Distributed systems

VeChain Has Introduced Blockchain-Based Healthcare Data Management Platform At Cyprus Hospital

• Distributed systems,
• Software,
• Artificial Intelligence

Blockchain possesses incredible potential, that's why blockchain systems are considered as a paradise for data. In all these years, the discovery of Blockchain has been enjoyed for the introduction of distributed systems to secure data by cryptography.

From the creation of cryptocurrency to distributed ledger systems and mobile applications, this technology is being welcomed by every business vertical, and its adoption has become complimentary for companies. Moreover, its adoption can majorly be cherished by the healthcare industry.

A number of IT institutions are engaged in finding the most promising usage of blockchain technology in healthcare. Let's take a brief look at Blockchain adoption in 2020.

The Global Blockchain Adoption

In 2020, the worldwide spending on blockchain systems is USD 4.3 billion. As per Statista, the market of Blockchain will be worth 20 billion USD by the year 2025. Its most critical adoption can be seen in the healthcare industry, where this technology is being considered as the biggest game-changer.



The truth is that this technology has shown a path to distributed systems coupled with unmatched security measures That secure data in a chain of blocks infused with cryptographic locks. Top-notch level security and quality of not being tempered by any external entity boost its adoption in several instances.

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dokshina April 13, 2020 at 02:34 PM

Deploying Tarantool Cartridge applications with zero effort (Part 2)

• Mail.ru Group corporate blog,
• High performance,
• IT Infrastructure,
• Database Administration,
• Distributed systems

• Tutorial

We have recently talked about how to deploy a Tarantool Cartridge application. However, an application's life doesn't end with deployment, so today we will update our application and figure out how to manage topology, sharding, and authorization, and change the role configuration.

Feeling interested? Please continue reading under the cut.

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rwaltzsoftware January 27, 2020 at 04:34 PM

Blockchain Is Changing The Way Rail Industry Works

• Distributed systems,
• IT-companies

• From sandbox

Railways had made our transportation very easy since 1830 when the first railway began in England. From 1830 to 2020, the development in the railways has been quite significant. The concept of blockchain is expanding widely; hence the public interests are also growing on a vast scale. Major enthusiasts about blockchain are the investors and businessmen who wish for transparency and equity in the transaction. Now since blockchain is no more just a concept its application in railways is expected to smoothen the transportation.

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dokshina December 16, 2019 at 12:41 PM

Deploying Tarantool Cartridge applications with zero effort (Part 1)

• Mail.ru Group corporate blog,
• High performance,
• IT Infrastructure,
• Database Administration,
• Distributed systems

We have already presented Tarantool Cartridge that allows you to develop and pack distributed applications. Now let's learn how to deploy and control these applications. No panic, it's all under control! We have brought together all the best practices of working with Tarantool Cartridge and wrote an Ansible role, which will deploy the package to servers, start and join instances into replica sets, configure authorization, bootstrap vshard, enable automatic failover and patch cluster configuration.

Interesting, huh? Dive in, check details under the cut.

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Ontologic October 17, 2019 at 09:44 AM

How to Write a Smart Contract with Python on Ontology? Part 4: Native API

• Cryptography,
• Python,
• DevOps,
• Distributed systems,
• Cryptocurrencies

• Tutorial

Earlier, I have introduced the Ontology Smart Contract in
Part 1: Blockchain & Block API and
Part 2: Storage API
Part 3: Runtime API
Today, let’s talk about how to invoke an Ontology native smart contract through the Native API. One of the most typical functions of invoking native contract is asset transfer.

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Tarantool Data Grid: Architecture and Features

• Mail.ru Group corporate blog,
• High performance,
• Lua,
• Data storage,
• Distributed systems

In 2017, we won the competition for the development of the transaction core for Alfa-Bank's investment business and started working at once. (Vladimir Drynkin, Development Team Lead for Alfa-Bank's Investment Business Transaction Core, spoke about the investment business core at HighLoad++ 2018.) This system was supposed to aggregate transaction data in different formats from various sources, unify the data, save it, and provide access to it.

In the process of development, the system evolved and extended its functions. At some point, we realized that we created something much more than just application software designed for a well-defined scope of tasks: we created a system for building distributed applications with persistent storage. Our experience served as a basis for the new product, Tarantool Data Grid (TDG).

I want to talk about TDG architecture and the solutions that we worked out during the development. I will introduce the basic functions and show how our product could become the basis for building turnkey solutions.

