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International data networks.


Advances in satellites and fiber optic technologies are helping international data services keep pace with the demands of an increasingly global marketplace.

Fiber optic (or lightwave) undersea cables already span the Atlantic and Pacific Oceans, and more are planned for the 1990s in anticipation of a united Europe and greater trade with the Pacific Rim countries.

The fiber optic era began two years ago with the inauguration of the 560-Mb/s Trans-Atlantic Telecommunications 8 (TAT-8) cable, which uses two working pairs of optical fibers, with one pair branching off to the U.K. and the other to France. It has since been joined by the Hawaii 4/Trans Pacific Cable 3 (Haw-4/TPC-3), which stretches from California to Guam and Japan via Hawaii. In Japan, the Cable system links with the H-J-K cable system, connecting Japan with Hong Kong and Korea.

Next fall will see the cut-over of TAT-9 with two 560-Mb/s channels, with a TPC-4 providing the same capacity between the U.S. and Japan by 1992. A submerged multiplex branching repeater will allow TAT-9 to come ashore at five different points on both sides of the Atlantic--in the U.S., Canada, U.K., France, and Spain. The Spanish landing site will play a crucial role in interconnecting TAT-9 with two fiber optic cable systems planned for the Mediterranean.

Those two systems--in the eastern and western parts of the sea--will eventually link Spain with Italy, Greece, Turkey, Israel, and other major countries in the part of the world.

Last October, AT&T won the contract to install Hawaii-5 (Haw-5), an undersea fiber optic cable running from the U.S. mainland to Hawaii. It's scheduled to be cut over in 1993. Haw-5, which is jointly owned by 23 carriers, will have two active and one backup fiber pair supporting speeds of 560 Mb/s per fiber pair. Haw-5 will connect with the Pacific Rim East (PacrimE) fiber optic cable, which will run from Hawaii to New Zealand. It is also slated to be cut over in 1993.

PacrimE, in turn, will link with Tasman-2, a fiber optic cable that will run from New Zealand to Australia, creating the first fiber optic route between the U.S. and Australia.

Looking further out, AT&T and the other cable owners are considering a TAT-10 and TAT-11 in the mid- and late 1990s, and TPC-5 around 1996.

In anticipation of the new trans-Pacific cables, AT&T and Kokusai Denshin Denwa (KDD) of Japan have been conducting feasibility studies with optical amplifier technology operating at 2.4 Gb/s, or eight times the capacity of present fiber optic cables.

Todays's cables use electronic repeaters that convert light pulses, or photons, to electrons and back every 40 to 60 miles. With optical amplifiers, there is no need to convert the light pulses to electrons and then back into light> the signal get a boost as they pass through spliced-in segments of fiber containing the rare earth element erbium. The optcial amplifiers are pumped by semiconductor lasers that energize the signals as they pass through the fiber.

Also, unlike electronic repeaters, which have to be replaced if the bit rate or modulation is changed, optical amplifiers can handle varying system configurations. TPC-5 is expected to be the first cable system to use the new optical amplifiers.

Private, Fiber Cable

Meanwhile, US Sprint and Cable and Wireless of the U.K. have installed the first private owned trans-Atlantic fiber optic cable, PTAT-1, linking London and New York with a capacity of 80,000 simultaneous calls. Cable and Wireless has also teamed up with Pacific Telecom Cable Inc. of Vancouver, Wash., on the 1260-Mb/s North Pacific Cable (NPC), which is scheduled to be cut over this month.

In marketing fiber capacity, NPC's developers are inviting users to become part owners of the facility. Users can buy 6-Mb/s chunks of NPC at a cost reportedly 50-60% below that of leasing equivalent satellite facilities, based on service over the 25-year expected life span of the fiber link.

Besides providing a fiber backup to Haw-4/TPC-3, NPC is expected to reduce the cost of trans-Pacific communications by giving users an alternative service. Currently, dedicated circuits over Haw-4/TPC-3 cost more than equivalent satellite facilities.

Once NPC is cut over, however, the price of fiber circuits is expected to decline, so that by 1992, when TPC-4 comes on stream, the cost of dedicated trans-Pacific fiber circuits should be equal to or less than the cost of equivalent satellite facilities--duplicating the situation that already exists with service between the U.S. and Europe.

Role For Satellites

Despite the promise of fiber cables, many observes still see a crucial role for satellites, which offer global accessibility, greater flexibility, and more options than the point-to-point services of cable systems.

