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Europe Pushes ISDN to Achieve Parity with the United States.

In the United States, the integrated services digital network (ISDN) is viewed as the ultimate network, allowing users to access a variety of voice, data, image and video communications services with the ease of placing a telephone call. In Europe, where analog technology lags considerably behind that of North America, ISDN is also viewed as a vehicle for leapfrogging into state-of-the-art digital communications and attaining parity in technology and quality of service with the United States and Canada. That accounts for why, collectively and individually, european countries are so busy planning the early introduction of ISDN services.

France's ISDN plans involve a two-stage strategy. As a first step, it is overlaying its existing network with digital local loops to provide an integrated telephone and data network (ITDN) with switched end-to-end service at 64 kbps. Its launch of the Telecom 1 communications satellite will also help by providing additional digital links and broadcast capabilities. To complete its plan, the French PTT will complement the ITDN with a nationwide optical fiber network, paving the way for a wideband ISDN capable of handling all communications services, including the transmission of moving pictures.

Britain's plans are equally expansive. "British Telecom is in the vanguard of the world drive towards integrated digital networks, which are essential for Britain's future economic prosperity," says British future economic prosperity," says British Telecom Chairman Sir George Jefferson. "We shall have a basic national digital network in operation by 1985/86 with nationwide coverage by 1988."

By then, Britain's trunk Integrated Digital Network should be complete. Long beforehand, however, British Telecom will be offering ISDN services. The British have rightfully determined that the user of such services is not concerned with the in ternal workings of the network, but only in access and ease of use. That's why British Telecom is starting a pilot ISDN service this October based on its System X exchanges and an access technique it calls IDA, for Integrated Digital Access.

Subscribers in the London area will be the first to use the service, which will expand in 1985 with the addition ISDN exchanges in Birmingham, Manchester and a second one in London. Service will be available from 60 access locations when the pilot stage ends in December 31, 1985. At that time, British Telecom plans to market the service as a full-fledged national ISDN offering with service available from 1,000 access locations by 1988. Initially, the IDA link will provide users with two channels, one at 64 kbps and one at 8 kbps. When local transmission capacity allows, however, access will be upgraded to two 64-kbps channels. In addition, subscribers will be able to choose multi-line IDA access at a rate of 2 Mbps.

Meanwhile, the West German PTT plans to migrate towards an ISDN by 1987. Beginning next year, ten German cities will participate in ISDN field trials in which each of the 4,000 planned subscribers will have access to either a Basic Access channel at the 144 kbps rate, or Primary Access channel at 2.048 Mbps. Local excahnges will be modified to incorporate out-of-band common channel signaling, which will be performed according to CCITT Signaling System 7.

The Italian PTT, through its major telephone company, SIP, also plans to offer ISDN field trials this year. The participants will have access to 80-kbps, full-duplex channels provided by two-wire loops. Services supported in the trials will include digital telephony, interactive data, slow-scan video, digital facsimile, videotex, teletext and circuit-switched access to an X.25 packet-switched network. SIP will distribute standard ISDN equipment in 1986 and projects that all of Italy will be interconnected by an ISDN equipment in 1986 and projects that all of Italy will be interconnected by an ISDN in 1990, when 90 per cent of local loops will be digital and broadband services at rates to 2.048 Mbps will be available.

The Swedish PTT has also established an ISDN evolution policy, based on the gradual digitization of its telephone network. Attention will be directed initially toward the business community due to the potential market demand there. ISDN Unifies Europe

Evidence of the importance European nations attach to ISDN came recently when the prestigious Council of Ministers of the European Economic Community (EEC) agreed to a unified initiative on communications. One of the xis points agreed on by the Industry Ministers of the ten EEC countries was the need for "harmonization" of network standards, particularly ISDN. The fear is that ISDN standards might suffer the fate of the X.25 "standard," which reportedly has been implemented in 25 different versions.

Responding to the request of the EEC ministers, senior officials from the 26 countries in CEPT (the Conference of European Postal and Telecommunications Authorities) agreed at a private meeting in Paris to speed up their program of network harmonization and in terface standardization. The work is expected to take some time and no details were released of the measures that would be taken to achieve it. However, a spokesman said that a central theme would be digital interfaces for terminal equipment to facilitate end-to-end communications between users across national boundries. CEPT also agreed to handle the technical aspects of harmonizing the implementation of CCITT standards on ISDN.

