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Integrating recent advancements in resilient algorithms and techniques into existing codes is a singular challenge in fault tolerance - in part due to the underlying complexity of implementing resilience in the first place, but also due to the difficulty introduced when integrating the functionality of a standalone new strategy with the preexisting resilience layers of an application. We propose that the answer is not to build integrated solutions for users, but runtimes designed to integrate into a larger comprehensive resilience system and thereby enable the necessary jump to multi-layered recovery. Our work designs, implements, and verifies one such comprehensive system of runtimes. Utilizing Fenix, a process resilience tool with integration into preexisting resilience systems as a design priority, we update Kokkos Resilience and the use pattern of VeloC to support application-level integration of resilience runtimes. Our work shows that designing integrable systems rather than integrated systems allows for user-designed optimization and upgrading of resilience techniques while maintaining the simplicity and performance of all-in-one resilience solutions. More application-specific choice in resilience strategies allows for better long-term flexibility, performance, and - importantly - simplicity.
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FORTIFY: Software Defined Data Plane Resilience
Given the scale and mission-critical nature of production networks today, it is essential to solidify their resilience to link failures. Building this resilience in each application separately is not scalable. In order to minimize downtime, at least some degree of resilience should be built directly into the data plane. Fast Failover groups in OpenFlow offer a mechanism to achieve this, but programming them introduces additional complexity to the existing arduous task of developing an SDN controller application. In this paper, we discuss how this complexity can be decoupled from the controller implementation. We introduce FORTIFY, a transparent resiliency layer that incorporates data plane fault tolerance into any existing controller application without any modification to it. FORTIFY operates as a shim layer between the controller and the data plane, and dynamically transforms the data plane rules computed by the controller to use Fast Failover groups. FORTIFY can be used off-The-shelf, or customized programmatically to choose specific types of backup paths. Experimental results collected on a production testbed demonstrate that FORTIFY is a practical, high-performance solution to data plane fault tolerance in SDNs.
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- Award ID(s):
- 2113819
- PAR ID:
- 10427017
- Editor(s):
- Larry Horner, Kurt Tutschku
- Date Published:
- Journal Name:
- 2022 IEEE Conference on Network Function Virtualization and Software Defined Networks, NFV-SDN 2022
- Page Range / eLocation ID:
- 6 to 12
- 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
- Conference Paper:
- https://doi.org/10.1109/NFV-SDN56302.2022.9974617
