1. WoPANets: Decision-support Tool for real-time Networks Design
Ahlem Mifdaoui
Innovation IT Day

2. Context & Motivations Increasing complexity of real-time networks:
Mixed-criticality data delivery
Multi-hop real-time communication
Heterogeneous architecture
Large-scale networks
Cyclic dependencies at the communication level
Deterministic guarantees of temporal and hardware constraints are of the utmost importance
Choosing the right network’s parameters respecting the system constraints becomes a difficult task for designer

3. Context & Motivations
An accurate timing verification approach is needed to guarantee the network requirements, since the first steps of the design cycle
System-level performance analysis
The designer need to choose the right system’s parameters before investing too much time in detailed implementations
A new decision-support tool, WoPANets (Worst Case Performance Analysis of Embedded Networks)
Enhancing the design process time and costs of real-time networks

4. Related Work Overview
The design space exploration approaches for real-time systems are mainly focused on the SW/HW Partitioning/ Mapping issues and generally:
Simplify the communication network by considering an arbitrary maximum delay bound
Ignore completely the communication issue
However,
Integrating the accurate design of the communication network with the SW/HW partitioning will clearly enhance the system performance

5. Outline Introduction Performance Analysis Methodology Applications
Decision-support Tool
Conclusions & Key Perspectives

6. Timing Verification Approach
Need an accurate verification approach to handle
Worst-case behavior to fulfill certification requirements
Scalability requirements
Simple to conduct
Tight results
Existing approaches
Simulation-based: simulating the entire system leads to high complexity and limited efficiency
Analytical-based: various existing approaches to analyze the worst-case behavior
The most relevant is Network Calculus used for the AFDX certification

7. Performance optimization
Methodology overview
Specification
#step1
System Modeling
#step2
Performance analysis
#step3
Performance optimization
#step4
Refinement
#step5

8. Outline Introduction Performance Analysis Methodology Applications
Decision-support Tool
Conclusions & Key Perspectives

9. Real-Time Networks AFDX standard for avionics
Most common Real-Time Ethernet profiles for automation and automotive
Spacewire for satellites
Network On Chip for the Many-core Architecture …

10. Outline Introduction Performance Analysis Methodology Applications
Decision-support Tool: WoPANets
Conclusions & Key Perspectives

11. Decision-support tool WoPANets (1)
Worst-case Performance Analysis of embedded Networks
Performs a system level performance evaluation based on NC
Certification requirements
Includes an optimization process for design space exploration
Enhance the design process time and costs
Compatibility with existent conception approaches (UML, AADL)
Easy to use within design cycle
Integrate high level models of the most common real-time networks
Easy to use by any designer without any specific knowledge of the used analytical formalism due to an ergonomic GUI
Modular and Easy to extend

12. Decision-support tool WoPANets (2)
Palette
Analysis & Optimization
Flow/Node Properties
Results

13. Decision-support tool WoPANets (3)
Related projects
ANR Emergence 2012 (WoPANets), Valorisation projects with Airbus Group and ESA (under submission)
Publications
Mifdaoui, Ahlem and Ayed, Hamdi “WOPANets: a tool for WOrst case performance analysis of embedded networks”. In: International Workshop on Computer-Aided Modeling Analysis and Design of Communication Links and Networks (CAMAD), Dec 2010, Miami, United States.
Apvrille, Ludovic and Saqui-Sannes, Pierre de and Mifdaoui, Ahlem “A UML framework for the dimensioning and formal verification of embedded systems”. In: SAFA Annual Workshop on Formal Methods (SAFA 2009), 23 Sept 2009, Sophia-Antipolis, France.

14. Conclusions
System level Worst case performance analysis becomes a necessity to avoid introducing errors at the first steps of the design cycle
Enhance the design process time and costs
A decision-support tool WoPANets is available to be used by industrial designers of real-time networks

15. Thanks for your attention Questions?