Satellites have the advantage of providing point-to-multipoint transmissions and going to many places where cable will not go. Also, satellites have an impressive record of reliability unmatched by undersea cable and terrestrial networks.

AT&T uses a combination of satellite and cable circuits for its international services. It uses TAT-8 to provide fulltime digital private-line links between the U.S. and U.K. and France, operating at 56 and 64 kb/s and at 1.5 and 2.048 Mb/s. Known as International Accunet Digital Services, the offerings give users a choice of a monthly price plan or fixed terms of three- and five-year duration.

AT&T's International Accunet Reserved 1.5 Service uses international satellite circuits leased from Comsat to provide a digital two-way 1.5-Mb/s service between the U.S. and Canada and a number of European countries for data and videoconferencing uses on a reservations basis.

AT&T has also extended two other international services to several European locations: Skynet International Service employs either shared AT&T or customer-premises earth station for service at rates of 56 kb/s and 1.5 Mb/s using Intelsat satellites. And International Dataphone Digital Service provides 56-kb/s transmission over trans-Atlantic cable systems.

At the TCA show in San Diego last September, AT&T announced plans to extend its Global Software Defined Network (GSDN) service to more than a dozen new countries during the next two years. AT&T said it will extend GSDN into Belgium, Canada, France, and Japan by the end of next year, adding to the existing links to Australia and the U.K.

GSDN, which is priced 50-60% below standard AT&T long-distance rates, is a cost-effective international calling alternative for companies with more than two hours a day of point-to-point international long-distance traffic, the company says.

In the U.K., GSDN will interconnect with British Telecom's International FeatureNet service, giving users virtual network capabilities throughout the U.K. and access to the other virtual network services overseas.

In addition to voice, the connection supports facsimile and data communications at speeds upt to 9.6 kb/s.

MCI's Plans

MCI Communications Corp. has also announced plans to link its Vnet virtual network service with International FeatureNet, adding to its array of international services, which include:

* voice,

* telex,

* fax,

* high-speed data,

* and electronic mail services.

To expand its global presence, MCI acquired the international record carrier RCA Global Communications in 1988.

The following year it bought 25% of Infonet, making MCI the largest shareholder in this value-added network provider.

This past May, MCI announced plans to interconnect its electronic mail service, MCI Mail, with eight United States and international carriers, covering France, Switzerland, Korea, and Australia.

MCI has also teamed up with Germany's Deutsche Mailbox, a leading European electronic mail provider, to supply MCI Worldmail to seven major European countries.

Recognizing the growing user demands for "one-stop shopping" for international services, MCI International inked a deal with Belgium's telecommunications authority in June to give customers a single point of contact for ordering full trans-Atlantic circuits between the United States and Belgium.

Closer to home, MCI opened the first international fiber optic cable interconnection with Mexico in October.

The new gateway connects MCI's domestic fiber optic network with Mexico's telecommunications network, giving MCI's customers expanded high-quality data, voice, and facsimile communications with business centers in Mexico.

Sprint Joins Fray

This year saw a new entiry in the international communications arena.

Sprint International was formed last January from the combination of US Sprint's international voice division and Telenet Communications Corp. which is headquartered in Reston, Va.

Sprint International provides:

* direct dial voice service to 156 countries.

* packed-switched data links to 94 international locations,

* and videoconferencing services to 25 nations.

It also markets US Sprint's electronic messaging service, SpringMail, which serves more than 340,000 users and has been licensed as a public E-mail system or service in 20 countries.

Using any standard data terminal, PC, or communicating word processor, SprintMail subscribers around the globe may create documents and send them to a recipient's electronic mailbox, or to fax and telex machines.

They may also have them delivered as hard-copy letters via the U.S. Postal Service.

During the past year, Sprint International has expanded its SpringNet data network with 20 switching centers in Europe, the Pacific Basin, and Latin America.

Next year, it will install nodes in 45 additional countries and overseas locations.

Last July, Sprint International entered into a joint venture with the Soviet PTT to operate a switching center in Moscow.

This agreement provides Soviet computer users with access to databases and online services in the United States and throughout the world.

In addition, the new firm--Sprint Networks USSR--will provide SprintMail electronic messaging service both domestically and internationally, and will link the domestic and international telex networks operated by the Soviet PTT.

Soviet Services

As demand for data communications services grows, Sprint Networks USSR will distribute Sprint International's Telenet packet-switching equipment to form the backbone of the Soviet Union's first data communications network.

