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The supervisory control and data acquisition (SCADA) network in a smart grid requires to be reliable and efficient to transmit real-time data to the controller. Introducing SDN into a SCADA network helps in deploying novel grid control operations, as well as, their management. As the overall network cannot be transformed to have only SDN-enabled devices overnight because of budget constraints, a systematic deployment methodology is needed. In this work, we present a framework, named SDNSynth, that can design a hybrid network consisting of both legacy forwarding devices and programmable SDN-enabled switches. The design satisfies the resiliency requirements of the SCADA network, which are specified with respect to a set of identified threat vectors. The deployment plan primarily includes the best placements of the SDN-enabled switches. The plan may include one or more links to be installed newly. We model and implement the SDNSynth framework that includes the satisfaction of several requirements and constraints involved in the resilient operation of the SCADA. It uses satisfiability modulo theories (SMT) for encoding the synthesis model and solving it. We demonstrate SDNSynth on a case study and evaluate its performance on different synthetic SCADA systems.
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The Cost on System Performance of Requirements on Differentiable Variables
Abstract System design is commonly thought of as a process of maximizing a design objective subject to constraints, among which are the system requirements. Given system-level requirements, a convenient management approach is to disaggregate the system into subsystems and to “flowdown” the system-level requirements to the subsystem or lower levels. We note, however, that requirements truly are constraints, and they typically impose a penalty on system performance. Furthermore, disaggregation of the system-level requirements into the flowdown requirements creates added sets of constraints, all of which have the potential to impose further penalties on overall system performance. This is a highly undesirable effect of an otherwise beneficial system design management process. This article derives conditions that may be imposed on the flowdown requirements to assure that they do not penalize overall system performance beyond the system-level requirement.
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- Award ID(s):
- 1923164
- PAR ID:
- 10328130
- Date Published:
- Journal Name:
- Journal of Mechanical Design
- Volume:
- 143
- Issue:
- 5
- ISSN:
- 1050-0472
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1115/1.4049336
