Aneris: A Mechanised Logic for Modular Reasoning about Distributed Systems

AbstractBuilding network-connected programs and distributed systems is a powerful way to provide scalability and availability in a digital, always-connected era. However, with great power comes great complexity. Reasoning about distributed systems is well-known to be difficult. In this paper we present , a novel framework based on separation logic supporting modular, node-local reasoning about concurrent and distributed systems. The logic is higher-order, concurrent, with higher-order store and network sockets, and is fully mechanized in the Coq proof assistant. We use our framework to verify an implementation of a load balancer that uses multi-threading to distribute load amongst multiple servers and an implementation of the two-phase-commit protocol with a replicated logging service as a client. The two examples certify that is well-suited for both horizontal and vertical modular reasoning.

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Gobra: Modular Specification and Verification of Go Programs

Computer Aided Verification - Lecture Notes in Computer Science ◽

10.1007/978-3-030-81685-8_17 ◽

2021 ◽

pp. 367-379

Author(s):

Felix A. Wolf ◽

Linard Arquint ◽

Martin Clochard ◽

Wytse Oortwijn ◽

João C. Pereira ◽

...

Keyword(s):

Distributed Systems ◽

Programming Language ◽

Message Passing ◽

Safety Data ◽

Separation Logic ◽

Data Race ◽

Static Verification ◽

Crash Safety ◽

Concurrent And Distributed Systems ◽

Systems Programming

AbstractGo is an increasingly-popular systems programming language targeting, especially, concurrent and distributed systems. Go differentiates itself from other imperative languages by offering structural subtyping and lightweight concurrency through goroutines with message-passing communication. This combination of features poses interesting challenges for static verification, most prominently the combination of a mutable heap and advanced concurrency primitives.We present Gobra, a modular, deductive program verifier for Go that proves memory safety, crash safety, data-race freedom, and user-provided specifications. Gobra is based on separation logic and supports a large subset of Go. Its implementation translates an annotated Go program into the Viper intermediate verification language and uses an existing SMT-based verification backend to compute and discharge proof obligations.

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Distributed causal memory: modular specification and verification in higher-order distributed separation logic

Proceedings of the ACM on Programming Languages ◽

10.1145/3434323 ◽

2021 ◽

Vol 5 (POPL) ◽

pp. 1-29

Author(s):

Léon Gondelman ◽

Simon Oddershede Gregersen ◽

Abel Nieto ◽

Amin Timany ◽

Lars Birkedal

Keyword(s):

Higher Order ◽

Separation Logic ◽

Specification And Verification

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Semantics of Separation-Logic Typing and Higher-Order Frame Rules

20th Annual IEEE Symposium on Logic in Computer Science (LICS' 05) ◽

10.1109/lics.2005.47 ◽

2006 ◽

Cited By ~ 14

Author(s):

L. Birkedal ◽

N. Torp-Smith ◽

Hongseok Yang

Keyword(s):

Higher Order ◽

Separation Logic

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Two-phase flow in porous media with multicomponent transport: Formulation and higher order numerical solution

Journal of Computational Physics ◽

10.1016/0021-9991(89)90193-9 ◽

1989 ◽

Vol 84 (1) ◽

pp. 255

Author(s):

Lawrence J. Roberts

Keyword(s):

Porous Media ◽

Numerical Solution ◽

Two Phase Flow ◽

Higher Order ◽

Flow In Porous Media ◽

Phase Flow ◽

Two Phase ◽

Multicomponent Transport

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FROUDE’S LAW OF SIMILITUDE – CONTEMPORARY AND FUTURE SEAKEEPING TESTING

The International Journal of Maritime Engineering ◽

10.5750/ijme.v153ia2.849 ◽

2021 ◽

Vol 153 (A2) ◽

Author(s):

R P Dallinga ◽

R H M Huijsmans

Keyword(s):

Model Test ◽

Scale Effects ◽

Higher Order ◽

Air Pressure ◽

Test Results ◽

Viscous Effects ◽

Two Phase ◽

Scale Models ◽

Non Linear

Historically “scale effects” in the interpretation of tests with scale models in waves using Froude’s Law of Similitude are mostly associated with viscous effects. Nowadays, with a much more complete modelling of reality and a focus on higher order non-linear phenomena, scaling of model test results implies a wider range of assumptions than the validity of Froude’s Law. Our contribution to the conference is a visionary review of contemporary and future problems in the interpretation of these tests. In this context we will discuss the developments in test techniques, including the development of a new Two-Phase Laboratory facilitating seakeeping and sloshing tests at reduced air pressure.

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Verification and Validation of Concurrent and Distributed Systems (Track Summary)

Leveraging Applications of Formal Methods, Verification and Validation: Verification Principles - Lecture Notes in Computer Science ◽

10.1007/978-3-030-61362-4_24 ◽

2020 ◽

pp. 421-425

Author(s):

Marieke Huisman ◽

Cristina Seceleanu

Keyword(s):

Distributed Systems ◽

Verification And Validation ◽

Concurrent And Distributed Systems

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An Architecture for Distributed Electronic Documents Storage in Decentralized Blockchain B2B Applications

Computers ◽

10.3390/computers10110142 ◽

2021 ◽

Vol 10 (11) ◽

pp. 142

Author(s):

Obadah Hammoud ◽

Ivan Tarkhanov ◽

Artyom Kosmarski

Keyword(s):

Distributed Systems ◽

Data Storage ◽

Distributed Storage ◽

Distributed Data ◽

Erasure Coding ◽

Distributed Data Storage ◽

Electronic Documents ◽

File Storage ◽

Load Balancer ◽

The Cost

This paper investigates the problem of distributed storage of electronic documents (both metadata and files) in decentralized blockchain-based b2b systems (DApps). The need to reduce the cost of implementing such systems and the insufficient elaboration of the issue of storing big data in DLT are considered. An approach for building such systems is proposed, which allows optimizing the size of the required storage (by using Erasure coding) and simultaneously providing secure data storage in geographically distributed systems of a company, or within a consortium of companies. The novelty of this solution is that we are the first who combine enterprise DLT with distributed file storage, in which the availability of files is controlled. The results of our experiment demonstrate that the speed of the described DApp is comparable to known b2c torrent projects, and subsequently justify the choice of Hyperledger Fabric and Ethereum Enterprise for its use. Obtained test results show that public blockchain networks are not suitable for creating such a b2b system. The proposed system solves the main challenges of distributed data storage by grouping data into clusters and managing them with a load balancer, while preventing data tempering using a blockchain network. The considered DApps storage methodology easily scales horizontally in terms of distributed file storage and can be deployed on cloud computing technologies, while minimizing the required storage space. We compare this approach with known methods of file storage in distributed systems, including central storage, torrents, IPFS, and Storj. The reliability of this approach is calculated and the result is compared to traditional solutions based on full backup.

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