*Please note the following update:* 1) Deadline extended: *May 10th* 2) ISCC PEDISWESA workshop will be held online and the Accepted Papers will be published in IEEExplore if the authors provide a presentation and/or a video. The registration fees will be reduced as follows: - Workshop Author Member Fee: *100 Euros* - Workshop Authors Non-Member Fee: *125 Euros* *12th IEEE Workshop on Performance Evaluation of Communications in Distributed Systems and Web-based Service Architectures PEDISWESA* http://www.xanalytics.ca/pediswesa2020/index.html *in conjunction with IEEE Symposium on Computers and Communications (ISCC 2020)* https://conferences.imt-atlantique.fr/iscc2020/ *JULY 7TH - 10TH, 2020 – RENNES, FRANCE* Performance evaluation is still a topic that attains a lot of attention in both distributed and mobile systems as well as Web based services architectures. Due to the recent advances in internet-based applications as well as distributed and mobile communication systems, we are witnessing a variety of new technologies. However, these systems are becoming very large and complex at the same time. Several challenges remain to be resolved before these systems become a commodity. Guaranteeing QoS and provisioning of web-based systems as well as distributed and mobile systems and evaluating their communication performance represent among the challenging problem in the design of these systems. Quantitative analysis can be very difficult and may be intractable because of the state space explosion. New methods and tools have recently emerged for these kinds of complex systems, such as Stochastic Automata Networks, Stochastic bounds, PEPA, etc. This workshop focuses on the performance evaluation of both distributed and mobile systems, as well as Web based services architectures using both analytical methods and simulation studies. Authors are encouraged to submit full papers presenting new research related to QoS and communication performance evaluation of these systems. Submitted papers must not have been published elsewhere nor currently be under review by another conference or journal. *Topics of interest include* (but are not limited to): - Routing optimization - Quantitative analysis - Stochastic comparisons - Bandwidth management - Web services composition - Measurement, analysis, modeling - QoS for Web services architectures - Simulation and measurements techniques - Tools and software for performance evaluation - Network Protocols design for Web service devices - Performance evaluation of distributed and web-based systems - Communication performance evaluation of distributed and mobile systems - Performance of Blockchain - Performance evaluation of Vehicular networks - Connected and Autonomous Vehicles *Committee* General Chair: - Lynda Mokdad, University Paris XII, France Steering Committee: - Lynda Mokdad, University Paris XII, France - Jalel Ben-Othman, University of Paris, France Technical Program Co-Chairs: - Moayad Aloqaily, xAnalytics Inc., Ottawa, Canada - Abd-Elhamid M. Taha, Alfaisal University, KSA *Important Dates* - Paper submission deadline: *May 10th, 2020* - Notification of paper acceptance: May 20th, 2020 - Submission of camera-ready papers: May 30th, 2020