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With the growing size of distributed systems and the higher number of available resources and services in networks dynamical aspects become more and more important in systems engineering. We believe that there is a real need for decentral, self-organizing structures to cope with the upcoming challenges. In this paper we describe a framework which provides a self-organizing infrastructure that allows to link otherwise autonomous elements in a flexible way and adapts dynamically to changes in the underlying network. This framework is implemented as an extension of the mobile agent system Tracy, which is also a product of our university. The Tracy Domain Management module is part of the framework and provides the basis for segmenting the infrastructure. Another module we are going to discuss in this paper facilitates autonomous and proactive routing of mobile agents. Agents form the application layer of the system. Routing is triggered by the needs an agent inherits from its owner and then matched to the resources and services available in the network in an iterative fashion. We describe concepts, design issues and first results of our work with Tracy and the use of these additional Tracy modules.

This paper addresses some requirements of self-organizing networks as well as interoperability problems due to merges and splits phenomena. In a mobile environment, merges and splits characterize the spatial overlap between two self-organized networks. While merge refers to the time when two disjoint networks meet and overlap, split refers to the time of partition. In a dynamic environment, AutoComm (AC) principles bring a new support for interoperability since current protocol heterogeneity is observed at all stack layers from the radio interface to applications. In this paper, we reconsider the formalization of a community and its requirements. We then characterize the split and merge phenomena and their implications. We give some requirements that must fulfill solutions to merging (high context-awareness) in order for AC groups to self-scale. Finally, we propose a merging solution for overlapping wireless self-organized networks using heterogeneous routing protocols.

Autonomic behaviours in network operations will alleviate much of the labour intensive and error prone interventions of today’s complex networks. The Service Provider must be able to manage the infrastructure and services at an abstract level, focusing on what the desired behaviour should be rather than how it might be specifically achieved. Policy-Based Network Management () appears as one of the leading mechanisms to describe desired behaviours and abstract the programmability of an autonomic network infrastructure to the Service Provider. For massive-scale and complex networks, the current understanding of the Higher Level to Lower Level (HL→LL) refinement process commonly used in today is not completely effective. One problem encountered is the need to provide a bind mechanism between Higher Level and Lower Level policy specifications such that cross-layer policy requests in the policy continuum can be made by lower policy layers in a dynamic policy refinement cycle (LL→HL→LL). In this paper, we illustrate the problem with a policy-based simple admission control (SAC) application. We then show that policy specifications with a join operator (⋈) simplify the SAC specification. We also investigate the performance considerations of this enhancement in Internet size applications. Our future goal is to provide a policy inference engine that can support complex specifications appropriate for systems that support autonomic behaviours in large networks, made of Network elements with realistic memory and processing constraints.

Emerging distributed computing scenarios call for novel “autonomic” approaches to distributed systems development and management. In this position paper we analyze the distinguishing characteristics of those scenarios, discuss the inadequacy of traditional paradigms, and elaborate on primary role of “space” in modern distributed computing. In particular, we show that spatial abstractions promise to be basic necessary ingredients for a novel “spatial computing” paradigm, acting as a unifying framework for autonomic computing and communication. On this base, we propose a preliminary “spatial computing stack” to frame the key concepts and mechanisms of spatial computing. Eventually, we try to sketch a research agenda in the area.

To combat the increasing significance of deployment and configuration costs, the concept of a self-deploying, self-configuring radio access network is discussed. It is proposed that the basic sciences of complex systems (cellular automata, game theory, ecology modeling) can be exploited to design algorithms for such a system. An example, taken from the field of cellular automata, is presented for a network capable of self-adaptation to achieve universal radio coverage in a simplified environment.

Content Distribution has to date been addressed by a mix of centralized and uncoordinated distributed processes, such as server replication and traditional node caching mechanisms, respectively. It is an inherently distributed process that is also increasingly relying on entities that are not only increasingly distributed but also increasingly autonomous. Consequently, centralized – and typically targeting the “socially optimal” – decisions are rather unrealistic for a distributed environment of autonomic entities. Instead, a distributed management of the engaged autonomic entities, which take decisions dynamically, should be key to efficient content distribution. The latter is advocated in this paper in which two entities that are central to content distribution – specifically the content and the node storage – are considered and it is discussed how their autonomic behavior drives the operation of a content distribution network. In the first case, it is the content that manages itself by dynamically generating duplicate copies and pushing them to (seizing) the appropriate storage. In the second one, it is the node storage that is in charge, deciding on the content to be locally stored. The decisions taken by the distributed and autonomic entities may – in the extreme case – be driven by self-awareness and self-interest only, without any network state information and co-operativeness. Or, they may use (some) network information and take decisions in a more cooperative manner, despite their autonomic and self-interest-driven nature. An example is presented on the later case, showing the potential both social and individual benefits.

The Internet network technology today does not allow a sufficient degree of autonomy to express user choices, constraints and preferences in order to dynamically obtain the most suitable services. One of the goals of Autonomic Communication is to produce self-managing network elements able to provide the desired services in an automated way. In this context, we propose an architecture to automate user-provider and provider-provider relationships, by converting the Internet into an electronic market space where the commodities to be traded are network services. After an agreement has been reached via agent-based automated negotiation mechanisms, network elements must be automatically configured in order to enforce the agreed conditions. This is achieved by generating commands to programmable network elements via open interfaces. The ultimate goal is enable fully automatic installation, configuration and monitoring of protocols or service components involving multiple ownership domains, while taking into account the constraints and preferences of users and providers.

The Internet architecture is based on design principles such as end-to-end addressing and global routeability. It suits relatively static, well-managed and flat network hierarchies. Recent years have shown, however, that the Internet is evolving beyond what the current architecture can support. The Internet architecture struggles to support increasingly conflicting requirements from groups with competing interests, such as network, content and application service providers, or end-users of fixed, mobile and ad hoc access networks. This paper describes a new internetworking architecture, called TurfNet. It provides autonomy for individual network domains, or Turfs, through a novel inter-domain communication mechanism that does not require global network addressing or a common network protocol. By minimizing inter-domain dependencies, TurfNet provides a high degree of independence, which in turn facilitates autonomic communications. Allowing network domains to fully operate in isolation maximizes the scope of autonomic management functions. To accomplish this, TurfNet integrates the emerging concept of dynamic network composition with other recent architectural concepts such as decoupling locators from identifiers and establishing end-to-end communication across heterogeneous domains.

We describe the motivation and design of a novel embedded systems architecture for large networks of small devices, tha canonical example being wireless sensor networks. The architecture differs from previous work in being based explicitly on a hardware/software co-design approach centred around the deployment of novel programming language constructs directly onto hardware in order to improve optimisation and expressibility. The programming interface enables the dynamic download and execution of domain-specific code to facilitate the development of context aware pervasive computing systems whose behaviour must adapt to their changing environment. To this end, the architecture implements a virtual machine operating environment based on Scheme and Clinux that encapsulates a CPU core, digital logic, generic I/O, network interfaces and domain-specific programming language composition.

The VICOM (Virtual Immersive COMmunications) project is a three-year project funded by the Italian Ministry of Instruction University and Research aiming at investigating innovative communication paradigms. The project represents a wide coordinated effort focused on integration of immersive and wireless technologies in view of the fourth generation of mobile communications. The main goal of the project consists of the design of a wideband system architecture for immersive services and of its validation through two distributed large test-beds. Starting from VICOM ongoing experiences some future challenges and objectives for the future situated and autonomic communications technologies are envisaged in the paper.