Fiber optic links form the backbone of the SprintNet data network, which offers a number of global value-added services.

Included are electronic messaging, electronic data interchange (EDI), and public database access to subscribers who can sign onto the network through the switching center.

As part of its expansion plans, Sprint International is spreading its fiber optic networking capabilities into the Pacific Rim countries.

In addition to its co-ownership of PTAT-1, US Sprint is participating in the Asia-Pacific Submarine Cable.

By 1993, this project will provide a 560-Mb/s link between Tokyo, Shanghai, Hong Kong, and Singapore.

Fiber optic technology is also a key element of the Global Virtual Private Netwok (GVPN) service introduced jointly by US Sprint and Cable and Wireless earlier in the year and demonstrated at the ICA in New Orleans.

GVPN provides international private networking capabilities normally associated with leased lines on an "as-needed" basis.

It is the first service to result from a 1989 agreement between the two firms to offer jointly a group of integrated communications products and services marketed as one brand and supported by one-stop global service support.

BT's Network Services

One-stop shopping and support for data services worldwide is also a major element in British Telecom's Global Network Services (GNS) offering unveiled at the TCA show in San Diego last September.

GNS will offer enhanced services based on data-handling facilities shared, leased, or owned and managed by British Telecom in 20 countries.

They integrate a variety of facilities:

* the value-added network in the U.S. operated by BT Tymnet>

* British Telecom's managed X.25 packet network in the U.K. (PSS) and its international service IPSS>

* and the network nodes operated by BT Tymnet to provide value-added data services in 18 other countries--this represents an increase of seven in the last year.

In addition, GNS will offer transborder services in 84 other countries.

In 34 of these, where the local public data network is based on Tymnet technology, enhanced data services similar to GNS will be available.

In total GNS access will reach more than 100 countries.

GNS will conform to international standards and offer a common set of features in the U.K., U.S., and all other countries where it is available.

Each customer will be offered one-shop shopping--a single point of contract with British Telecom for ordering and providing service and for reporting and repairing faults for all GNS services in a particular location.

There will also be the option of single currency billing.

GNS will use British Telecom's Concert network management capability to offer customers integrated end-to-end data network management.

To support this feature, British Telecom has opened a $7 million World Wide Management Center at Oswestry, England, where up to 30 network mangers are on duty 24 hours a day to watch for and remedy any trouble spots.

TRT/FTC, the international communications subsidiary of Pacific Telecom Inc., has interconnected its virtual private line networks service with British Telecom's International FeatureNet service to provide its customers with a number of new features and direct access to international destinations and overseas virtual private networks.

It has also introduced a trans-Atlantic service called Bandwidth-On-Demand, which provides international satellite channels to firms requiring high capacity for occasional use.

Scheduling Time

With the service, users can schedule satellite time from their premises using a PC or Minitel terminal without having to notify the carrier.

Bandwidth in increments of 64 kb/s can be reserved within several minutes of transmission time.

Fixed costs cover the port, the dedicated line between the user and the TRT/FTC switch and direct access to the reservation system.

Variable costs apply to space segment usage--speed of service plus time on-line.

The major satellite carrier, Comsat, offers an all-digital transmission service at rates from 64 kb/s to 8 Mb/s for point-to-point and point-to-multipoint applications.

International Business Service is designed to allow convenient access to satellite facilities through urban teleports and small earth stations near the user, eliminating the need for costly land-line connections at both uplink and downlink sites.

VSAT Links

Another data distribution and collection service, called Datanet, uses a hub earth station and VSATs (very small aperture terminals) located at remote sites.

The service is intended for communications-intensive applications such as news distribution, travel reservation systems, and banking and financial reporting systems.

Comsat says it is researching a new generation of satellites that will bring about the widespread use of smaller earth stations on or near the customer's premises.

These satellites will be able to aggregrate traffic from various locations to utilize satellite capacity efficiently and eliminate the need to use many costly terrestrial lines and tandem switches.

According to Comsat, satellites now on the drawing boards will provide even greater digital capabilities and assure continued satellite competitiveness well into the next century.
COPYRIGHT 1990 Nelson Publishing
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1990 Gale, Cengage Learning. All rights reserved.

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Title Annotation:includes a related article on international networks
Publication:Communications News
Date:Dec 1, 1990
Previous Article:Voice processing solves global time-zone problems.
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