When Friedhelm Hillebrand starts talking about those days when mobile telephony went digital, the listener is torn between sheer amazement and pure fascination. Hillebrand was responsible for the German contributions to the development of the multinational GSM standard in mobile networks and the introduction of the D1 network, which saw the light of day exactly 25 years ago, on 1 July 1992. We spoke with Friedhelm Hillebrand at his home in Bonn about the largest and most exciting Detecon project of all time called 'Digital Mobile Networks'. And about why he did not become rich with the invention of the SMS (Short Message Service), but is still very satisfied.
Mr Hillebrand, do you still remember the beginnings of the GSM project?
The development began in what was actually a hopeless situation. In the mid-80s, we only had national networks in Europe that did not work across borders. The manufacturers were watching over their home markets, the telecom network operators were not very interested because they considered the potential to be low. At that time, we had the B network with 27,000 subscribers. That had to be closed because of overcrowding. Therefore, the basic fee was raised to 180 marks without further ado. When the C-network came in 1986/87, the first car phones cost about 4,000 Marks. And there was no hope that it would ever become cheaper. The frequencies we needed for mobile radio were almost all occupied by the military. The only way to escape these framework conditions was to have a European standard.
Not the best time to take on the job of developing a digital mobile network, is it?
I came into mobile networks in 1983. The assignment was to develop a Franco-German analogue network. But what were we supposed to do with another analogue network? SEL Alcatel had found out in a large research project: Digital technology is possible. In a market study they predicted one million subscribers in Germany in the year 2000. They were laughed at as cranks.
Nevertheless, the project got off the ground. How did it come about?
My team and I were intrigued and sat down and thought: Why not? The first application was car phones. Our market and network planning showed: it is realistic, but only if there are sufficiently high numbers of terminals in a common European market. In the end, we, Dr. Klaus Spindler, Frieder Pernice and I, were also able to convince the then Post Minister Schwarz-Schilling that we needed a digital pan-European network from the beginning of the 1990s. With this, we went to the existing European working group GSM (Groupe Spécial Mobil) in autumn 1984, which was supposed to standardise a pan-European system, but had been bobbing along for a few years. Our Franco-German plan had the effect of a drumbeat throughout Europe, because suddenly two countries that had about 40 per cent of the market declared that they wanted a European solution soon.
And did you manage to get other European countries on board immediately?
They were very hard and protracted negotiations. There was a very intensive planning phase until 1987, until we gradually reached agreement in the GSM group on the basic concepts of the system. This involved in particular services such as SMS, system architecture, voice digitisation with low bit rates and digital radio transmission. The selection of the digital radio transmission method was particularly difficult. In the decisive GSM meeting in February 1987, 13 European countries agreed on a narrowband TDMA method, while we as the German delegation had the specification to support a wideband TDMA method. This threatened to collapse the whole project, as unanimity was required.
Default means: You were not at all convinced that the broadband TDMA method was the better solution?
In Germany, at the working level, Armin Silberhorn, Frieder Pernice and I also considered the TDMA narrowband method to be technically and economically better. In a lengthy discussion process in the then DBP Telekom, we were able to convince the minister of this. Our French colleagues managed to do the same. The breakthrough came in May 1987 at a meeting in Bonn, where the four big European countries Germany, France, Italy and the UK agreed that the majority opinion of Madeira should be unanimously supported. In the autumn of the same year, the operators of 15 European countries committed themselves to introducing the GSM system from 1991. This set a stable framework for further development.
How did Detecon get involved?
Things were now getting serious in Germany. And it quickly became clear, above all, that there would be competition and that this was not possible in the existing structure of the old 'Bundespost Telekom'. Telekom manager Armin Silberhorn finally made the suggestion that the whole thing be set up as a project at Detecon. Detecon's managing director was the former state secretary for the postal service, Dietrich Elias, who at the time was on his way to help Telekom in the transition to competition.
Friedhelm Hillebrand
Friedhelm Hillebrand studied electrical engineering with a focus on communications engineering (telecommunications) at RWTH Aachen University. From 1970 to 1987 he worked in various management positions at Deutsche Bundespost Telekom, and from 1987 to 1992 at Detecon. After the introduction of the D1 network, he was represented in various high-ranking international committees on mobile communications. Since 2002, he has been managing partner of the consulting firm Hillebrand Consulting GmbH, which advises and supports patent attorneys, network operators and manufacturers in patent matters. He is also the author of several technical books:
- The Pioneering Period of the GSM Standard and the D1 Network from 1982 to 1992 (J. Schlembach, 2013).
