is impossible to anticipate all individual site conditions. For specific applications which are not covered in this guide...

Considerations for Direct Burial Conduit

Installation type plays a key role in the type of conduit selected for electrical systems in industrial construction projects. Above ground, below ground, direct buried, encased...

How to Calculate Labor Costs

Most important to accurately estimating labor costs is knowing the approximate hours required for project completion. Learn how to calculate electrical labor cost.