The six-point plan endorsed by the Council of Ministers was drawn up by the European Commission to combat the growing divergence and uncertainty of communications development in the Community and the fragmentation of its markets. It opposed common R&D programs and coordinated medium- and long-range planning, and called for joint development of transnational communications links and the communications infrastructures of poorer EEC countries.

In addition to the harmonization of standards, the plan recommended opening public procurement to suppliers in other EEC countries. An effectively harmonized European market would represent 30 per cent of the world market for "telematics," whereas no European country accounts for more than four per cent of the world market on its own. Such a harmonized market would give European manufacturers a significant advantage in developing products to compete with the much-feared Japanese, whose home market accounts for 12 per cent of the world.

Advanced communications facilities are also seen as essential to exploiting the devices and services to be developed under the European Espirit R&D program and under national schemes such as Britain's Alvey program (see "Fifth Generation Systems: East Meets West in Battle for Info Supremacy," Communications News, July 1984, page 54.)

In its report, the European Commission complained that communications authorities are poorly motivated to get advanced networks operating quickly. According to a recent government study, the United States is opening up its communications markets to foreign competitors at a much faster clip than other countries are opening their markets to the United States. The 218-page report by the International Trade Commission said that United States imports of communications equipment exceeded exports last year for the first time and predicted a trade deficit in such equipment of $3 billion by 1993. The study showed that the Japanese have made the biggest inroads in the USA market, particularly in terminal equipment and certain switching gear. Imports from Japan of such equipment rose from $129 million in 1979 to $582 million last year, an average annual growth rate of 45.7 per cent. The commission's study was requested by Senator John Danforth, Republican of Missouri and chairman fo the Senate Trade Subcommittee. Senator Danforth has introduced a bill that would give trading partners two years to remove communications trade barriers. If they do not, the United States would raise tariffs against them. They use "cost-plus" pricing policies that hide the market value of their services from them, operate on a public service philosophy rather than as leading-edge industries, and are run as bureaucracies. Also, stimuli have been necessary to break the deadlock caused by lack of user interest in standards before they are available in products, matched by a lack of commitment to them by manufacturers before users demanded it.

One stimulus often advocated is the use of "enlightened government procurement" to encourge adoption of standards. Britain's Prime Minister Margaret Thatcher recently instructed her government to overhaul its internal communications system and impose common standards on all suppliers in the process. By setting standards, the British government hopes to eliminate the compatibility problems that could hinder the widespread use of computer and office automation technologies throughout British industry and commerce. Further, by replacing existing facilities with an integrated voice and data network, the British policymakers expect to save money and provide government departments with a sophisticated infrastructure to support increased productivity. It's estimated that the move will save United Kingdom taxpayers $22.5 million, while helping the British information technology industry with $75 million in orders.

Priorities for equipment to be standardized before 1985 include computer and terminal interfaces and PBX features. Target dates include local area networks in 1985, videotex and teletext in 1986, file transfer and terminal protocols in 1987, digital access from PBXs to public networks from 1985 to 1987, and digital access from workstations to PBXs in 1988. Britain Takes the Lead

British Telecom says its pilot Integrated Digital Access service is not intended as an experiment or field trial. The idea is to give users an early introduction to the capabilities of ISDN and to encourage its rapid exploitation. Accordingly, the pilot service will quickly expand to become a national ISDN. By early next year, service will be available through local exchanges in London, Birmingham and Manchester. British Telecom says the service will extend to 400 locations by 1987 and to 1,000 the following year. During this time, new services and facilities are planned, with international links to other ISDNs and data networks.

For the pilot IDA service, British Telecom will use a non-standard access rate of 80 kbps, made up of a 64-kbps B channel for voice, data, high-speed fax and the like, an 8-kbps B channel for slower-speed data and an 8-kbps D channel for signaling. Explaining its choice, British Telecom says it needed to adopt a rate suitable for the United Kingdom local line characteristics and employ already developed transmission techniques.

One of these is burst mode transmission at 256 kbps, in which information is sent up and down a pair of wires in discrete timeslots without mutual interference. The other, more promising technique uses the echo cancellation principle and will effectively lower the transmitted bit rate. Both techniques will be used in the pilot service. British Telecom expects to transmit local loops, and estimates that at least 80 per cent of its business customers can be served in this way.