- Short Message Service - The Creation of Personal Global Text Messaging (John Wiley & Sons, Ltd., 2010)
- GSM and UMTS - The Creation of Global Mobile Communications (John Wiley & Sons, Ltd., 2002)
Friedhelm Hillebrand has been inducted into the 'Wireless Hall of Fame' by the American Wireless History Foundation.
With that, the die was cast?
In the spring of 1987, I was given leave to go to Detecon to prepare the new project. In early summer 1987, the decision was made that the Detecon project would run 'Digital Mobile Networks'. There was an initial capacity of 40 posts. There I sat alone and was allowed to take three former postmen with me. The rest were to be recruited in the market. We didn't have any employees yet, but I first ordered furniture for 40 offices in our first office in Friesdorfer Straße in Bonn. Because I was sure that things would have to start rattling around soon if we wanted to be successful.
How did the start from 'zero point' turn out?
In August 1987, I moved into the 40 offices alone with two secretaries. Finally, in the autumn, the three post office colleagues from Darmstadt arrived. Since we had little know-how in system development, Dietrich Elias wrote to the industry asking them to give us twelve people, each on leave for a good year. They were to check the results of the standardisation and make suggestions for improvement. A good idea, because in the end both sides benefited. We were able to benefit from their know-how, and the industry quickly gained knowledge about the new standard.
What happened next?
At the end of 1987, we had just under 40 employees. And we almost doubled this number every year. In 1992, about 500 Detecon employees were working on the Digital Mobile Networks (PDM) project and about 100 on the Mobile Networks Marketing (PPM) and Mobile Networks Sales (PVM) projects. Looking back, PDM was probably the largest and most complex project Detecon has ever managed. We built everything up internally 'from scratch' and were also represented in 45 European working groups. In parallel, we developed the concept for the D1 network, commissioned the delivery services and implemented the network step by step. For the network planning, we founded seven Detecon regional offices, spread all over Germany.
How did you manage to recruit so many employees in such a short period of time?
A big challenge. Recruiting staff was very difficult. Because the whole thing was planned as a project, we were only allowed to give employees temporary employment contracts. Neither the Post nor Detecon could give any guarantees of employment. So in the first place we got a lot of good young people. Graduates who didn't care about fixed-term contracts. At the end of 1989 we already had 175 employees, but of course we had no managers. At that time we had a real crisis. Finally, after long negotiations, also with the support of the Telekom mobile phone side, I managed to get all the contracts de-fixed. On this and many other occasions, we found open ears with Roland Mahler and his team, our clients at Telekom.
How did the project go in the meantime?
Mannesmann Mobilfunk started development in 1989. And what hardly anyone knows: they always had a bigger team than we did. One of our biggest problems at that time: we had to take the entire German telecommunications industry with us. Mannesmann, on the other hand, was able to concentrate on a partnership with Ericsson, who we would also have liked to have on board because of their technological competence. We had Siemens, Philips/PKI, SEL Alcatel and Bosch on board, and later Motorola. Getting all these technologies to work together was sometimes a bit adventurous. But the project had a momentum: it was the biggest development project ever done in the German telecommunications industry. Because everything had to be done anew: digital radio transmission, voice digitisation, most network functions, terminals.
It sounds like everything went pretty smoothly.
In principle, yes, but it was a very big effort. It only worked because the staff developed a pioneering spirit and such great enthusiasm for the project as I have never seen again. Then, unfortunately, something came along that none of us had taken into account. At some point I asked the General Directorate of Telekom the question: What about subscriber data management and fee data post-processing, anyway? In other words: How are subscribers managed and bills written? The Telekom data processing department immediately waved me off. So the topic landed on our desk as well. A highly complex topic that kept us all intensively busy over a long period of time.
Did the introduction of the new technology work out without a mistake?
In 1991, the technology was made available for acceptance. We did this in several stages. First, the network components and the IT systems were tested separately. Here, the expected numbers of errors occurred that had to be dealt with. The most critical stage was the last one in Münster. There, a configuration was set up that contained all network components and the entire data post-processing for the D1 network. We had specially set up a container settlement for our staff. There were major problems in the interaction of network and IT components. But all these problems could be solved adequately. It helped us that the network launch could not take place until mid-1992 due to a lack of terminal equipment. We used this time intensively for testing and improvement, so that the start of operations was quite problem-free.
Success proved that you were right...
Yes, from mid-1992 the D1 network worked very well. Already in 1993/94, a heavy load set in because of competition and cheaper terminals. It was good that we had such a big team, because this team could carry something. The demand increased rapidly. At that time we had a planning horizon of 10 million subscribers in the D1 network, but this number was quickly far exceeded.
Did they believe at the time that mobile networks would one day replace fixed networks?
