Army's Optical Tryout

An infrastructure modernization project slated for completion this fall at the Army Network Enterprise Technology Command (NETCOM) headquarters building at Fort Huachuca, Ariz., could play an important role in determining the Army’s future use of Gigabit Passive Optical Network (GPON) technology.

Originally used in the consumer market for delivering phone, Internet and video services to the home, GPON is a local area network technology that has drawn increased military interest by providing increased bandwidth along with cuts in capital, power and other costs.

Passive optical networks are a point-to-multipoint access mechanism that relies on unpowered splitters to give one fiber the ability to serve multiple users. GPON is an International Telecommunication Union standard that provides increased total bandwidth and bandwidth efficiency by using larger, variable-length packets. (See “Optical Networking Shines,” MIT, March 2013.)

Replacement of the Fort Huachuca facility’s existing copper wire infrastructure with fiber-optic cabling, as well as all of the active network switches with GPON solutions, should be finished by mid-October, Army officials say, with users migrating to it over the next two months. Once completed, they add, the success of the installation will be viewed as a proof of concept for the technology within the Army.

Ways to Save

The Army’s goal with this and other new processes, procedures and technologies has been to increase efficiencies, while reducing costs and maintaining support to warfighters, according to a NETCOM spokesman. In addition to boosting capabilities and flexibility of service, GPON advocates see substantial cost savings.

A GPON infrastructure is centrally managed, requiring fewer man-hours to maintain than active/distributed environments, and provides the ability to secure and monitor services from a centralized location. The equipment footprint is substantially smaller than a switch-based inventory, resulting in efficiencies in space, energy utilization and human resources to support the infrastructure. Passive optical network devices also have an expected life cycle of eight to 10 years or higher, compared with approximately five years for traditional copper management devices.

GPON systems can reduce space requirements by 90 percent, energy consumption by 80 percent and total cost of ownership by 70 percent, according to an estimate by GPON systems provider Tellabs.

The Fort Huachuca project is being overseen by the U.S. Army Information Systems Engineering Command, and their systems integration contractor is NCI. In a recent interview, Randy Devine, senior vice president of operations at the company’s Sierra Vista, Ariz., office, offered a look at some of the benefits and challenges of the project, including the deceptively simple but significant advantage of reducing the number of equipment closets.

“In the project we’re doing on Fort Huachuca, they are reducing from 29 telecommunications closets with active network switches down to three,” Devine explained. “Today, if you open one of those 29 closets, there is a network switch that serves as the interface for all users in the area. Those switches will be replaced with a passive fiber-optic splitter, which ties back to a single closet on each floor.

“So you’ve eliminated the primary component that can break, requires maintenance and quickly becomes obsolete, with a piece of glass that has none of those disadvantages. It also eliminates the power and cooling requirements for that closet, which is why GPON is considered a green technology,” he added.

The headquarters building, Greely Hall, is over a half-century old, Devine noted. “The communications closets are literally closets, only about three feet deep, because they were designed with only telephones in mind, as opposed to housing today’s active network switch components.

“In an older building like Greely Hall, the passive fiber-optic components used to support a GPON solution solve a lot of space problems,” Devine said, while adding that the benefits in a new building could be even greater. “You can eliminate the need for 90 percent of the walk-in telecommunications rooms, as well as all the power, air conditioning and switch maintenance that goes along with them. The Army is interested in GPON because of all those potential savings.”

Security Issues

Another major benefit concerns security and the practical issues involved in servicing individual workstations, especially in a building like NETCOM headquarters, where there are areas of classified users amid a less sensitive environment.

“With the current technology, to have a primarily unclassified building with a pocket of SIPRNet users who need classified access, you have to run a protected distribution system (PDS). A PDS is a grid of rigid conduit pipes and metal junction boxes that run over and into individual cubicles to protect the classified cable,” Devine said. “The security policy is that the PDS has to be visible and inspected daily, requiring someone to walk through the area and see that no one has tried to tamper with it. You can’t put it above the ceiling because someone could theoretically penetrate it without anyone knowing.

“Another option is to put an encryption device at the desk, which becomes cost-prohibitive and requires labor-intensive management of the encryption keys,” he added.

With fiber as the medium for GPON, however, it is possible to use spare fibers for security alarms to protect the fiber cable from tampering. “For our project, we are implementing a secure passive optical network solution using the spare fibers and a third party vendor to augment the GPON with alarm management software,” Devine said.

“The solution includes an armored shield encasing the fibers,” he explained. “Using the spare fiber strands inside the shielded cable monitored by the alarm management appliances and software, the technology detects any movement, such as an individual trying to tap into the cable, and sets off an alarm that can be monitored remotely. You can set the system for different sensitivities, where the alarm would be triggered upon a single touch or only after an intensive intrusion attempt of several seconds.”

Because the armored cable is flexible, it’s easier to install than traditional PDS, and because it is alarmed, it can be run above the ceiling tiles like unclassified cable, because it doesn’t have to be visible. “In that one multi-strand armored fiber cable, you have strands dedicated to the alarm system, NIPRNet users and SIPRNet users. In theory, you could also add coalition or other classified levels as well,” he said.

NCI’s other GPON projects with the military include maintaining a GPON environment at Andrews Air Force Base, Md., for the Air National Guard. ♦

Last modified on Wednesday, 22 January 2014 16:16

Additional Info

  • Issue: 7
  • Volume: 17
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