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Rosik October 9, 2019 at 05:32 PM

Тarantool Cartridge: Sharding Lua Backend in Three Lines

• Mail.ru Group corporate blog,
• High performance,
• Server optimization,
• Lua,
• Distributed systems

In Mail.ru Group, we have Tarantool, a Lua-based application server and a database united. It's fast and classy, but the resources of a single server are always limited. Vertical scaling is also not the panacea. That is why Tarantool has some tools for horizontal scaling, or the vshard module [1]. It allows you to spread data across multiple servers, but you'll have to tinker with it for a while to configure it and bolt on the business logic.

Good news: we got our share of bumps (for example, [2], [3]) and created another framework, which significantly simplifies the solution to this problem.

Тarantool Cartridge is the new framework for developing complex distributed systems. It allows you to concentrate on writing business logic instead of solving infrastructure problems. Under the cut, I will tell you how this framework works and how it could help in writing distributed services.

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Ontologic October 9, 2019 at 06:40 AM

How to Write a Smart Contract with Python on Ontology? Part 2: Storage API

• Python,
• Programming,
• DevOps,
• Distributed systems,
• Cryptocurrencies

• Tutorial

This is an official tutorial published earlier on Ontology Medium blog
Excited to publish it for Habr readers. Feel free to ask any related questions and suggest a better format for tutorial materials

Foreword

Earlier, in Part 1, we introduced the Blockchain & Block API of Ontology’s smart contract. Today we will discuss how to use the second module: Storage API. The Storage API has five related APIs that enable addition, deletion, and changes to persistent storage in blockchain smart contracts. Here’s a brief description of the five APIs:

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Ontologic September 25, 2019 at 01:55 PM

How to Write a Smart Contract with Python on Ontology? Part 1: the Blockchain & Block API

• Python,
• Distributed systems,
• Cryptocurrencies

• From sandbox

This is an official tutorial published earlier on Ontology Medium blog
Excited to publish it for Habr readers. Feel free to ask any related questions and suggest a better format for tutorial materials

Foreword

In this article, we will begin to introduce the smart contract API of Ontology. The Ontology’s smart contract API is divided into 7 modules:

• Part 1: Blockchain & Block API
• Part 2: Storage API
• Part 3: Runtime API
• Part 4: Native API
• Part 5: Upgrade API
• Part 6: Execution Engine API
• Part 7: Static & Dynamic Call API

In this article, we will introduce the Blockchain & Block API, which is the most basic part of the Ontology smart contract system. The Blockchain API supports basic blockchain query operations, such as obtaining the current block height, whereas the Block API supports basic block query operations, such as querying the number of transactions for a given block.

Let’s get started!

First, create a new contract in SmartX and then follow the instructions below.

1. How to Use Blockchain API

References to smart contract functions are identical to Python’s references. Developers can introduce the appropriate functions as needed. For example, the following statement introduces GetHeight, the function to get the current block height, and GetHeader, the function to get the block header.

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Shapelez August 15, 2019 at 12:22 AM

Qrator filtering network configuration delivery system

• Qrator Labs corporate blog,
• System Analysis and Design,
• IT Infrastructure,
• Network technologies,
• Distributed systems

TL;DR: Client-server architecture of our internal configuration management tool, QControl.
At its basement, there’s a two-layered transport protocol working with gzip-compressed messages without decompression between endpoints. Distributed routers and endpoints receive the configuration updates, and the protocol itself makes it possible to install intermediary localized relays. It is based on a differential backup (“recent-stable,” explained further) design and employs JMESpath query language and Jinja templating for configuration rendering.

Qrator Labs operates on and maintains a globally distributed mitigation network. Our network is anycast, based on announcing our subnets via BGP. Being a BGP anycast network physically located in several regions across the Earth makes it possible for us to process and filter illegitimate traffic closer to the Internet backbone — Tier-1 operators.

On the other hand, being a geographically distributed network bears its difficulties. Communication between the network points-of-presence (PoP) is essential for a security provider to have a coherent configuration for all network nodes and update it in a timely and cohesive manner. So to provide the best possible service for customers, we had to find a way to synchronize the configuration data between different continents reliably.

In the beginning, there was the Word… which quickly became communication protocol in need of an upgrade.

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olegchir June 28, 2019 at 01:55 PM

The big interview with Martin Kleppmann: “Figuring out the future of distributed data systems”

• JUG Ru Group corporate blog,
• Programming,
• Conferences,
• Distributed systems,
• Interview

Dr. Martin Kleppmann is a researcher in distributed systems at the University of Cambridge, and the author of the highly acclaimed «Designing Data-Intensive Applications» (O'Reilly Media, 2017). 

Kevin Scott, CTO at Microsoft once said: «This book should be required reading for software engineers. Designing Data-Intensive Applications is a rare resource that connects theory and practice to help developers make smart decisions as they design and implement data infrastructure and systems.»

