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The Systems Engineering Methodology for Startups

Reading time6 min
Views1.8K

Creating a product startup can be an exciting experience, but it can be a daunting one as well. On average, only 1 out of 10 startups is successful, according to the Global Startup Ecosystem Report. Therefore, to raise your prospects, there are quite a number of important considerations to make in advance. 

Bearing in mind everything you need when launching a startup is a challenging task, so it’d be a sound idea to rely on some well-established methodology. That's why we were inspired by the Systems Engineering methodology, presented in such industry standards as ISO 15288 and CFR21. In this article, we’ll make a brief overview of this methodology and highlight how it can help entrepreneurs to encompass and structure the process of creating and developing a startup.

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Comments3

Metaverses: hype or the future to come?

Reading time5 min
Views1.5K

Alexander Volchek, IT entrepreneur, CEO educational platform GeekBrains

Pretty much everyone in the IT community is talking metaverses, NFTs, blockchain and cryptocurrency. This time we will discuss metaverses, and come back to everything else in the letters to follow. Entrepreneurs and founders of tech giants are passionate about this idea, and investors are allocating millions of dollars for projects dealing with metaverses. Let's start with the basics.

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Total votes 2: ↑1 and ↓10
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What are neural networks and what do we need them for?

Reading time4 min
Views4.1K

Explaining through simple examples

For a long time, people have been thinking on how to create a computer that could think like a person. The advent of artificial neural networks is a significant step in this direction. Our brain consists of neurons that receive information from sensory organs and process it: we recognize people we know by their faces, and we feel hungry when we see delicious food. All of this is the result of brain neurons working and interacting with each other. This is also the principle that artificial neural networks are based on, simulating the processes occurring in the human brain.

What are neural networks

Artificial neural networks are a software code that imitates the work of a brain and is capable of self-learning. Like a biological network, an artificial network also consists of neurons, but they have a simpler structure.

If you connect neurons into a sufficiently large network with controlled interaction, they will be able to perform quite complex tasks. For example, determining what is shown in a picture, or independently creating a photorealistic image based on a text description.

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Total votes 1: ↑1 and ↓0+1
Comments1

IDS Bypass at Positive Hack Days 11: writeup and solutions

Reading time10 min
Views1.8K

The IDS Bypass contest was held at the Positive Hack Days conference for the third time (for retrospective, here's . This year we created six game hosts, each with a flag. To get the flag, participants had either to exploit a vulnerability on the server or to fulfill another condition, for example, to enumerate lists of domain users.

The tasks and vulnerabilities themselves were quite straightforward. The difficulty laid in bypassing the IDS: the system inspected network traffic from participants using special rules that look for attacks. If such a rule was triggered, the participant's network request was blocked, and the bot sent them the text of the triggered rule in Telegram.

And yes, this year we tried to move away from the usual CTFd and IDS logs towards a more convenient Telegram bot. All that was needed to take part was to message the bot and pick a username. The bot then sent an OVPN file to connect to the game network, after which all interaction (viewing tasks and the game dashboard, delivering flags) took place solely through the bot. This approach paid off 100%!

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Total votes 3: ↑3 and ↓0+3
Comments0

An Antidote to Absent-Mindedness, or How I Gained Access to an OpenShift Node without an SSH Key

Reading time6 min
Views5.3K

Typically when a Node falls out of the OpenShift cluster, this is resolved by simply restarting the offending element. What should you do, however, if you’ve forgotten the SSH key or left it in the office? You can attempt to restore access by using your wit and knowledge of Linux commands. Renat Garaev, lead developer at Innotech, described how he found the solution for this riddle and what was the outcome.

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Wi-Fi and CWMP (TR-069) / USP (TR-369) protocols: frequency optimization attempt

Reading time14 min
Views5.8K

I guess, it's not a big deal to say that Wi-Fi (IEEE 802.11 standards) is the one of the most popular and most spread communication technology of the current day. Especially indoors. The growing number of Wi-Fi devices still remains that leads to the overcrowded spectrums: both 2.4 GHz and 5 GHz.


This fact means increasing of demand for some optimization routines for utilization of resources. And therefore some RRM (Radio Resource Management) systems become required.



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Total votes 1: ↑1 and ↓0+1
Comments0

Utilitarian blockchain. 1. Assets

Reading time8 min
Views1.4K
image

In the modern world, the term " **blockchain** " is steadily associated with cryptocurrencies, NFTs, mining, trading and financial pyramids. However, even among programmers and IT people there is not always a clear understanding of what it is and what it is for.

This article attempts to look at this still relatively new element of the information and human space in practical and slightly philosophical aspects.