In addition to single-line IDA, British Telecom will also offer multi-line IDA service at two Mbps, principally for use with PBXs designed to operate with ISDN networks, and termed ISPBXs. Initial tariffs call for a connect charge of $195 for single-line IDA and an annual rental charge of $224. Multi-line service will have a connect charge of $1,050 and an annual rental of $2,100. This compares with the present annual rental of an equivalent 30-channel line of $3,700.

Customer access will be provided through two types of Network Terminating Equipment. NTE1 will provide a single user data port, and NTE3 a six-port facility. Connection charges for NTE1 and 3 will be $1,050, and the annual rental will be $770 for NTE1 and $840 for NTE3.

The NTE1 includes a digital telephone, keypad, display and single data port which can support X.21 bis or the leased-line version of X.21. The NTE3 has no built-in telephone, keypad or display since it is designed for applications such as the automated office where call set-up is controlled by the user's equipment. Terminals having the full X.21 interface may initiate calls automatically. Alternatively, separate remote keypads may be used.

Up to six terminals may be connected, with the NTE providing arbitration in contention for the two IDA channels. Two special interface options are available: an analog two-wire option for connecting telephones or facsimile equipment and a V.24 300-bps modec. The latter performs the functions of both modem and codec and allows interworking with existing V.24 modems in the analog public telephone network.

IDA will provide access to a wide range of services, including telephony, circuit-switched and private-line data, packet-switched data, telex, teletex, high-speed facsimile, slow-scan TV and photo videotex. British Telecom has been holding seminars for terminal manufacturers to encourage development of new devices to take advantage of the switchable 64-kbps service. Many of these manufacturers have signed up for the pilot IDA service to develop and check out their new terminal designs. British Telecom says it is negotiating with a number of manufacturers and the Department of Industry to develop facsimile terminals working at 64 kbps via an X.21 interface. The units will be able to send a page in about five seconds.

For slow-scan TV applications, British Telecom has developed a system operating at 64 kbps via an X.21 leased line interface which refreshes the picture every five seconds. Likewise, it has produced a photo videotex terminal and data base for storing and displaying picture-type information. The information may be displayed either as a full-screen picture, a picture plus text, or a picture overwritten with text. Terminal-to-terminal communications will also be possible for electronic mail applications.

For the multi-line IDA service, British Telecom is working with PBX suppliers to develop the appropriate 2-Mbps interface and ISDN capability. The ISPBXs will use a common channel signaling system called DASS II (Digital Access Signaling System), until CCITT standards become available.

During the pilot service, British Telecom will seek improved forms of local two-wire transmission to upgrade the second B channel to 64 kbps. This will bring the service in line with the likely CCITT standard of 144 kbps, comprising two 64-kbps channels and a 16-kbps signaling channel. British Telecom is also considering adding network storage for a variety of electronic mail and voice mail services. There are also plans for combinations of voice and data storage with the appropriate retrieval features to support data-in,

Today, the French network has one of the highest proportions of digital systems in the world: greater than 50 per cent in the local network, and greater than 30 per cent in the inter-city network. To further accelerate the introduction of digital transmission techniques, the French have assigned a substantial role for satellite and optical fibers in their future transmission plans. France is scheduled to put its own domestic satellite, Telecom 1, into service this month via the Ariane launch vehicle, and optical fibers will gradually be installed during the next decade.

Telecom 1 will carry six 25-Mbps transponders operating with a power of 20 watts in the 12- and 14-GHz bands, providing SBS-like services using time division multiple access, demand assignment techniques. Users will have access to links of variable speed from 2.4 kbps to 2 Mbps via earth stations with diameters of 3.5 meters. Besides providing wideband digital links for intra-company communications, the satellite will handle voice, data and video traffic between French government offices and its Overseas Departments. The satellite will have four transponders operating in the 4/6 GHz bands for overseas communications, and two operating at 7/8 GHz for the Ministry of Defense.

The business portion of the network, expected to have about 3,000 users, will utilize a maximum of 320 earth stations, with approximately 150 rural and 40 urban earth stations located in France. Additional earth stations have been installed in Switzerland, West Germany, Belgium and the United Kingdom in the framework of the European Telecommunications Satellite Organization (Eutelsat), voice-out services and, when technology permits, voice-in and data-out services.

In the meantime, several questions remain to be answered: which CCITT recommendations will become accepted standards in 1984, and which will require a further round of four years' discussion to become resolved and adopted? How quickly will companies be able to achieve end-to-end ISDN operation in the United Kingdom and internationally? Will total integration offer the level of security and service possible with separate networks? How readily will the pilot access methods evolve into the final CCITT realization, and what penalties, if any, will users have to pay?

