ing WS1S Systems to Verify Parameterized Networks . . . . . . . . . . . . 188 Kai Baukus, Saddek Bensalem, Yassine Lakhnech and Karsten Stahl FMona: A Tool for Expressing Validation Techniques over Infinite State Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 J.-P. Bodeveix and M. Filali Transitive Closures of Regular Relations for Verifying Infinite-State Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220 Bengt Jonsson and Marcus Nilsson Diagnostic and Test Generation Using Static Analysis to Improve Automatic Test Generation . . . . . . . . . . . . . 235 Marius Bozga, Jean-Claude Fernandez and Lucian Ghirvu Efficient Diagnostic Generation for Boolean Equation Systems . . . . . . . . . . . . 251 Radu Mateescu Efficient Model-Checking Compositional State Space Generation with Partial Order Reductions for Asynchronous Communicating Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 Jean-Pierre Krimm and Laurent Mounier Checking for CFFD-Preorder with Tester Processes . . . . . . . . . . . . . . . . . . . . . . . 283 Juhana Helovuo and Antti Valmari Fair Bisimulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299 Thomas A. Henzinger and Sriram K. Rajamani Integrating Low Level Symmetries into Reachability Analysis . . . . . . . . . . . . . 315 Karsten Schmidt Model-Checking Tools Model Checking Support for the ASM High-Level Language . . . . . . . . . . . . . . 331 Giuseppe Del Castillo and Kirsten Winter Table of

Tools and Algorithms for the Construction and Analysis of Systems. Proc. TACAS 2009

To support bursty traffic on the Internet (and especially WWW) efficiently, optical burst switching (OBS) is proposed as a way to streamline both protocols and hardware in building the future gener...

Optical burst switching (OBS) - a new paradigm for an optical Internet

A Comprehensive Survey of Network Function Virtualization

Middleboxes or network appliances like firewalls, proxies, and WAN optimizers have become an integral part of today's ISP and enterprise networks. Middlebox functionalities are usually deployed on expensive and proprietary hardware that require trained personnel for deployment and maintenance. Middleboxes contribute significantly to a network's capital and operational costs. In addition, organizations often require their traffic to pass through a specific sequence of middleboxes for compliance with security and performance policies. This makes the middlebox deployment and maintenance tasks even more complicated. Network Function Virtualization (NFV) is an emerging and promising technology that is envisioned to overcome these challenges. It proposes to move packet processing from dedicated hardware middleboxes to software running on commodity servers. In NFV terminology, software middleboxes are referred to as Virtual Network Functions (VNFs). It is a challenging problem to determine the required number and placement of VNFs that optimize network operational costs and utilization, without violating service level agreements. We call this the VNF Orchestration Problem (VNF-OP) and provide an Integer Linear Programming (ILP) formulation with implementation in CPLEX. We also provide a dynamic programming based heuristic to solve larger instances of VNF-OP. Trace driven simulations on real-world network topologies demonstrate that the heuristic can provide solutions that are within 1.3 times of the optimal solution. Our experiments suggest that a VNF based approach can provide more than 4 χ reduction in the operational cost of a network.

/pdf/on-orchestrating-virtual-network-functions-1s6qxqlu5y.pdf

On orchestrating virtual network functions

Information-Centric Networking (ICN) is a new networking paradigm, which replaces the widely used host-centric networking paradigm in communication networks (e.g., Internet, mobile ad hoc networks) with an information-centric paradigm, which prioritizes the delivery of named content, oblivious of the contents origin. Content and client security are more intrinsic in the ICN paradigm versus the current host centric paradigm where they have been instrumented as an after thought. By design, the ICN paradigm inherently supports several security and privacy features, such as provenance and identity privacy, which are still not effectively available in the host-centric paradigm. However, given its nascency, the ICN paradigm has several open security and privacy concerns, some that existed in the old paradigm, and some new and unique. In this article, we survey the existing literature in security and privacy research sub-space in ICN. More specifically, we explore three broad areas: security threats, privacy risks, and access control enforcement mechanisms. 
We present the underlying principle of the existing works, discuss the drawbacks of the proposed approaches, and explore potential future research directions. In the broad area of security, we review attack scenarios, such as denial of service, cache pollution, and content poisoning. In the broad area of privacy, we discuss user privacy and anonymity, name and signature privacy, and content privacy. ICN's feature of ubiquitous caching introduces a major challenge for access control enforcement that requires special attention. In this broad area, we review existing access control mechanisms including encryption-based, attribute-based, session-based, and proxy re-encryption-based access control schemes. We conclude the survey with lessons learned and scope for future work.

