iDSRT: Integrated Dynamic Soft Real-Time Architecture for Critical Infrastructure Data Delivery over WLAN

  • Hoang Nguyen
  • Raoul Rivas
  • Klara Nahrstedt
Part of the Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering book series (LNICST, volume 22)


The real-time control data delivery system of the Critical Infrastructure (i.e. SCADA - Supervisory Control and Data Acquisition system) is important because appropriate decisions cannot be made without having data delivered in a timely manner. Because these applications use multiple heterogeneous resources such as CPU, network bandwidth and storage, they call for an integrated and coordinated real-time scheduling across multiple resources to meet end-to-end deadlines. We present a design and implementation of iDSRT - an integrated dynamic soft real-time system to provide fine-grained end-to-end delay guarantees over WLAN. iDSRT takes the deadline partitioning approach: end-to-end deadlines are partitioned into multiple sub-deadlines for CPU scheduling and network scheduling. It integrates three important schedulers: task scheduler, packet scheduler and node scheduler to achieve global coordination. We validate iDSRT in Linux and evaluate it in an experimental SCADA test-bed. The results are promising and show that iDSRT can successfully achieve soft real-time guarantees in SCADA system with very low packet loss rate compared to available commodity best-effort systems.


Multi-resource scheduling Quality-of-service WLAN 


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Copyright information

© ICST Institute for Computer Science, Social Informatics and Telecommunications Engineering 2009

Authors and Affiliations

  • Hoang Nguyen
    • 1
  • Raoul Rivas
    • 1
  • Klara Nahrstedt
    • 1
  1. 1.University of Illinois at Urbana-ChampaignUrbanaUSA

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