As an alternative to ISDN, several large United Kingdom organizations are adopting the more cautious approach of building a digital core network with conventional access methods. However, others are opting for the IDA pilot service in the belief that a little "hands on" experience in the new service can be an invaluable investment for realistically assessing when and how to take the big plunge. France Stresses Video Services

France is also well on its way to an integrated telephone and data network (ITDN) based on time-division switching centers interconnected by a hierarchy of digital channels operating at 2, 8, 34, 140 and 4 X 140 Mbps. Historically, the French have been pioneers in electronic TDM switching and digital transmission techniques. France installed the world's first electronic TDM switching center in its telephone network in 1970. By 1980, over 70 per cent of equipment ordered for the French telephone network was of the electronic TDM type, and since then all new equipment has comprised TDM switching units and compatible digital transmission systems. Eutelsat will use part of the capacity of Telecom I for specialized intra-European services, while West Germany's Bundespost has contracted to use Telecom I to satisfy the digital private-line needs of its national customers.

During the 1980s, optical fiber cables will be used in the French telephone network for both inter- and intra-urban links, as well as for wideband local loops to subscribers. The plan is to cable homes at the rate of one million a year so that one in every two French families could be connected to an optical fiber cable network by 1995. At that time, the local networks will be interconnected through the high-speed national monomode transmission system.

In addition to the national plan, two other tests are underway. In Biarritz, an optical network links the homes of 1,500 subscribers to provide access to 12 FM stereo channels, 15 TV channels and switched services that include videophone, videotex and data banks with image. In Lille, development of a local fiberoptic cable TV system is underway for 50 subscribers, increasing to 3,000 by 1985.

For its long-haul network, the French PTT is working with industry to develop cost-effective monomode systems operating at 1.3 [mu] m, and researchers in its CNET labs are experimenting with similar systems at 1.55 [mu] m. Depending on traffic growth, France may implement an optical system between Paris and Lyon, possibly extending to Marseilles. The system could be operational by 1985 using multimode fibers, or by 1986 or 1987 using monomode. $TThe long-distance optical fiber link between Le Mans, La Fleche and Angers employs both monomode and multimode fibers with a transmission rate of 140 Mbps, repeaters spaced at 25 km and lasers emitting at the 1.3 [mu] m wavelength. An advanced 42-kilometer monomode fiber link being tested in Brittany uses a 1.55 [mu] m wavelength and has a rate of 4 X 140 Mbps. Like the rest of the world, France is leaning towards monomode networks.

France plans to use the optical network to convert its 64-kbps integrated telephone and data network into a wideband ISDN capable of handling all communications services, including the transmission of moving pictures. Work is underway on the switching equipment, local loops and customer premises equipment for the ITDN, with the goal of end-to-end 64-kbps switched digital service becoming available next year.

According to Alain Roche, who has been in charge of the French PTT studies on ISDN since 1977, the local part of the network will be introduced as an overlay to the existing network by selectively digitizing subscriber lines. These digital lines are routed via the main distribution frame of the local exchange to a new subscriber line concentrator, the digital connection unit, or DCU (see figure). This unit is functionally similar to existing subscriber connection units and can, in fact, handle analog subscriber lines accessing the ordinary telephone service. The DCU connects to a functionally enhanced digital telephone exchange capable of performing 64-kbps circuit switching.

Other services offered to ITDN subscribers will be carried by other existing dedicated networks. Network interworking is provided by a centralized machine known as the dedicated network interworking point (DNIP). Roche explains that remote subscribers will be connected by means of multiplexer-demultiplexers (Muldex), concentrators or, in certain cases, microwave links. Transmission systems in the local network will operate at 144 kbps for basic connections and 2 Mbps for large PBX installations. A further intermediate bit rate transmission system will be used for connecting medium-sized subscriber installations, muldexes and remote concentrations.

Interworking with the telephone service is accommodated by the DCU, which is a class four exchange in the telephone network. The ITDN also provides access to the Transpac public data network via a 64-kbps link which can be set up semipermanently or on a switched, call-by-call basis. A special gateway provides interworking between Telecom I and the ITDN and there will be permanent access from the ITDN to existing leased-line services and the telex network.