Security, Privacy, and Access Control in Information-Centric Networking: A Survey

Content Centric Networking represents a paradigm shift in the evolution and definition of modern network protocols. Many research efforts have been made with the purpose of proving the feasibility and the scalability of this proposal. Our main contribution is to provide an analysis of the Pending Interest Table memory requirements in real deployment scenarios, especially considering the impact of distributed denial of service attacks. In fact, the state that the protocol maintains for each resource request makes the routers more prone to resources exhaustion issues than in traditional stateless solutions. Our results are derived by using a full custom simulator and considering the different node architectures that have been proposed as valid reference models. The main outcomes point out differentiated weaknesses in each architecture we investigated and underline the need for improvements in terms of security and scalability.

/pdf/pit-overload-analysis-in-content-centric-networks-2ogdr8nvem.pdf

PIT overload analysis in content centric networks

The recent growth of IoT devices, along with edge computing, has revealed many opportunities for novel applications. Among them, Unmanned Aerial Vehicles (UAVs), which are deployed for surveillance and environmental monitoring, are attracting increasing attention. In this context, typical solutions must deal with events that may change the state of the network, providing a service that continuously maintains a high level of performance. In this paper, we address this problem by proposing a distributed architecture that leverages a Multi-Agent Reinforcement Learning (MARL) technique to dynamically offload tasks from UAVs to the edge cloud. Nodes of the system co-operate to jointly minimize the overall latency perceived by the user and the energy usage on UAVs by continuously learning from the environment the best action, which entails the decision of offloading and, in this case, the best transmission technology, i.e., Wi-Fi or cellular. Results validate our distributed architecture and show the effectiveness of the approach in reaching the above targets.

Sustainable Task Offloading in UAV Networks via Multi-Agent Reinforcement Learning

In April 2018, under the auspices of the POR-FESR 2014-2020 program of Italian Piedmont Region, the Turin's Centre on High-Performance Computing for Artificial Intelligence (HPC4AI) was funded with a capital investment of 4.5M€ and it began its deployment. HPC4AI aims to facilitate scientific research and engineering in the areas of Artificial Intelligence and Big Data Analytics. HPC4AI will specifically focus on methods for the on-demand provisioning of AI and BDA Cloud services to the regional and national industrial community, which includes the large regional ecosystem of Small-Medium Enterprises (SMEs) active in many different sectors such as automotive, aerospace, mechatronics, manufacturing, health and agrifood.

/pdf/hpc4ai-an-ai-on-demand-federated-platform-endeavour-4c0o776l19.pdf

HPC4AI: an AI-on-demand federated platform endeavour

The role of software and its flexibility is becoming more and more important in todays networks. New emerging paradigms, such as Software Defined Networking (SDN) and Network Function Virtualization (NFV), are changing the rules of the game, shifting the focus on dynamicity and programmability. Perfectly aligned with this new spirit, the FP7 UNIFY European project aims at realizing this appealing vision by applying DevOps concepts to telecom operator networks and supporting the idea of fast network reconfiguration. However, the increased range of possibilities offered by the DevOps approach comes at the cost of designing new processes and toolkits to make SDN and NFV a concrete opportunity. In this paper we specifically focus on the verification process as part of the challenging tasks that must be addressed in this scenario and its fundamental role of automatically checking some desired network properties before deploying a particular configuration. Our preliminary results confirm the feasibility of the approach and encourage future efforts in this direction.

/pdf/formal-verification-of-virtual-network-function-graphs-in-an-48avbbr1xe.pdf

Formal Verification of Virtual Network Function Graphs in an SP-DevOps Context

The deployment of wireless technologies in industrial networks is very promising mainly due to their inherent flexibility. However, current wireless solutions lack the capability to provide the deterministic, low delay service required by many industrial applications. Moreover, the high level of interference generated by industrial equipment limits the coverage that ensures acceptable performance. Multihop solutions, when combining frame forwarding with higher node density, have the potential to provide the needed coverage while keeping radio communication range short. However, in multihop solutions, the medium access time at each of the nodes traversed additively contributes to the end-to-end delay and the forwarding delay (i.e., the time required for packets to be processed, switched, and queued) at each node is to be added as well. This paper describes time-driven access and forwarding, a solution for guaranteeing deterministic delay, at both the access and forwarding level, in wireless multihop networks, analyzes its properties, and assesses its performance in industrial scenarios.

Guido Marchetto

Papers

PIT overload analysis in content centric networks

Sustainable Task Offloading in UAV Networks via Multi-Agent Reinforcement Learning

HPC4AI: an AI-on-demand federated platform endeavour

Formal Verification of Virtual Network Function Graphs in an SP-DevOps Context

Time-Driven Access and Forwarding for Industrial Wireless Multihop Networks