Distributed Real-time Systems with Ethernet

Distributed real-time systems require predictable networks to exchange application data within bounded delays. Switched Ethernet is an attractive networking technology for distributed real-time systems. However, Ethernet devices require special coordination mechanisms to support real-time traffic because of their inherent competitive approach. Embedding coordination units in the network interfaces is a common approach to prevent competition. While hardware scheduling units can operate at line rate with predictable delays at the end-stations, frame processing tasks and buffer management in standard switches introduce high latency and jitter in the path, preventing accurate synchronization between distributed stations.

This project is about:

  • Enabling real-time capabilities on top of standard Ethernet
  • Deriving efficient application-specific schedules for distributed real-time applications
  • Investigating flexibility in the context of safety-critical applications

By intersecting research on formal models and abstractions for dynamic-TDMA arbitration and technological insights of modern reconfigurable architectures, we have developed a comprehensive open-source framework that tackles multiple open challenges in heterogeneous distributed systems, including provision of ultra-low latency and jitter, dynamic bandwidth management, and segmentation of real-time domains within large networks.

The complete framework, including source code for hardware components and software tools, and a detailed description of illustrative examples of the achieved properties in multi-hop Ethernet setting are available on the demonstrator page.

Project members: 
Faculty
Graduate student
Postdoctoral Fellow
Visiting graduate student
Visiting graduate student
Last updated: February 29, 2016

Related Publications

Azim, A., G. Carvajal, R. Pellizzoni, and S. Fischmeister, "Generation of Communication Schedules for Multi-Mode Distributed Real-Time Applications", Proceedings of Design, Automation and Test in Europe (DATE), Grenoble, France, pp. 1--6, March, 2014. PDF icon [paper] (1.21 MB)
Carvajal, G., and S. Fischmeister, "An Open Platform for Mixed-Criticality Real-time Ethernet", Proc. of the Conference on Design, Automation and Test in Europe (DATE), Grenoble, France, pp. 153-156, 2013. PDF icon [paper] (425.47 KB)
Carvajal, G., M. Figueroa, R. Trausmuth, and S. Fischmeister, "Atacama: An Open FPGA-based Platform for Mixed-Criticality Communication in Multi-segmented Ethernet Networks", Proc. of the 21st IEEE International Symposium on Field-Programmable Custom Computing Machines (FCCM), pp. 121--128, April, 2013. PDF icon [paper] (1.26 MB)
Carvajal, G., and S. Fischmeister, "A TDMA Ethernet Switch for Dynamic Real-Time Communication", Proc. of the 18th IEEE Symposium on Field-Programmable Custom Computing Machines (FCCM), Charlotte, United States, pp. 119–126, May, 2010. PDF icon [paper] (292.42 KB)
Weiss, G., S. Fischmeister, M. Anand, and R. Alur, "Specification and Analysis of Network Resource Requirements of Control Systems", Proc. of the 12th International Conference on Hybrid Systems: Computation and Control (HSCC), Los Angeles, USA CA, pp. 381–395, April, 2009. PDF icon [paper] (252.55 KB)
Fischmeister, S., and R. Trausmuth, "A Programmable Arbitration Layer For Adaptive Real-Time Systems", Proc. of the Intl. Workshop on Adaptive and Reconfigurable Embedded Systems (APRES), St. Luis, USA, pp. 27–31, April, 2008.
Almeida, L., M. Anand, S. Fischmeister, and I. Lee, "A Dynamic Scheduling Approach to Designing Flexible Safety-Critical Systems", Proc. of the 7th Annual ACM Conference on Embedded Software (EMSOFT), Salzburg, Austria, pp. 67--74, October, 2007. PDF icon [paper] (302.29 KB)
Anand, M., S. Fischmeister, and I. Lee, "Composition Techniques for Tree Communication Schedules", Proc. of the 19th Euromicro Conference on Real-Time Systems (ECRTS), Pisa, Italy, pp. 235–246, July, 2007. PDF icon [paper] (698.16 KB)
Anand, M., S. Fischmeister, and I. Lee, "An Analysis Framework for Network-Code Programs", Proc. of the ACM & IEEE International Conference on Embedded Software (EMSOFT), Seoul, South Korea, pp. 122–131, October, 2006. PDF icon [paper] (494.91 KB)
Fischmeister, S., O. Sokolsky, and I. Lee, "Network-Code Machine: Programmable Real-Time Communication Schedules", Proc. of the IEEE Real-Time and Embedded Technology and Applications Symposium (RTAS), San Jose, USA, pp. 311–324, April, 2006. PDF icon [paper] (232.2 KB)
Anand, M., S. Fischmeister, J. Kim, and I. Lee, "Distributed Code Generation from Hybrid Systems Models for Time-delayed Multirate Systems", Proc. of the ACM Conference on Embedded Software (EMSOFT), New York, USA, pp. 210–213, September, 2005. PDF icon [paper] (320.51 KB)
Carvajal, G., L. Araneda, A. Wolf, M. Figueroa, and S. Fischmeister, "Integrating Dynamic-TDMA Communication Channels into COTS Ethernet Networks", IEEE Transactions on Industrial Informatics, vol. 12, issue 5, pp. 1806-1816, 2016.
Carvajal, G., C. W. Wallace Wu, and S. Fischmeister, "Evaluation of Communication Architectures for Switched Real-time Ethernet", IEEE Transactions on Computers, 2012.
Anand, M., S. Fischmeister, I. Lee, and L. T. X. Phan, "State-based scheduling with tree schedules: analysis and evaluation", Real-Time Systems, vol. 48, issue 4, pp. 430 - 462, 2012. PDF icon [paper] (1.24 MB)
Anand, M., S. Fischmeister, Y. Hur, J. Kim, and I. Lee, "Generating Reliable Code from Hybrid-Systems Models", IEEE Transactions on Computers, vol. 59, pp. 1281–1294, July, 2010. PDF icon [paper] (1.91 MB)
Fischmeister, S., R. Trausmuth, and I. Lee, "Hardware Acceleration for Conditional State-Based Communication Scheduling on Real-Time Ethernet", IEEE Transactions on Industrial Informatics, vol. 5, pp. 325–337, 2009. PDF icon [paper] (1.23 MB)
Arney, D., S. Fischmeister, J. M. Goldman, I. Lee, and R. Trausmuth, "Plug-and-Play for Medical Devices: Experiences from a Case Study", Biomedical Instrumentation & Technology, vol. 43, 2009. PDF icon [paper] (530.32 KB)
Fischmeister, S., O. Sokolsky, and I. Lee, "A Verifiable Language for Programming Real-Time Communication Schedules", IEEE Transactions on Computers, vol. 56, issue 11, pp. 1505 - 1519, 11/2007. PDF icon [paper] (1.39 MB)