Replicated Computations in a Distributed Switching Environment

Replication of computations in a distributed switching environment is studied. The first topics discussed are the requirements and the other design goals that have to be met by replicated computations in a distributed switching system. The requirements on the grade of service and availability performance objectives are largely set out in the international standards. A structured probability oriented software approach to building a kernel supporting replicated computations is suggested and the functional as well as the probability properties of the replication scheme are investigated. To aid the definition and investigation of the functional properties of the replication scheme a model of computation based on the actor model of Hewitt and Agha is defined and used. The overall replication scheme consists of a loose basic scheme, the real-time computation migration tools, here designated as warm-up algorithms, and the corrective replication tools augmenting the basic scheme. Language methods which enhance the transparency of the replication scheme are also discussed. The work has been done in connection with a redesign project of a distributed digital switching system and the results have largely been implemented in that environment

Program Leadership from a Nordic Perspective - Managing Education Development

Nordic Five Tech (N5T) is a strategic alliance between five technical universities in Denmark, Finland, Norway and Sweden. The overall aim is to “utilize shared and complementary strengths and create synergy within education, research and innovation”. In this paper we focus on university educational development issues by investigating the program leadership at five Nordic technical universities. Specifically, the paper compares definitions, views and experiences of education leadership in the Nordic Five Tech (N5T) universities. The paper does this by, first, reviewing the definitions of roles and responsibilities for program directors at each university, and second, by presenting results from a survey carried out in March 2012 among program directors at the N5T universities. Based on this data, we analyze how program directors experience their role, their possibilities to lead, and their opportunities of learning to lead. How is time for reflection and development as leaders handled at the different universities? The paper goes on to consider what impact the mandate of the leadership role has on the possibilities for developing educational programs. For instance, how can program directors ensure that learning objectives concerning generic skills and abilities are reached? How can program directors drive implementation of integrative and value-oriented topics such as sustainable development, innovation and entrepreneurship

6G network needs to support embedded trust

A slogan coined at the recent first Levi 6G Summit by Peter Wetter of Nokia Bell Labs was “the 6G is about the 6th sense”. This can be understood in at least two ways. One is that the network just knows what to do in all kinds of situations because of the use of AI and the second is that 6G radio will be widely used to sense the environment where the users are. In this view, 6G is seen as a continuation of the merge of the physical and the virtual words. An outcome of the Summit is a 6G White Paper documenting the ideas of some 60 invited people from the 300 participants about the future generation coming after 5G. This paper provides further discussion and justification of the trust and security aspects of the Networking Chapter in the White Paper. The paper focuses on principles and only refers to some verification in order not to clutter the discussion with technical detail. Opinions expressed here are of the author of this paper who was also the main editor of the Networking Chapter. The members of the White paper group on Networking or the editors of the White paper should not be held liable for the views expressed in the paper.Peer reviewe

Building MPLS VPNs with QoS Routing Capability

Recently MPLS is used for building up VPNs in IP backbone, called MPLS VPNs. In this paper, we discuss issues on finding routes with QoS requirements (i.e., QoS routing) in MPLS VPNs. We first present background on MPLS VPNs as well as QoS routing. Then we discuss both the benefits and problems resulted from introducing QoS routing into MPLS VPNs. We particularly present an architecture of MPLS VPNs with QoS routing capability, on which we discuss some important issues on running QoS routing in MPLS VPNs

Data plane protocols and fragmentation for 5G

Mobile networks up to this point have used general packet radio service (GPRS) tunneling protocol (GTP) in the core network. The fifth generation (5G) will be a major revolution in mobile networks and there have been discussions onto adopting a different protocol, with the proposals being generic routing encapsulation (GRE), virtual extensible local area network (VXLAN) and generic network virtualization encapsulation (Geneve). In this paper, these protocols are compared. GTP has a 32-bit tunnel endpoint identifier (TEID) and runs on top of user datagram protocol (UDP), thus allowing many applications in the same IP address in different ports. However, GTP unnecessarily stores packet length many times in the Internet protocol (IP), UDP and GTP levels, and the fragmentation strategy defined in third generation partnership project (3GPP) specifications is suboptimal. GRE has well-defined fragmentation strategy but runs directly on top of IP, so multiplexing based on ports is not possible. VXLAN and Geneve have only 24 bits for network identifier and encapsulate media access control (MAC) frames, which is not really what is needed here, and the fragmentation strategy of VXLAN is suboptimal albeit in a different way than in GTP. In this paper, we propose a common fragmentation strategy that may be applicable to all protocols.Peer reviewe