Policy-based management is based on defining a set of global rules, according to which a network or distributed system must operate. In the last few years, policy-based management has begun to emerge as the dominant paradigm for developing network and systems management functions, primarily, since it can reduce complexity in management applications. Although attempts are underway to standardize policy-based management, significant research challenges remain. At KTH and SICS, a joint activity has been started to focus on some of the key issues. The paper outlines the research agenda for this activity.

If quality of service could be provided at the transport or the application layer, then it might be deployed simply by software upgrades, instead of requiring a complete upgrade of the network infrastructure. In this paper, we propose a self-admission control scheme that does not require any network support or external monitoring schemes. We apply the admission control scheme to IP telephony as it is an important application benefiting from admission control. We predict the quality of the call by observing the packet loss over a short initial period using an in-band probing mechanism. The quality prediction is then used by the application to continue or to abort the call. Using over 9500 global IP telephony measurements, we show that it is possible to accurately predict the quality of a call. Early rejection of sessions has the advantage of saving valuable network resources plus not disturbing the on-going calls.

The PROMPT project has resulted in a great number of second cycle courses for professionals in software engineering and development. It has also led to an accumulation of learning experiences regarding the offering of such courses online. This report summarizes the learnings that project partner RISE has made and its contributions towards the common project goal of establishing a catalog of continuous-education courses for Swedish software industry. We report on how courses should be designed and conducted. The experience is that a clear structure and set of goals is needed, with teaching that activates the participants and supports retention. Professional training may require different formats for given contents to suit both part-time students as well as those who quickly want to learn full-time. Online education requires good system support and we summarize the experiences from Scalable Learning, a tool provided by RISE, which can inform other system providers of useful functionality. We end with a look at design exercises for the future of technical universities.

There has been much attention given to ATM Adaptation Layers (AAL) over the ten-year history of ATM standardization. Yet none of the existing standards include a retransmission protocol to ensure reliability of the transfers. In this paper we propose an AAL for doing selective retransmissions of individual segments that have been lost or corrupted in the transfer. Since the amount of retransmitted data equals the amount lost, there is little risk of aggravating congestion and the reliability is provided as economically as possible, which is a virtue for low-capacity radio links. The protocol relies on the orderly delivery of ATM virtual circuits so that data octets can be identified uniquely by their location in the data stream.

Video transfers across IP and ATM networks have received much research attention during the last ten years. Various video services are expected in the future, enabled by the rapid development in video coding and broadband network technology. This paper gives an introduction to the issues involved in asynchronous video transfers. Brief overviews of video coding, rate control, multiplexing, as well as delay, error and loss control are given.

The research on traffic control has not yet lead to a consensus on how to properly allocate resources in ATM networks. There are consequently no practicable methods available now when the initial deployment of ATM switches and terminals is under way. Yet, many of the applications which motivate the deployment uses multi-media and will thus require some degree of performance guarantees on the information transfer. Here we suggest a readily applicable method for reserving capacity in ATM networks. Cells using the reserved capacity may only depart at fixed time-instances, and have reserved buffers in the network nodes. The scheme gives a lossless performance, can be implemented with low complexity; it simplifies the call-acceptance and allows ``best effort'' traffic to use slack in the reserved and all of the non-reserved capacity.

Cybercampus Sweden is a national initiative to provide education, research, innovation and advice in cybersecurity and cyber-defense. This brochure addresses needs for cybersecurity training and education: There is a manifest imbalance between the cybersecurity workforce required in Sweden and the number of skilled graduates being produced by Swedish universities. There is also a gap between the needed cybersecurity skillset and the contents of existing education programs. For these reasons, Cybercampus Sweden aims at building capacity for work force training and to facilitate new cross-university cybersecurity programs, taking advantage of the specific teaching and research expertise from different universities. These comprise bachelor-level programs that provide a strong base with deep technical knowledge, and master-level and continuous education programs that train the cybersecurity workforce needed in Swedish organizations through applied and advanced courses with direct contact to ongoing research.

Time, day, location and instantaneous network conditions largely dictate the quality of Voice over IP calls. In this paper we present the results of over 18000 VoIP measurements, taken from nine sites connected in a full-mesh configuration. We measure the quality of the routes on a hourly basis by transmitting a pre-recorded call between a pair of sites. We repeat the procedure for all nine sites during the one hour interval. Based on the obtained jitter, delay and loss values as defined in RFC 1889 (RTP) we conclude that the VoIP quality is acceptable for all but one of the nine sites we tested. We also conclude that VoIP quality has improved marginally since we last conducted a similar study in 1998.