Martin’s main research interests include collaboration software, CRDTs, and formal verification of distributed algorithms. Previously he was a software engineer and an entrepreneur at several Internet companies including LinkedIn and Rapportive, where he worked on large-scale data infrastructure.

Vadim Tsesko (@incubos) is a lead software engineer at Odnoklassniki who works in Core Platform team. Vadim’s scientific and engineering interests include distributed systems, data warehouses and verification of software systems.

Contents:

• Moving from business to academic research;
  
• Discussion of «Designing Data-Intensive Applications»;
  
• Common sense against artificial hype and aggressive marketing;
  
• Pitfalls of CAP theorem and other industry mistakes;
  
• Benefits of decentralization;
  
• Blockchains, Dat, IPFS, Filecoin, WebRTC;
  
• New CRDTs. Formal verification with Isabelle;
  
• Event sourcing. Low level approach. XA transactions; 
  
• Apache Kafka, PostgreSQL, Memcached, Redis, Elasticsearch;
  
• How to apply all that tools to real life;
  
• Expected target audience of Martin’s talks and the Hydra conference.
  

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Flightradar24 — how does it work? Part 2, ADS-B protocol

• Python,
• IT Standards,
• Distributed systems,
• Popular science,
• Systems engineering

I’m going to have a guess and say that everyone whose friends or family have ever flown on a plane, have used Flightradar24 — a free and convenient service for tracking flights in real time.



In the first part the basic ideas of operation were described. Now let's go further and figure out, what data is exactly transmitting and receiving between the aircraft and a ground station. We'll also decode this data using Python.

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BitfuryRussia March 10, 2019 at 07:01 PM

Crystal Blockchain Analytics: Investigating the Hacks and Theft Cases

• Bitfury Group corporate blog,
• Information Security,
• System Analysis and Design,
• Distributed systems,
• Cryptocurrencies

In this report, Bitfury shares analysis completed by its Crystal Blockchain Analytics engineering team on the movement of bitcoin from the Zaif exchange, Bithumb exchange and Electrum wallets.

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BitfuryRussia February 14, 2019 at 11:35 AM

Building a Private Currency Service Using Exonum

• Bitfury Group corporate blog,
• Development for e-commerce,
• Distributed systems,
• Finance in IT

Zero-knowledge proofs/arguments are an emerging cryptographic technology that promises to bring us closer to the Holy Grail of blockchain: providing data privacy and auditability.

Potential applications for zero-knowledge include, but are not limited to:

• Inter-bank transfer systems (see a research paper by Narula et al.)
• Privacy-focused management of digital assets (see a proof of concept by J.P. Morgan and zCash)
• KYC (see a proof of concept by ING)
• Self-sovereign identity (see an attribute-based credentials EU project)
• Voting (see a proxy voting prototype by Russian National Security Depository)

Another application for zero-knowledge proofs is helping blockchains scale. ZKPs allow for the “compressing” of computations for blockchain transactions without sacrificing security.

In this article, we describe how zero-knowledge (specifically, Bulletproofs) can be applied to build a privacy-focused service using Bitfury’s Exonum platform.

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BitfuryRussia February 6, 2019 at 09:00 PM

Generic Methods in Rust: How Exonum Shifted from Iron to Actix-web

• Bitfury Group corporate blog,
• Programming,
• System Analysis and Design,
• Rust,
• Distributed systems

The Rust ecosystem is still growing. As a result, new libraries with improved functionality are frequently released into the developer community, while older libraries become obsolete. When we initially designed Exonum, we used the Iron web-framework. In this article, we describe how we ported the Exonum framework to actix-web using generic programming.

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The authoritative guide to Blockchain Sharding

• High performance,
• Distributed systems,
• Cryptocurrencies

datacompboy January 15, 2019 at 04:15 PM

What to think during NALSD interview

• Google Developers corporate blog,
• High performance,
• System Analysis and Design,
• IT career,
• Distributed systems

There are a lot of posts about what a typical coding interview at Google looks like. But, while not as widely described and discussed, there is also quite often a system design interview. For an SRE position it’s NALSD: non-abstract large system design. The key difference between SWE and SRE interviews consists in these two letters: NA.

So, what is the difference? How to be prepared for this interview? Let’s be non-abstract, and use an example. To be more non-abstract, let’s take something from the material world, such that you won’t be asked the exact same thing at the real interview (at least, not at the Google interview) :)

So, let’s design a public library system. For the paper books, like you have seen everywhere around. The whole text below was written all at once within around one hour, to roughly show you the areas that you should be able to cover / touch during the interview. Please excuse some disorder, that’s how I think (therefore I am).

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