No. In 1984, I looked at the USA and thought: Yes, one million devices per year should also be possible in Europe. But today, one billion devices are produced per year for the mobile networks. 1,000 times as many! In retrospect, it often sent a shiver down my spine how courageous it was back then that we fully relied on the digital system. Because there were so many software, hardware and standardisation risks involved.
The topic of data transfer: Was this an integral part of the planning from the beginning or rather a coincidence or waste product?
I was able to bring a special expertise to the topic. I had previously worked in data communications and was responsible for the Datex-P data packet switching network in Germany, a precursor technology of the Internet. I came up with a number of concepts for data transmission in the GSM network. One of them was the 'Short Message Service', the SMS. Eventually, I became the founding chairman of the GSM subgroup 'Data Services in the GSM System'. In cooperation with the device manufacturers, this has resulted in a good set of standard data services.
Did you expect the SMS to have such a great career?
No one had expected that. A Vodafone manager said in about 1993: "Why should I type something on this weird keyboard when I can call the guy?" Fortunately, we classified SMS as an 'essential service' back in 1985. This meant that every network and every terminal had to support it. I obtained this decision in the European working groups.
So why did the SMS become such a commercial success?
Young people discovered the topic for themselves. SMS very quickly became part of youth culture, also because it was cheaper than a phone call. And of course it was a differentiator for the young people: they could suddenly do something that the 'old people' couldn't. Unfortunately, SMS was not developed sufficiently because the network operators rested on their money. In 2008, more than 100 billion euros were made worldwide with SMS. Most of this was profit because the costs of providing the service were marginal.
In principle, with SMS you indirectly co-invented one of today's most popular internet services worldwide, namely Twitter.
Yeah, sure. And Whatsapp too. The basic concepts are the same. A journalist once said something nice: 'Since you are the father of SMS, you must be the grandfather of Whatsapp and Twitter.
Does it feel like that for you too?
Yes, it is very nice to have had the chance to contribute to such great developments. Although I didn't get anything out of it directly financially. We were a public service, we didn't register any patents. We couldn't have the really big wealth that youngsters get today because it was a different time. That's all right. Who can claim that seven billion people carry something of their own around in their pockets all the time?
What do you personally use today, SMS or Whatsapp?
Primarily email and SMS. Since I don't have grandchildren, I haven't had the impetus to enter the Whatsapp world. I use SMS intensively in my private life; in business, primarily for communication with partners who are in meetings. There, the phones are usually muted. In business, SMS is still the best way to reach someone in person quickly and securely.
What is the future of SMS among the competition of internet messaging services?
The SMS has some advantages. It is very robust and it works out of the box in every device. In 'native mode', without me having to update anything. You don't need to know an address, just the phone number. And SMS has excellent coverage, because it uses the signalling channels, i.e. the control channels at the transition between two radio cells. So you can use SMS in places where telephony and internet no longer work.
What will be the most important uses of SMS in the future?
Clearly in machine-to-machine communication. For example, meter readings or safety solutions in cars, such as automatically transmitted accident reports. And of course in online banking, with the 'Mobile TAN' procedure. And last but not least, the application is of course safer from hackers than internet messaging services.
When you look back on this exciting time: Did you make any fundamental mistake or would you do anything differently today?
Of course, you also make mistakes in such big projects. The point is always to learn from these mistakes. Looking back, we should have been much more involved in the overall telecom strategy. But I don't know if we could have succeeded. The contract with Telekom did provide for a high-level steering committee at board level for the project, but that never came to life. Therefore, we always had a certain communication gap. We were not able to make it sufficiently clear that the GSM system is not a mobile phone system, but a mobile networks system. After all, with SMS, for example, we quickly wiped out paging services from the market.
What memories do you associate with Detecon?
Detecon was a stroke of luck for us because we were freed from the rigid rules of the civil service. And because, on the other hand, there was also a spirit at Detecon not to define our own rules, but to always behave in a way that is appropriate to the situation and the project. If I look at what we had to do back then from the point of view of a Detecon cross-sectional department, property management or human resources, the dynamic growth of this project must have been pure horror. It put a lot of strain on the company, but these departments always worked very cooperatively with us and faced the challenges with us. I am very grateful for that.
Mr Hillebrand, thank you very much for the interview! Can you think of a little anecdote at the end?
I was walking along the edge of the forest here years ago. I met some eight- or nine-year-old children who were typing text messages into their phones. I asked them: 'Do you already know how to do that? The children answered: 'We can. But you? Can you do that?' I said, 'I invented it!' The children laughed loudly and one shouted: 'I've never heard such an excuse!
Thank you very much for the interview, Mr Hillebrand.
The interview was conducted by Thorsten Cöhring, Detecon.