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Despite recent advances, guaranteeing the correctness of large-scale distributed applications without compromising performance remains a challenging problem. Network and node failures are inevitable and, for some applications, careful control over how they are handled is essential. Unfortunately, existing approaches either completely hide these failures behind an atomic state machine replication (SMR) interface, or expose all of the network-level details, sacrificing atomicity. We propose a novel, compositional, atomic distributed object (ADO) model for strongly consistent distributed systems that combines the best of both options. The object-oriented API abstracts over protocol-specific details and decouples high-level correctness reasoning from implementation choices. At the same time, it intentionally exposes an abstract view of certain key distributed failure cases, thus allowing for more fine-grained control over them than SMR-like models. We demonstrate that proving properties even of composite distributed systems can be straightforward with our Coq verification framework, Advert, thanks to the ADO model. We also show that a variety of common protocols including multi-Paxos and Chain Replication refine the ADO semantics, which allows one to freely choose among them for an application's implementation without modifying ADO-level correctness proofs.
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Cresco: A distributed agent-based edge computing framework
The Cresco distributed agent-based framework is designed to address the challenges of edge computing. We present an actor-model implementation for the management of large numbers of geographically distributed services, comprised from heterogeneous resources and communication protocols, in support of low-latency realtime streaming applications. We present the purpose of our work, the basic methodology, the initial results already obtained, the relationship to the existing software, and the potential of the presently implemented framework to a number of potential further projects that could be developed on the basis of the existing implementation.
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- Award ID(s):
- 1450937
- PAR ID:
- 10098887
- Date Published:
- Journal Name:
- 2016 12th International Conference on Network and Service Management (CNSM)
- Page Range / eLocation ID:
- 400 to 405
- 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/CNSM.2016.7818455
