Distributed applications and interoperable systems : 21st IFIP WG 6.1 International Conference, DAIS 2021 : Held as part of the 16th International Federated Conference on Distributed Computing Techniques, DisCoTec 2021, Valletta, Malta, June 14-18, 2021 :

This book constitutes the refereed proceedings of the 21st IFIP WG 6.1 International Conference on Distributed Applications and Interoperable Systems, DAIS 2021, held in Valletta, Malta, in June 2021, as part of the 16th International Federated Conference on Distributed Computing Techniques, DisCoTec 2021. The 7 regular papers and 3 short papers presented in this book were carefully reviewed and selected from 15 submissions. DAIS addresses all practical and conceptual aspects of distributed applications, including their design, modeling, implementation and operation, the supporting middleware, appropriate software engineering methodologies and tools, as well as experimental studies and applications. Foreword Preface Organization iExec: Building a Decentralized, Trusted and Privacy-Preserving Computing Infrastructure (Invited Speaker) Contents Cloud and Fog Computing A Methodology for Tenant Migration in Legacy Shared-Table Multi-tenant Applications 1 Introduction 2 A Method for Tenant Migration 2.1 Design Goals 2.2 Overview 2.3 Mapping Tables to Tenant or Reference DB 2.4 Migration of a Tenant 3 Case Studies 3.1 Iomad 3.2 Camunda 4 Evaluation 4.1 Experimental Setup 4.2 Results 5 Related Work 6 Conclusion References Network Federation for Inter-cloud Operations 1 Introduction 2 Related Work 3 Tunnel Protocols 3.1 Forwarding 3.2 Performance 3.3 Security 3.4 Configuration Complexity 3.5 Network Multiplexing 3.6 Conclusion 4 Approach 4.1 Operation Modes 4.2 Internal Networking 4.3 Deployment 5 Evaluation 5.1 Functionality 5.2 Security 5.3 Performance 6 Conclusion References SpecK: Composition of Stream Processing Applications over Fog Environments 1 Introduction 2 Related Work 3 SpecK: An SPE Coordinator 3.1 Targeted Platform 3.2 SpecK Usage 3.3 SpecK Architecture and Internals 4 Experiments 4.1 Scalability and Overhead 4.2 Edge-to-Cloud Deployment 5 Conclusion References Fault Tolerance and Big Data ASPAS: As Secure as Possible Available Systems 1 Introduction 2 Related Work 3 ASPAS Protocol 3.1 Problem 3.2 System and Fault Models 3.3 An Overview of ASPAS 3.4 Normal Operation Phase 3.5 Certification Phase 3.6 ASPAS Mechanisms 4 Evaluation 4.1 Implementation 4.2 Experimental Settings 4.3 Evaluation Methodology 4.4 Latency and Throughput Microbenchmarks 4.5 Scalability with YCSB Benchmark 5 Conclusion References Portable Intermediate Representation for Efficient Big Data Analytics 1 Introduction 2 Design and Challenges 2.1 Design Objectives 3 System Architecture 3.1 Intermediate Representation Model 3.2 Runtime Environment 3.3 Backend Compiler 3.4 Serverless Containers 4 Related Work 5 Conclusion References Distributed Algorithms Shared-Dining: Broadcasting Secret Shares Using Dining-Cryptographers Groups 1 Introduction 2 Background 2.1 Notation and Scenario 2.2 Dining-Cryptographers Protocol 2.3 Shamir's Secret Sharing 2.4 Goal 3 Secret-Shared Dining-Cryptographers Protocol 3.1 Correctness 4 Security and Privacy Evaluation 4.1 Goal 4.2 Semi-Honest Model 4.3 Outside Observers 4.4 Modern DC Malicious Mitigations 5 Performance Evaluation 5.1 Methodology 5.2 Message Size l 5.3 Network Size n 5.4 Network Delay 5.5 Number of Shares k 6 Applications 7 Conclusion References UCBFed: Using Reinforcement Learning Method to Tackle the Federated Optimization Problem 1 Introduction 2 Related Work 2.1 Federated Learning 2.2 Multi-armed Bandit Problem 3 The Proposed UCBFed Algorithm 3.1 Cosine Distance Weight (CDW) 3.2 Reward Allocation 3.3 Clients Selection and Model Aggregating 4 Experiments 4.1 Experiments Details 4.2 Experiment Results 5 Conclusion and Future Works References Trusted Environments KeVlar-Tz: A Secure Cache for Arm TrustZone 1 Introduction 2 Background 3 Motivating Scenarios 3.1 Digital Health 3.2 Smart Building Management 4 Architecture 5 Implementation 5.1 KeVlar-Tz Trusted Application 6 Evaluation 6.1 Micro-benchmarks 6.2 Macro-benchmark: Digital Health 7 Related Work 8 Conclusion and Future Work References Analysis and Improvement of Heterogeneous Hardware Support in Docker Images 1 Introduction 2 Background 2.1 Processors and Hardware Heterogeneity 2.2 Docker Images 3 Methodology 4 Evaluation 4.1 Results 4.2 Augmented Metadata 4.3 Improved Container Image Tooling 5 Discussion 6 Related Work 7 Conclusion and Future Work References Invited Paper Simulation of Large Scale Computational Ecosystems with Alchemist: A Tutorial 1 Introduction 2 A Meta-model of Computational Ecosystems 2.1 Abstract Meta-model 2.2 Executable Models: Incarnations 3 Guided Examples 3.1 The YAML-Based Simulation Specification Language 3.2 Three Connected Devices 3.3 A Grid of Devices Playing Dodgeball 3.4 A Gradient on a Grid of Devices 3.5 Arbitrary Network Graphs 3.6 Node Mobility and Indoor Environments 3.7 Real-World Maps and GPS Traces 4 In-Depth Analysis of Simulated Scenarios 5 Concluding Remarks References Author Index