The NEMO Basic Support (NEMO BS) protocol provides a technique for enabling entire networks of IPv6 hosts to gain Internet access and remain reachable via constant, unaltered addresses whilst their underlying location in the Internet changes. In addition to individual hosts, this NEMO model also supports entire mobile networks connecting to other mobile networks, resulting in topologies known as Nested NEMO networks. In this paper we explain the inefficiencies that arise if NEMO BS is used to support this type of scenario and introduce our NEMO+ suite of protocols which are designed to optimise performance in Nested NEMO networks. We detail the Tree Discovery (TD), Network In Node Advertisement (NINA) and Reverse Routing Header (RRH) protocols that make up the NEMO+ suite and provide experimental evaluation results from a testbed comprising of our two distinct protocol implementation platforms (Linux and Cisco IOS). In addition we present simulation results based on scenarios of mass deployment of NEMO+ enabled mobile networks in order to determine the feasibility of our approach to efficiently support Nested NEMO networks.

The NEMO Basic Support protocol is a Home Agent based technique (derived from Mobile IPv6) that permits the mobility of a network of IPv6 devices to be supported through the use of a dedicated Mobile Router. This NEMO Mobile Router accepts connections from IPv6 nodes and transparently manages any IP mobility on their behalf, which means that as well as individual hosts, a NEMO Mobile Router can also accept connections from other NEMO mobile networks. When this occurs, the inter-connected NEMO mobile networks form a highly inefficient topology known as a Nested NEMO network. In this paper we describe this concept and examine the properties of Nested NEMO networks. In particular we highlight how their communication patterns differ from typical Mobile Ad hoc Networks (MANET) and present example scenarios which demonstrate their potential application domain. We present the Unified MANEMO Architecture (UMA), a solution which has been developed in order to efficiently support these Nested NEMO scenarios. Through varying experimental testbed configurations, we provide an evaluation of the protocols performance and demonstrate how our approach is able to be deployed over the current Internet architecture without requiring any augmentation to access networks or the core Internet infrastructure.

Abstract. The diverse characteristics of network anomalies and the different recovery approaches that can subsequently be employed to remediate their effects, constitute static defence mechanisms tuned at responding to specific abnormalities suboptimal for providing an overall resilience framework. The emerging autonomic network environments in particular, require always-on, adaptive, and generic mechanisms that can integrate with the core networking infrastructure and provide for a range of self-* capabilities, ranging from selfprotection to self-tuning. In this paper we present the design and implementation of an adaptive remediation component built on top of an autonomic network node architecture [2]. A set of pluggable modules that employ diverse algorithms and explicit cross-layer interaction have been engineered to mitigate different classes of anomalous traffic behaviour in response to both legitimate and malicious external stimuli. In collaboration with an always-on measurement-based anomaly detection component, our prototype empowers the properties of self-optimisation and self-healing.

Abstract-Workflows are widely used in applications that require coordinated use of computational resources. Workflow definition languages typically abstract over some aspects of the way in which a workflow is to be executed, such as the level of parallelism to be used or the physical resources to be deployed. As a result, a workflow management system has responsibility for establishing how best to map tasks within a workflow to the available resources. As workflows are typically run over shared resources, and thus face unpredictable and changing resource capabilties, there may be benefit to be derived from adapting the task-to-resource mapping while a workflow is executing. This paper describes the use of utility functions to express the relative merits of alternative mappings; in essence, a utility function can be used to give a score to a candidate mapping, and the exploration of alternative mappings can be cast as an optimization problem. In this approach, changing the utility function allows adaptations to be carried out with a view to meeting different objectives. The contributions of this paper include: (i) a description of how adaptive workflow execution can be expressed as an optimization problem where the objective of the adaptation is to maximize some property expressed as a utility function; (ii) a description of how the approach has been applied to support adaptive workflow execution in grids; and (iii) an experimental evaluation of the resulting approach for alternative utility measures based on response time and profit.

The infrastructure of the modern Internet has become a complex mesh of varying network types. A single network protocol cannot optimally support every underlying technology and the diverse nature of these networks places increasing strain on the concept of running IP over everything and everything over IP. The introduction of new protocols and services also forces network administrators to employ techniques such as tunneling to ensure end-to-end IP connectivity. Unfortunately these techniques inherently require some form of efficiency trade-off and are not an ideal long term solution.To address these issues, this paper proposes a new network layer protocol, NP++, which uses a level of indirection between the logical and physical specifications of the protocol. NP++ also enables the protocol to automatically configure which physical mapping is used over a link with no direct input from the user. This allows the protocol to change its transmission characteristics depending on the type of underlying network while presenting a unified view to the upper layers. This ensures a higher level of flexibility along with the potential to increase efficiency. The implementation of the NP++ prototype is also demonstrated with a view to encouraging its use when researching next generation Internet technologies.