Information and Communication Technology

Flow and fantastic experience with tomorrow's computer network

By Ragnhild Krogvig Karlsen
January 29, 2007

Our communication society places high demands on the security and quality of network services. How long will we accept poor image quality or delayed transfer during video conferences? When the network is used for web TV or radio broadcasting, we want the best possible sound and image quality. We must be able to trust Internet banking services and know that the information transfer is secure. Network services ought to work when we need them.


Research at Q2S will provide improved quality of service in tomorrow’s packed switch networks. Audio, images, emails, encrypted documents and other information are sent over the Internet as a series of digital packets. This principle makes the network traffic flexible and provides flow, but the more advanced and diverse the network technology and services get, the more the world of information on the network grows in size and complexity, and the greater the challenges of securing the quality of service – i.e. accessibility, product quality, and security. This is very relevant for wireless networks and small, portable units that are becoming increasingly more common.

Research at Q2S ranges from projects with wireless networks, optical networks, format standardization, network architecture, and logistics for traffic flow and tracking information packets on the network, to protection against computer crime. Work also includes multimedia over IP, sound quality on video conferences and image quality of films over the network.

Applying for a patent for unique HASH algorithms
Among other things, the Centre has developed a test-bed which enables experiments with different ways of handling and transferring high-quality audio and video streams over the network. Streaming servers and clients, a simulator and an IP network simulator are connected and function as a digital laboratory. Here researchers can perform very accurate measurements and get an overview of the network traffic and the image and audio quality.

Q2S recently presented the first version of LDAS, a program used to research multimedia interaction, such as two musicians playing together over the Internet. The aim is to find methods of transmitting high-quality multi-channel audio with the least possible delay.

In 2005, Q2S filed a provisional patent application for unique HASH algorithms. In cooperation with the University of Santa Barbara, California, researchers at Q2S have developed tools and a new method of analysing and securing evidence of computer crime.


Next Generation Internet – architecture that workschild listening Q2S is part of the European research network Euro NGI which cooperates on improved quality of service, increased reliability, and improved operation in the next generation Internet. In the future network, the diversity of formats with audio, images, film, and multimedia will flow in real time, and that requires new technological solutions, including new protocols. 

Protocols are standardized sets of rules that govern how computers communicate with each other and exchange data over the network. They have to be so good that they obtain the leading position. The Internet was in its early days created in the moment that one particular protocol (called IP today) was used by enough people so that it could be called a network.

The major question is which technological solutions will win the next generation. ”We are in the middle of an evolution,” said Professor Peder J. Emstad. In 2006, researchers at Q2S have published several articles in the Computer Networks journal. The articles present thorough analyses of methods to secure digital documents as well as suggestions about new mathematical methods of calculation to dimension the network.

According to the Science Citation Index, the article written by Jiang Yuming “Delay bound and packet scale rate guarantee for some expedited forwarding networks” has gained a major response.


Sorting the wheat from the chaff
Commercial producers of ICT have mixed interests. For this reason independent research at a high level plays an important part in deciding which programs, file types and systems actually work the best. It is all about researching to find stable solutions and develop new standards with the best possible quality.

”We are working on theoretical problems, and we primarily conduct fundamental research,” says professors Knapskog and Emstad.

A large amount of the practical research at Q2S is based on simulations and the Centre has some heavy simulators for controlled laboratory experiments at its disposal.

two men playing guitarGreat sound and lifelike voices
In 2005, the audio laboratory Aura was commissioned and is now used both for simulations and authentic sense and perception experiments with people in the studio. If you open the door, you can hear flamenco rhythms or find yourself in the middle of an intense jam session over the Internet. Tones, tempo, depth and substance similar to that of a CD are ideal, but heavy when transmitted over the network. Q2S have investigated how large the delays in audio transmission can be before it affects the harmonization.

”The communication between musicians becomes poorer when the sound is delayed by more than 30 milliseconds. When we speak, we seem to be less fine-tuned, though. A conversation on the mobile works just fine even though the delay can be as much as 150 milliseconds,” says Professor Peter Svensson.

The transmission over the network is not the only thing moving slowly. The compression and packing of information related to sending and receiving are associated with the problems that Q2S maps and solves.

How heavy is the best sound?
Such an acoustic laboratory equipped with instruments that can recreate distinct sound through 16 loudspeakers that enables experiments to be done with multi-channel recordings. This involves the use of software for audio processing especially designed for advanced audio communication and real-time virtual acoustics.

Q2S is also starting experiments with 3D sound. Most people have experienced such sound in cinemas, and sometimes with computer games on surround systems at home. In the future we may expect even better sound. Q2S primarily researches signal processing, but this includes both music technology and psychology when working with audio and image communication.