Transpac was Europe's first public data network to support the X.25 standard. It began service in 1978 with 12 switching centers and a capacity of 1,500 subscribers. Today there are over 11,000 direct subscribers and 22 switching centers in 20 cities, and the transmission potential has been increased from 50 bps to 48 kbps. There are also 1,100 additional users who access the system through the public telephone and telex networks at rates from 300 to 1,200 bps. Two-thirds of direct connections to Transpac employ the X.25 protocol, making it the world's largest X.25 network. Transpac transmits about 40 billion bits and treats 100,000 calls a day, and during peak hours handles 5,000 simultaneous communications. By 1990, the French PTT expects to have 100,000 subscribers. Datacomm Surges in Europe

In Europe as a whole, demand for data communications services will grow three-fold in the six years between 1981 and 1987. That's the main conclusion of a study on data communications in Europe commissioned by the Eurodata Foundation on behalf of its membership of 18 European PTTs.

For its study, the Foundation used the Network Termination Point (NTP) . . . a modem or other type of data connection . . . as the basic measure of datacomm usage. The number of NTPs in Western Europe in 1981 was 613,000, and this number will grow by a factor of 2.8 to 1,742,000 in 1987. The number of terminals using PTT services will grow even more rapidly . . . from 1,095,000 in 1981 by a factor of 3.8 to 4,200,000 in 1987.

In 1981, the United Kingdom, France, West Germany and Italy accounted for 69 per cent of the NTPs in Western Europe, while the four smallest countries accounted for less than one percent between them. For the rest of this decade, the least-developed countries will experience the biggest datacomm growth rates, but the same top four countries will still account for 67 per cent of the NTPs in 1987. The United Kingdom will continue to lead the other countries in terms of installed NTPs, but it will experience the slowest growth factor of only 2.15 between 1981 and 1987. Greece and Ireland will grow fastest in this period, by a factor of over ten and six, respectively.

The banking sector dominates Western European data communications today with almost 30 per cent of all NTPs. Although this proportion will fall to 22 per cent by 1987, this sector will remain by far the largest user of data communications. Manufacturing, distribution, DP services and government sectors are all large users of data communications.

General management use of data communications will maintain its leading position in the 1980s, but established applications that are restricted to the industry sectors approaching saturation will lose ground. By 1987, for instance, person-to-person communications will have overtaken banking transactions as the second most important application type. Among specialized terminals, the most spectacular growth will be experienced by the digital facsimile terminal for person-to-person communications, and by the automatic teller machine.

According to the study, the public switched data networks will make a substantial impact on data communications usage in the coming years, and by 1987 will account for 20 per cent of all NTPs. Nevertheless, existing network types . . . the public switched telephone network (PSTN) and analog leased lines . . . will continue to be widely used, accounting for more than 60 per cent of all NTPs in 1987. Packet-switching services are available in nearly all countries and the demand for these networks will reach 13 per cent of all NTP by 1987. Circuit-switched networks are also planned in most countries and will accommodate seven percent of all NTPs by 1987. Digital leased circuits are becoming available in some countries and their share of the installed base of NTPs will rise rapidly to 16 per cent by 1987. While the share of analog leased lines will decline, leased circuits as a whole will still account for more than half the total NTPs in 1987. Trend Toward Higher Data Rates

The Eurodata study also confirmed the trend towards higher data rates, particularly 9.6 kbps. The installed base of NTPs transmitting at this speed will grow five times to reach a 14 per cent share of all NTPs by 1987. In 1981, 1.2 kbps was the most popular speed with 28 per cent of all NTPs; in 1987, the most popular speed will be 2.4 kbps with 26 per cent of all NTPs. Public data networks will be most heavily used at transmission speeds of 1.2 kbps, though an increased penetration is forecast for packet-switched services at higher speeds. Despite the availability of high transmission rates on the public data networks, leased circuits of various kinds will continue to dominate high-speed transmission, accounting for 65 per cent of NTPs transmitting at 9.6 kbps in 1987.

Specific details of the public switched data services available from the European PTTs appear in the Eurodata Foundation Yearbook. The publication is an invaluable reference book for any communications manager with an interest in European data communications. In addition to listing technical data and tariffs on existing services, the Yearbook includes information on PTT organization and policy, regulations and procedures for attaching equipment to the networks, and PTT contact points for service and information. It also covers proposed new services and facilities of the European PTTs.
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Author:Edwards, M.
Publication:Communications News
Date:Aug 1, 1984
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