Band 50, Heft 6

The Internet has become the main network technology supporting communications and Web services in all areas of our society. In order to perform this role efficiently, a fundamental redesign of the Internet architecture is being discussed. In particular, mobile devices and wireless access networks will constitute an important part of the Internet infrastructure. Based on a general discussion of requirements, this article focuses on the challenges of a next generation mobile Internet and discusses research approaches for mobility, addressing, heterogeneous access, and service platforms.

The enormous growth of bandwidth needs and the constant revenues of the carriers at the same time require the introduction of packet technologies in transport networks. The extension of Ethernet with carrier-grade features is a promising approach to provide necessary characteristics like scalability, quality of service, and operations, administration, and maintenance. Interesting technological aspects are multi-layer and multi-domain operation of these packet transport networks and their control via Generalized MPLS. A possible solution can be seen in a function split where IP stays the convergence platform for applications and services and Ethernet becomes the convergence platform for transport.

The fast increase of the routing table size in the default-free zone (DFZ) is a major concern for the scalability of the Internet and a threat for its effective operation in the future. Proposals exist to modify the current routing architecture in order to decelerate the growth of the routing tables in the DFZ, but they are difficult to deploy. The locator/identifier split (Loc/ID) principle is significantly different from routing and addressing in today´s Internet, but it is expected to improve routing scalability. We explain its basic idea, address interworking issues, point out design options, and review current implementation proposals.

Novel Internet applications demand global availability of complex services that can adapt dynamically to application requirements. At the same time, pervasive Internet usage and heterogeneous access technologies impose new challenges for service deployment. We present Spontaneous Virtual Networks (SpoVNet), a methodology that enables easy development of new services with transparent support for mobility, multi-homing, and heterogeneous environments. This article presents the overlay-based architecture of SpoVNet that supports the spontaneous deployment of new services as well as a seamless transition towards future networks. SpoVNet´s architecture offers support for the underlay aware adaptation of overlays by the use of cross-layer information. In the context of two exemplary services like a group communication service and an event service as well as two demanding applications – a realtime online game and a video streaming application – we illustrate how SpoVNet is of value in establishing services and applications for the Next Generation Internet.

The next generation Internet will not only be defined by its technological progress but also by innovative Internet applications which offer new features, more interactivity, and a better user experience. Structured overlay networks, which create a well-defined virtual topology above the basic transport network, are a powerful means to easily create such Internet applications. There are many different approaches to realize structured overlay networks which in their core functions share the same basic principles. In this work we summarize the fundamentals of structured overlay networks, describe their inherent problems, and present an overview of our solutions. We then show how all these ideas have been put into practice in terms of a distributed carrier grade communication platform.

The development of the Internet during the last years has shown that it becomes harder to integrate new functionality in order to fulfill the demands of new applications and the capabilities of new transport technologies. Especially the core mechanisms (TCP/IP) are hard to change. Thus the development of a new Internet architecture has been discussed for some time now. In this work we present a service-oriented approach for a new network architecture. At first it is argued which kinds of flexibility should be provided by an architecture. Then it will be shown which common principles of service-orientation support this flexibility. Further we present technical considerations for implementing network functionality by services.

The Internet today is an insecure place. New attacks and vulnerabilities emerge every day, user education remains fragmentary and security solutions are only sparsely deployed. Protecting networks against new and unexpected attacks remains a challenging task, given the dynamic nature of network traffic. It is difficult to model or predict what to consider as normal behavior in current and future networks, which is a pre-requisite for detecting deviations from normality. In this paper we argue that to cope with these challenges network protection has to become an integral part of future networks. The evolving research field on autonomic communication provides a basis for introducing techniques for detection and defense directly into network nodes. Together with integration of learning methods, we see deployment of cooperation strategies as the main enabler for self-protection.

Zusammenfassung Wer sich mit dem Computer näher beschäftigen muß, für den hat dieses Instrument viele Aspekte, und je mehr er davon kennen lernt, um so mehr neue tauchen vor ihm auf. Der Computer ist ein Instrument. Für viele Sparten. Dem einen Benützer dient er als Tischrechenmaschine mit einigen Gedächtnisfunktionen; jenem ist er ein Mittel, Differentialgleichungen wirklich zu lösen, von denen man vor 50 Jahren lediglich "bewies", daß sie überhaupt eine Lösung haben; anderen ist er eine Buchhaltung über unübersehbar viele Daten - praktisch liegt hier der größte Anwendungsbereich; und wieder anderen ist er ein Objekt philosophischer Betrachtung, das ihn herausfordert, über das Problem "Mensch" nachzudenken. Dem Techniker aber schließlich, der diese Gebilde baut, sind sie immerwährender Anlaß, sich mit der Natur auseinanderzusetzen, die da so vieles kann, was er auch können möchte.