NORDUnet - A succesful collaboration
General Manager Peter Villemoes
Peter.Villemoes@nordu.net
November 1996
History.
NORDUnet is the result of a Nordic collaboration program financed by the Nordic Council of Ministers in the second half of the 1980's. At that time the Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) were building computer networks for research using different technologies, and the purpose of the program was to unite these networks into one common infrastructure to serve education and research in these countries.After a difficult period of network protocol evaluation the program decided, in collaboration with the Nordic national research networks (NRNs), to interconnect them by a multi-protocol structure with TCP/IP as the primary service. This decision, which looks obvious today, was a bold decision at a time when the rest of Europe was busy implementing OSI networks.
NORDUnet was fully implemented in 1989 with connections between the Nordic countries, direct circuits to NSFnet in the USA, and EUnet and CERN in Europe. In that year the network was handed over to the Nordic NRNs, who set up and funded the NORDUnet organization to operate the network. The structure had a capacity of 64 Kbit/s at a cost about 400 KECU per year.
Current connections
NORDUnet's mission is to provide international connectivity to the Nordic NRNs by interconnecting them and connecting them to the rest of the world.NORDUnet carries out its mission by operating circuits and connections as illustrated in the map of Fig.1. The circuits are set up and shared with NRNs in other countries, while the connections are subscriptions to other backbone networks. Not shown in the figure are several no-cost-exchange (peer) interconnections with commercial networks that optimize the bandwidth used for mutual traffic. In this way full Internet connectivity and service quality is assured.
The cost of NORDUnet in 1996 is about 6 MECU for a structure of about 34 Mbit/s capacity. The cost of most circuits are shared with partners at the other end, in Europe as well as in the USA.
As shown in Fig.1 there are also circuits between NORDUnet and the Baltic States, Poland and the St.Petersburg region. NORDUnet provides the research networks in these countries with international connectivity in the same way as for the Nordic NRNs. Most of the circuits and the cost of transit traffic over NORDUnet is subsidized by the Nordic Council of Ministers or the European Commission.
Fig.1 illustrates the dynamic situation of the Internet. Ideally NORDUnet, being a regional network, should obtain connectivity outside the Nordic area via connections to European or global backbone providers. However, to preserve the service level and contain the costs it has become necessary to supplement such connections by direct circuits (shortcuts) to the major countries of Europe.
Figure 1:
Cost-effective solutions
The star topology of the network is mainly determined by cost. All NORDUnet's circuits are international and thus 5 to 10 times more expensive than national circuits of the same capacity. Although NORDUnet operates fewer circuits than an individual Nordic NRN the cost becomes comparable when the international capacity must match the national capacity, which is required because of the high ratio between international and national traffic in the Nordic area.Compared to other regions in Europe NORDUnet benefits from a lower price level for telecommunications in the Nordic area, in particular in the countries who have made most progress towards a free telecommunications market. The price for circuits between the Nordic countries are less than the price for circuits out of the Nordic area, so it is advantageous for the Nordic NRNs to interconnect inside the Nordic area and use common circuits to the rest of the world.
These factors, combined with the recognition by network users and their funding bodies of the benefits of networking for research and education, has made NORDUnet and the Nordic NRNs able to provide services that are the best in Europe and compares favorably with those available in USA today.
The Nordic NRNs collaboration within NORDUnet gives them more influence in international collaborations than they would have individually. E.g. in the European TEN-34 project, which will interconnect the European NRNs at 34 Mbit/s, NORDUnet will participate as one entity on behalf of the five Nordic NRNs, with the result that the lower Nordic cost level is preserved.
NORDUnet is organized as a limited company (A/S) in Denmark. The shareholders are the Nordic ministries of education and research, or institutions belonging to them. Although the A/S form allows unrestricted commercial operation, the shareholders have decided that NORDUnet shall be a non-profit organization serving the Nordic NRNs. The shareholders have elected the directors of the Nordic NRNs as NORDUnet board members, so the NRNs have a direct control of NORDUnet. This is a healthy match to the fact that most of NORDUnet's income comes from the Nordic NRNs.
NORDUnet carries out most of its work by contracts with institutions involved with the Nordic NRNs. E.g. the operation of the node in Stockholm is carried out by the Networks Operations Group of Kungliga Tekniske Högskolan in Stockholm, the nodes in the other Nordic countries are operated by the respective NRNs, and technical management is contracted to SINTEF in Trondheim. Therefore NORDUnet has a small permanent staff only for administration and financial management.
How to manage the tremendous growth of the traffic
As mentioned above, the cost of NORDUnet was about 400 KECU per year in 1989 and has grown to about 6 MECU per year in 1996. These numbers illustrate the explosive growth experienced by NORDUnet. During the period 1990 to 1995 the bandwidth increased by 170% per year and the cost by 50% per year. The good ratio between the two numbers is caused by the combined effect of economy of scale and decrease in the price of bandwidth. However, at a cost level of 45 MDKK/year a 50% yearly increase is a cause for concern. On the other hand an assessment of the size of the cost depends on what it is compared to. If it is distributed over the estimated 250,000 nodes of the Nordic NRNs each will have a yearly cost for international Internet communication of 25 ECU, which compares very favorably with the operational cost of a node.In Fig.2 is shown an example of the growth. It shows the history of the capacity between Helsinki and Stockholm on a logarithmic scale. The nearly straight line fit shows the exponential nature. The successive upgrades shown on the figure were made when the previous capacity was filled up.
Figure 2:
Keep research networks separate
The most significant trait of the development of NORDUnet has been its ability to maintain and improve the quality of service to the Nordic NRNs in spite of the explosive growth in demand. This has assured that the resources committed to networking for research and education in the Nordic area have given maximum value for money by providing the user community efficient networking services.It is a major challenge to preserve this excellence during the coming years with the growing number of Internet nodes as well as bandwidth requirements by its individual applications. Experience from the "commercialization of the Internet", that led to the closing down of the NSFnet and referred universities to commercial Internet providers, has not been encouraging for the universities, because the load on the commercial networks has grown faster than the capacity and has pushed the technology to its limits. The resulting service is not considered adequate to serve as a platform for the development of the next century's applications and network technology, and creation of special structures for universities is now under discussion in the USA.
The experience from the USA, where bandwidth prices are much lower than international prices in Europe, show that maintaining a separate, but interconnected, Internet for research will be necessary in Europe for several years to come, because the high cost of international bandwidth inhibits provision of sufficient bandwidth by commercial providers.
Because the Nordic NRNs have proved to be able to give cost efficient services to research and education in the past, the safest road ahead is the continue to combine forces in NORDUnet. It will mean that total costs will continue to grow for some time yet, but distributed over the size of the user community served the cost will still compare favorably with other information technology expenses.