Lefteris Mamatas

Monitoring virtual networks with Lattice

The use of the Lattice monitoring framework as a fundamental part of a overlay management system for virtual networks is presented. Lattice has been specially designed for monitoring resources and services in virtualized environments, including virtual networks. Monitoring of virtualized resources and services has many criteria which are not relevant for monitoring systems that are used for traditional fixed resources. We present the main aspects of the framework together with details of measurement transmission and meta-data encoding. Finally, the use of the Lattice framework for monitoring virtual machines executing under hypervisor control is presented.

On the Selection of Management/Monitoring Nodes in Highly Dynamic Networks

This paper addresses the problem of provisioning management/monitoring nodes within highly dynamic network environments, particularly virtual networks. In a network, where nodes and links may be spontaneously created and destroyed (perhaps rapidly) there is a need for stable and responsive management and monitoring, which does not create a large load (in terms of traffic or processing) for the system. A subset of nodes has to be chosen for management/monitoring, each of which will manage a subset of the nodes in the network. A new, simple, and locally optimal greedy algorithm called Pressure is provided for choice of node position to minimize traffic. This algorithm is combined with a system for predicting the lifespan of nodes, and a tunable parameter is also given so that a system operator could express a preference for elected nodes to be chosen to reduce traffic, to be stable,” or some compromise between these positions. The combined algorithm called PressureTime is lightweight and could be run in a distributed manner. The resulting algorithms are tested both in simulation and in a testbed environment of virtual routers. They perform well, both at reducing traffic and at choosing long lifespan nodes.

Softwarization of Future Networks and Services -Programmable Enabled Networks as Next Generation Software Defined Networks

The Software Defined Networks (SDNs) and Network Functions Virtualisation (NFVs), as recent separate research and development trends have the roots in programmable / active network technologies and standards developed a decade ago. In particular, they are associated with the decoupling of forwarding from control and hardware from networking software, using open interfaces to connectivity resources. The next phase of R&D would involve novel integration and use of all connectivity, storage and processing resources under new management interacting with control systems for provisioning of on-demand networking and services with continuous update of features. This brings into focus a relatively new and key topics for the next decade: what and how to create the conditions for effective and continuous updating and changing the networking functions without reinventing each time architectural aspects and related components (e.g. Softwarization of Future Networks and Services or Programmable Enabled Networks). This paper presents motivation, architecture and the key challenges in realising such programmable enabled networks as the next generation Software Defined Networks focusing on its management plane.

Self-organising Management Overlays for Future Internet Services

Networks are becoming service-aware implying that all relevant business goals pertaining to a service are fulfilled, and also the network resources are used optimally. Future Internet Networks (FIN) have time varying topology (e.g. such networks are envisaged in Autonomic Internet [1], FIND program [2], GENI program [3], FIRE program [4], Ambient Networks [5], Ad-hoc networks [6]) and service availability and service context change as nodes join and leave the networks. In this paper we propose and evaluate a new self-organising service management system that manages such changes known as the Overlay Management Backbones (OMBs). The OMB is a self-organising solution to the problem space in which each OMB node is dynamically assigned a different service context task. The selection of OMB nodes is conducted automatically, without the need of relatively heavy-weighted dynamic negotiations. Our solution relies on the scalability and dynamicity advantages of Distributed Hash Tables (DHTs). This system is needed to select continuously, automatically, and dynamically a set of network nodes, to become responsible for collecting the availability information of service context in the changing network. This solution advances the state of the art avoiding dynamic negotiations between all network nodes reducing management complexity and cost for bandwidth-limited environments.

Platforms and Software Systems for an Autonomic Internet

The current Internet does not enable easy introduction and deployment of new network technologies and services. This paper aims to progress the Future Internet (FI) by introduction of a service composition and execution environment that re-use existing components of access and core networks. This paper presents essential service-centric platforms and software systems that have been developed with the aim to create a flexible environment for an Autonomic Internet

CA-RTO: a contention-adaptive retransmission timeout

We show that TCP timers, based solely on RTT estimations and measurements, cannot capture with precision the level of flow contention. We notice that increased contention may stabilize RTT variation, minimize the deviation and, in turn, shorten the timeout. We show that this behavior is undesirable indeed, since it leads to unfair resource utilization. We propose CA-RTO, an algorithm that incorporates a contention parameter and a randomization technique into the retransmission timeout. We report significant improvement in fairness, great reduction of retransmitted packets and slight improvements in application goodput.

A service-aware virtualized software-defined infrastructure

The Internet infrastructure is gradually improving its flexibility and adaptability due to the incorporation of new promising technologies, such as the software-defined networks and the network function virtualization. The main goal is to meet the diverse communication needs of the users, while the global system operation satisfies the business and societal goals of the infrastructure and service providers. This calls for solutions that consider both local and global network viewpoints and provide sophisticated system control in a stable and predictable way, while being service-aware. We propose a fully integrated solution along these lines: the VLSP, a service-aware software-defined infrastructure for networks and clouds. The VLSP consists of three main distributed systems: a facility performing uniformly logically-centralized management and control of the infrastructure, called the virtual infrastructure management; an information management infrastructure able to maintain an accurate view of the infrastructure environment at both the local and system levels, called the virtual infrastructure information service; and a lightweight virtualization hypervisor able to perform configuration changes in the infrastructure resources, called the lightweight network hypervisor. We discuss representative use-case scenarios, while we demonstrate how VLSP tunes performance trade-offs for particular service demands.

Towards an Information Management Overlay for emerging networks

There has recently been an increasing research interest in network management infrastructures that autonomously adapt to the dynamics of the environment. In this paper, we present an information management platform, called the Information Management Overlay (IMO), which is an infrastructure that regulates information flow based on the properties and the state of the network environment. We discuss the design, implementation and optimization issues of this platform and we investigate experimentally how the IMO can adapt to different settings and optimization requirements.

Information Exchange Management as a Service for Network Function Virtualization Environments

The Internet landscape is gradually adopting new communication paradigms characterized by flexibility and adaptability to the resource constraints and service requirements, including network function virtualization (NFV), software-defined networks, and various virtualization and network slicing technologies. These approaches need to be realized from multiple management and network entities exchanging information between each other. We propose a novel information exchange management as a service facility as an extension to ETSIs NFV management and orchestration framework, namely the virtual infrastructure information service (VIS). VIS is characterized by the following properties: 1) it exhibits the dynamic characteristics of such network paradigms; 2) it supports information flow establishment, operation, and optimization; and 3) it provides a logically centralized control of the established information flows with respect to the diverse demands of the entities exchanging information elements. Our proposal addresses the information exchange management requirements of NFV environments and is information-model agnostic. This paper includes an experimental analysis of its main functional and non-functional characteristics.

Software Enabled Future Internet – Challenges in Orchestrating the Future Internet

This position paper presents SoftINTERNET an initiative for a service-aware and management-aware network control infrastructure for heterogeneous networks (i.e., wired and wireless) that uses software driven features for the elaboration, development, and validation of networking concepts. The proposed infrastructure aims to optimally integrate the connectivity and management layers. It operates across multiple network environments and on top of private and public network clouds utilising fixed and mobile virtual resources, OpenFlow enabled network devices like switches and routers, and networks of Smart Objects. In this position paper, we discuss the motivation, architecture and research challenges for such a promising concept.