The looming depletion of the public IPv4 address space has recently inspired a number of proposals intended to work around the inevitable address shortage. Broadly, all of these can be classified as address sharing, tunneling and translation mechanisms. While IPv6 is the proper solution to the problem as it simply makes more addresses available, the deployment hurdles of IPv6 make it questionable whether it will be universally available once the IPv4 address pool runs out. In this paper we focus on one of these solutions, namely A+P, that allocates a "fraction" of an IP address to end hosts by restricting the usable port range. We compare a number of strategies to use and reuse port numbers. Based on data from an ISP's access line serving nearly 7000 residential broadband customers these strategies are analyzed. To this end, we performed a hypothetical optimization exercise to find the optimal number of customers that can share a single IPv4 address.

In this paper, we describe the approaches taken in the 4WARD project to address the challenges of the network of the future. Our main hypothesis is that the Future Internet must allow for the fast creation of diverse network designs and paradigms, and must also support their co-existence at run-time. We observe that a pure evolutionary path from the current Internet design will not be able to address, in a satisfactory manner, major issues like the handling of mobile users, information access and delivery, wide area sensor network applications, high management complexity, and malicious traffic that hamper network performance already today. Moreover, the Internet’s focus on interconnecting hosts and delivering bits has to be replaced by a more holistic vision of a network of information and content. This is a natural evolution of scope requiring nonetheless a re-design of the architecture. We describe how 4WARD directs research on network virtualisation, novel InNetworkManagement, a generic path concept, and an information centric approach, into a single framework for a diversified, but interoperable, network of the future.

SPam over Internet Telephony (SPIT) is expected to become a very serious issue in the next years. The threat is going to spin out from the well known email spam problem by bot nets being re-programmed to initiate not just spam emails but also Voice over IP (VoIP) calls. Preventing SPIT is a new problem, because many well-established methods for blocking email spam cannot be applied. Currently, several SPIT prevention methods are being proposed but SPIT prevention research is still at a very early stage. In this paper, we propose an innovative way to detect SPIT calls by comparing applying hidden Turing tests that compare them with typical human communication patterns. For passing these tests, significant resource consumptions at the SPIT generating bot nets would be required which contradicts the spammer's objective of placing as many SPIT calls as possible, The proposed method has several advantages compared to other methods that also interact with the caller. We validated its feasibility with a prototype implementation that we integrated into our modular VoIP security system called VoIP SEAL.

The Internet is currently evolving beyond what its architecture can support. Often, the mechanisms that allow the Internet to adapt to increasingly conflicting sets of new requirements break some of its basic design principles and can thus severely interfere with end-toend communication. This paper recognizes that increased autonomy of network regions is a key requirement for future internetworking. It outlines a new internetworking architecture that enables interoperation among a set of autonomous, heterogeneous network domains. The architecture is based on a global identity space and does not require global addressing or a shared internetworking protocol. It integrates the new concept of dynamic network composition with other recent architectural concepts, such as decoupling locators from identifiers. 1.

The development of future releases of third generation and fourth generation cellular network shows a clear indications that today's ATM-based radio access network (RAN) was replaced by an IP-based RAN particularly for reducing the cost compared to today's RANs. Managing an IP-based RAN with SNMP is a challenge, particularly concerning scalability. Already existing solutions for delegating management functions to managed nodes can achieve the required scalability, but they come with a big overhead of resource consumption and complexity. This paper presents a lean solution for health checking of managed nodes that achieves this goal by restricting itself to this purpose. The CHECK MIB module serves for remote configuration of heath check actions to be performed at a managed node and for retrieving health check results. Resource consumption is very low compared to already existing, more general technologies. Health checks can be specified easily by setting a very small number of objects and the implementation of the MIB module is lightweight.

The Internet is currently evolving beyond what its architecture can support. Often, the mechanisms that allow the Internet to adapt to increasingly conflicting sets of new requirements break some of its basic design principles and can thus severely interfere with end-to-end communication. This paper recognizes that increased autonomy of network regions is a key requirement for future internetworking. It outlines a new internetworking architecture that enables interoperation among a set of autonomous, heterogeneous network domains. The architecture is based on a global identity space and does not require global addressing or a shared internetworking protocol. It integrates the new concept of dynamic network composition with other recent architectural concepts, such as decoupling locators from identifiers.

The IETF has developed several specifications for policy-based configuration management. In addition, an infrastructure for distributed management by delegation has been specified. This paper combines key concepts developed in these two efforts and proposes a policy-based configuration management architecture built upon the distributed management infrastructure. Two prototype implementations for managing Differentiated Services are discussed and evaluated.

Multi-protocol label switching (MPLS) is in the process of standardization by the Internet Engineering Task Force (IETF). It is regarded as a technology for traffic engineering and QoS in IP-networks. In this paper, we address the management of MPLS networks, which is crucial for large networks. We decided to follow the IETF Policy Framework approach and extended the common information model (CIM) for policies with MPLS specific classes. MPLS introduces the notion of a label switched path (LSP), possibly covering an entire network, which calls for an extension of the IETF Policy Framework into the direction of network and service management issues. We address this by preparing a three-level policy architecture including managing on device, network, and service level using policies. However, the main focus of the paper is the management of MPLS with network-level policies. We describe a prototypical implementation of a policy-based management system for MPLS, operating on network elements represented in a network simulator.

The joint Jasmin project of the Technical University of Braunschweig and NEC C&C Research Laboratories is concerned with the development, implementation and practical evaluation of the management by delegation architecture standardized by the Distributed Management (DISMAN) working group of the IETF. This paper presents the open source software components that have been developed over two years within the Jasmin project, namely the Jasmin DISMAN-SCRIPT-MIB SNMP agent with its Java and Tcl runtime engines, a Java package for higher level operations on the DISMAN-SCRIPT-MIB and DISMAN-SCHEDULE-MIB agents, a Java GUI application for interacting with DISMAN-SCRIPT-MIB agents, a Java AgentX sub-agent toolkit that simplifies the development of scripts exporting new MIB objects, a package that facilitates the development of monitoring scripts, and a DISMAN-SCHEDULE-MIB sub-agent. Besides describing the software components and their relations, we also present some project history and experiences specific to open source software development.

Scalable and efficient management of today's fast growing networks requires distributed management systems. This paper introduces a classification of distributed management systems, followed by an overview of technologies for building such systems. One technology, the IETF Script MIB, is discussed in detail, including an implementation architecture and performance studies. Finally, application scenarios are presented, demonstrating how distributed management applications can be built by means of the IETF Script MIB.

This paper discusses the security aspects of the IETF Script MIB which integrates the management by delegation model into the Internet management framework. The paper shows how SNMPv3 security mechanisms have been utilized to protect the Script MIB from unauthorized access. This paper also describes the security aspects of a prototype implementation which uses the Java virtual machine as a runtime system for delegated management functions.

A modification of Kohonen's (1982) self-organizing feature maps offers solutions for a wide range of graph mapping problems. This is reached by replacing the Euclidian metric of the target space by a new metric. A sample implementation for mapping parallel programs onto processor networks demonstrates the properties of this method.