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Issue 7: Current Developments - Video Tele-Conference

GCI Communications High Resolution Video Teleconferencing and Internet Access

A VIASAT Customer Case Study

Download the full paper in PDF (252 KB)


Just say the name "Alaska" and it conjures images of snow and wilderness. Though not all of the state is like that, most of it is, with sparse population and temperature extremes reaching to -60°F. The state features only three main centers of population, yet there are many people, living in villages in the wilderness areas, who want to be connected to modern schools, health care facilities, and long distance phone service.

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Since 1982, GCI has been finding ways to provide those connections in Alaska. The company has grown to about 1,000 employees today, providing cable television and PCS wireless service in addition to satellite communications.

GCI's challenge is reaching remote regional centers, then connecting those sites with even more remote rural villages. Regional centers are typically located near coastal river deltas. These centers include school district offices, cultural centers, and the Regional Health Corporation, including doctors' offices and a hospital. One such center is the Native Village of Kotzebue. Originally called Qikiktagruk by the native Iñupiats, Kotzebue is the hub of the 11-village Norwest Arctic Borough. About 7,600 people live in the area that covers about 36,000 square miles (93,000 sq km).

Located in northwest Alaska, 30 miles above the Arctic Circle on the Baldwin Peninsula, the area is bordered on one side by Kobuk Lake. The other side of the Peninsula, the side that the community where Kotzebue proper is located, borders the Chukchi Sea by way of Kotzebue Sound. Other major features of the area include the deltas of three large rivers, the Kobuk, Noatak, and Selawik, and mountain ranges on the mainland across from the peninsula collectively referred to as the Brooks Range, or the original names of Minumirauq and Qipaluq. There are no permanent roads to the rest of Alaska, or even to other villages in the borough, so transportation is by air.

"We're using more than 150 ViaSat LINKWAY 2100 VSATs for distance learning, telemedicine, and Internet return channels for these remote areas," said Andrew Rzeszut of GCI. LINKWAY is a hubless VSAT system that enables cost-effective integration of a variety of applications into one network in mesh, star, or multi-star hybrid topologies. Adaptive on-demand bandwidth and advanced coding engineered into LINKWAY provide broadband connections efficiently and cost-effectively. Customers save transponder costs and connect seamlessly to networking applications using IP, ATM, Frame Relay, and ISDN protocols. All terminals are interoperable over C- or Ku-band fixed satellite services (FSS) satellites with fixed-beam, split-beam or cross-strapped configurations.

The LINKWAY 2100 provides the following for the GCI network:

  • Protocols: IP Packet transport over Frame Relay serial interface using RFC-1490
  • Bandwidth on demand on 5 Msps carriers
  • IP multicasting
  • Configurable Quality of Service
  • Multiple carriers and transponders
  • H.323 IP VTC equipment

In the Kotzebue example, the distance learning application reaches 11 remote villages. Remote villages are using the communications to draw on the resources of the regional centers, which in turn are connected to the more populated cities of Juneau, Anchorage and Fairbanks. Though remote villages may have a few teachers, most likely they are not skilled in all subjects. Using the LINKWAY network, teachers located in Kotzebue who have specific expertise can reach out to more sparsely populated areas. Staff meetings and teacher training are other applications of the education portion of the network. GCI uses H.323 video conferencing equipment running at a rate of 384 kbps in both directions(combined voice and data rate) to deliver its distance learning services.

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The telemedicine network includes email, database access for patient records, Web access, file transfer. VoIP, and a videoconferencing network. Doctors can consult with their patients "face-to-face," educate them on treatments and healthcare, and complete administrative tasks as well.

"In fact, some medical procedures have been conducted remotely via video teleconferencing between Kotzebue and the remote villages in the region," said Rzeszut. "One specific instance involved a child who suffered a facial injury in a 4-wheel ATV accident. Because it was after dark when the accident occurred, and the runway in the village wasn't lighted, the child couldn't be transported to Kotzebue until the following morning." Doctors in Kotzebue guided the medical clinician in this remote village through a procedure to stitch the child's cheek. The following day, the child was transported to Kotzebue for further medical treatment.

Prior to the more recent installation of LINKWAY, GCI selected ViaSat Skylinx VSATs to provide long distance phone service and private line voice throughout Alaska. Like LINKWAY, Skylinx provides full mesh connections, making it ideal for direct, single satellite hop connections between any two locations. Skylinx uses Single-Channel-per-Carrier (SCPC) and Demand Assigned Multiple Access (DAMA) technology, setting up calls as they are initiated, just like a terrestrial network circuit switch. DAMA networks can share a much smaller amount of satellite bandwidth than networks using dedicated circuits, taking advantage of the random and occasional nature of telephony traffic. The Skylinx network includes 139 remote sites.

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Remote installations are typically an antenna, along with a small, climate controlled building housing the RF, transmit, and receive equipment. Gateway locations for tapping into Internet backbones or the terrestrial phone network use 13-meter antennas. Regional centers typically use 9-meter dishes, while remote villages use 3.6-meter reflectors. GCI services use C- and Ku-band transponders aboard the Galaxy 10R satellite. The networks are controlled from redundant, geographically diverse network management interfaces located in Anchorage and Issequah, WA. 3

For the future, GCI is going to be expanding its networks and look for ways to improve the bandwidth efficiency. Implemented already in the ViaSat ArcLight VSAT system, ViaSat-exclusive Paired Carrier Multiple Access (PCMA) combines both transmit and receive signals into the same bandwidth, to as much as double bandwidth capacity (or cut bandwidth use by half).

"One option that GCI is very interested in is looking at PCMA technology as a way to save satellite bandwidth for the fixed-assigned SCPC carriers in our network," said Rzeszut. "The PCMA 'hub canceller' may have possibilities if it could be offered as a stand-alone product."

Comsat Labs and Comsat Laboratories are tradenames of ViaSat Inc. Neither Comsat Labs nor Comsat Laboratories is affiliated with COMSAT Corporation. "Comsat" is a registered trademark of COMSAT Corporation.


ViaSat Inc.: http://www.viasat.com/

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