Simulators and live networksPeople at Q2S More than 200 research and educational institutions in Norway are connected to the research network UNINETT which cooperates with Q2S. This network provides a unique opportunity to test theories and research results in a live network in full operation.

UNINETT runs networks and network services for universities, university colleges and research institutions in Norway, and carries out major national ICT tasks. It operates Norway’s top domains (.no) and is responsible for high-performance computing in projects requiring extreme computing capacity, such as meteorology and astronomy. In other words, UNINETT has a high level of activity and provides great opportunities to find out how new technology works. Researchers study the network traffic, test how we can trace lost information packets, or study security networks in difficult situations.

Information security with encryption and elegant algorithms
Computer network security involves three important principles: Confidentiality, integrity, and accessibility. In practice, nobody should be able to listen to other people’s activities on the network, but the wireless technology makes the networks more open. At the same time, there is an increase in the use of small terminals (mobile phones and PDAs) that are unable to process heavy encryption. Q2S researchers find new algorithms for encryption by calculation, and strive to make them faster and more secure. Classic encryption deals with distorting text and computer encryption involves much of the same: the binary codes that constitute the files, are distorted. This is what the algorithms are used for.

Patent for digital fingerprints
Q2S has filed a provisional patent application for a different type of algorithms known as HASH functions. If you are worried that your computer might be infected with a virus, you can run HASH algorithms on it to reveal if anyone has broken into your computer and caused problems. HASH algorithms find the content of files and make a ‘fingerprint’ of it – a small string of data that functions as a representation of the file. The problem is that today's HASH algorithms are not sufficiently secure, because they do not provide a clear extract, but make prints that could be mistaken for other files. The Q2S algorithms create prints that are more accurate and unique.

Revealing computer crime by a new tool to secure evidence
”In the fight against computer crime we also study methods and tools that the police could use to secure evidence of attacks and break-ins,” says Professor Knapskog, who is in charge of several security projects. Through their cooperation with the University of Santa Barbara, researchers at Q2S have developed models of complex network systems and found ways of reconstructing situations and events following attacks on company networks.

Researchers at Q2S participate in international workshops on HASH functions arranged by NIST – National Institute of Science of Technology, Washington – and NSA – National Security Agency, Santa Barbara, and results have been presented at the most key international conferences on information security and cryptography, such as Crypto which is arranged annually in Santa Barbara, California.

International cooperation
“It is important that we attract international researchers and research fellows. Even though the research environment here in Norway is quite large, the field we work on is complex and developments happen so fast that international networks and cooperation are essential,” said Peter Emstad. As often as possible, Q2S sends its doctoral candidates to international seminars, workshops and conferences, and hosts international experts itself.

“The more people thinking and exchanging information and knowledge, the better,” Emstad concludes.


Centre for Quantifiable Quality of Service in Communication Systems (Q2S)

Q2S conducts fundamental research to solve problems related to security and quality in information technology, primarily within net-based services provided over IP. Society’s dependency on these services is growing, but very often the quality is poor and there is a lack of security.

Host institution:
Norwegian University of Science and Technology (NTNU)

Research Centre Director:
Professor Svein J. Knapskog, NTNU

Nils Holme (Chairman)
Pro-Rector Astrid Lægreid, NTNU
Professor Jostein Grepstad, IME, NTNU
Chief of Research Rolf Bjørn Haugen, TELENOR ASA
Chief Executive Officer Petter Kongshaug, UNINETT AS

5 professors (NTNU), 6 post-docs, 18 PhD candidates, UNINETT: Chief Executive Officer, Director of Experimental Networks, 2 researchers.

International partners:
EuroNGI, NoE, COST, EU projects Geant 2, SCAMPI and LOBSTER

Norwegian partner:

Contact details:
Centre for Quantifiable Quality of Service in Communication Systems
Centre of Excellence
O.S. Bragstads plass 2E
NO-7491 Trondheim

Tel:(+47) 73 55 17 28
Fax: (+47) 73 59 27 90

Office address:
Room E-253
Electrical Engineering Building
O.S. Bragstads plass 2E
NTNU Gløshaugen,
Trondheim, Norway

Budget 2006:
NOK 26.79 million/Euro 3.1 million/USD 3.9 million

Centre of Excellence
Q2S was established as a Centre of Excellence (CoE) in 2003.

The establishment involves five years upgraded and intensive research activities with a potential prolongation until 2013. The annual allocation from the Research Council of Norway of NOK 11 million contributes to a long-term and intensive perspective on the research. This effort will stimulate innovative research that will yield scientific results at a high international level.