> **Disclaimer**: The article will use simple language to explain non-trivial concepts, so non-critical distortion of technical details is possible.
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Information is changed by entropy

Reading time2 min
Views1.1K

According to the no-cloning theorem it is impossible to create an independent and identical copy of an arbitrary unknown quantum state. We cannot delete any quantum information as well. All changes in time of the state vector in quantum mechanics are described by the action of unitary operators. Accordingly, there must be an operator performing a deleting operation. The operator must be a zero matrix in order to nullify quantum information totally in all cases. But a zero matrix is not a uninaty or hermitian matrix. Therefore there is no such unitary operator that can delete information.

   This might be proven in another way. Let us imagine the double-slit thought experiment where interference exists when we do not know about the system and interference does not when we know about the system. Assume we have a storage where the data is stored and the experiment is being conducted with knowing about the system. Suppose we destroy the storage. What does the screen in the experiment show us? Quantum mechanics tells us that there must not be interference. Should it appear after the data is destroyed? Since the wave function has collapsed it cannot be restored. If there is a chance to delete the information in the experiment, it means that the wave function must go back to the initial state and show us interference, which is a contradiction.

   Based on the foregoing, we will consider the quantum eraser experiment. In that experiment information is neither erased nor disappeared. It is being changed. That is the key point. We increase entropy. If there is a 50 per cent chance to get interference then the entropy = 1 (max value). The same with a spin. If we change spins of elementary particles, for example in the Stern–Gerlach experiment with different axes measurements, we do not delete the information about the states of particles, we increase the entropy. Changing does not equal deleting. 

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Total votes 3: ↑3 and ↓0+3
Comments1

PHDays 11: bootkit infection, sanitizers for the Linux kernel, the new face of OSINT, and phishing on official websites

Reading time3 min
Views1.5K

Positive Hack Days 11 will begin in a matter of weeks. This international forum on practical security will be held on May 18–19 in Moscow.

As per tradition, PHDays will have three big tracks dedicated to countering attacks (defensive), protection through attack (offensive), and the impact of cybersecurity on business. It is our pleasure to present the first talks.

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Total votes 1: ↑0 and ↓1-1
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The journey of scaling up a production Elasticsearch cluster

Reading time6 min
Views3.2K

In this article, I will tell you about a-few-years journey of scaling the Elasticsearch cluster in production environment, which is one of the vital elements of the iPrice technology stack. 
I will describe challenges we encountered and how we approached them.

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Total votes 1: ↑1 and ↓0+1
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Introducing into calamares bootloader

Reading time13 min
Views4.9K


Overview


Sometimes all of us need to make a graphical installer for one's own linux distro. It goes without saying that you are able to use a distro-specific installer like Anaconda for RedHat-based or DebianInstaller for debian-based. On the other hand Calamares is a graphical installer which is not aligned with only one package manager.


I want to share my experience how to make a universal install solution with GUI. I did not find any complete article about it, hence, I reinvented the wheel.

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Total votes 2: ↑2 and ↓0+2
Comments0

The Cryptocurrency Bandwagon

Reading time8 min
Views1.7K

The spread of cryptocurrencies contributed to the development of many solutions based on a distributed ledger technology (blockchain). Although the scope of these solutions varies, most of them have the same basic set of security services, i.e. confidentiality, authenticity, and integrity. These features are granted by the practical applications of public key cryptography, in particular,  digital signature (DS). But unlike many other applications of public key cryptography, cryptocurrency networks do not use public key certificates. This is the aspect that we would like to talk about.

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Introduction to Engineering

Reading time16 min
Views1.9K

This is a set of chapters for young engineers. We give practical advice and discuss goals, challenges and approaches used in modern software engineering.

Along with classical foundations this article contains original ideas of conceptualizing engineer's work with emphasis on bringing order to the situation and finding an insight. Engineering is approached as work in uncertainty with other people which requires special skills. Non-obvious complications regarding modern production in big companies are discussed.

This article is based on 15 years of experience in engineering and management in high-tech industries.

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Comments3

Q4 2021 DDoS attacks and BGP incidents

Reading time6 min
Views1K

2021 was an action-packed year for Qrator Labs.

It started with the official celebration of our tenth year anniversary, continued with massive routing incidents, and ended with the infamous Meris botnet we reported back in September.

Now it is time to look at the events of the last quarter of 2021. There are interesting details in the BGP section, like the new records in route leaks and hijacking ASes, but first things first, as we start with the DDoS attacks statistics.

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Total votes 13: ↑13 and ↓0+13
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