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I created a new console for Microsoft System Center Orchestrator. It doesn't require Silverlight.

The third quarter of 2021 brought a massive upheaval in the scale and intensity of DDoS attacks worldwide.

It all led to September when together with Yandex, we uncovered one of the most devastating botnets since the Mirai and named it Meris, as it was held accountable for a series of attacks with a very high RPS rate. And as those attacks were aimed all over the world, our quarterly statistics also changed.

This quarter, we've also prepared for your consideration a slice of statistics on the application layer (L7) DDoS attacks. Without further ado, let us elaborate on the details of DDoS attacks statistics and BGP incidents for Q3, 2021.

I am not an economist, but in light of current events with cryptocurrencies and the economy in general, I would like to share my thoughts on some kind of ideal economy, around which everything is happening now.

I had some experience in the matching engine development for cryptocurrency exchange some time ago. That was an interesting and challenging experience. I developed it in clear C++ from scratch. The testing of it is also quite a challenging task. You need to get data for testing, perform testing, collect some statistics, and at last, analyze collected data to find weak points and bottlenecks. I want to focus on testing the C++ matching engine and show how testing can give insights for optimizations even without the need to change the code. The matching engine I developed can do more than 1’000’000 TPS (transactions per second) and is 10x times faster than the matching engine of the Binance cryptocurrency exchange (see one post on Binance Blog).

Recently we released a new build of the Big Data Tools plugin that is compatible with the 2021.3 versions of IntelliJ IDEA and PyCharm. DataGrip 2021.3 support will be available immediately after the release in October. The plugin also supports our new data science IDE – JetBrains DataSpell. If you still use previous versions, now is the perfect time to upgrade both your IDE and the plugin. 

This year, we introduced a number of new features as well as some features that have been there for a while, for example, running Spark Submit with a run configuration.

Here’s a list of the key improvements:

Introduction

For the last five years, there have virtually been almost no global-scale application-layer attacks.

During this period, the industry has learned how to cope with the high bandwidth network layer attacks, including amplification-based ones. It does not mean that botnets are now harmless.

End of June 2021, Qrator Labs started to see signs of a new assaulting force on the Internet – a botnet of a new kind. That is a joint research we conducted together with Yandex to elaborate on the specifics of the DDoS attacks enabler emerging in almost real-time.

This article continues the series of articles on load tests. Today we will analyze the testing methodology and answer the question: "How many IP cameras can be connected to a WebRTC server?"

• We’ll find out what is an in-memory database, or IMDB. When and how are they better than disk solutions?
• Then, we’ll consider their architecture. What about their efficiency, reliability, and scaling?
• Then, we’ll delve into technical details. Data types, iterators, indexes, transactions, programming languages, replication, and connectors.

Do you remember how just a few years ago it was a disaster to lose a camera at the end of a vacation? All memorable pictures and videos then disappeared along with the lost device. Probably, this fact prompted the great minds to invent cloud storage, so that the safety of records no longer depends on the presence of the devices on which these records are made.

We continue to review variants of load tests. In this article we will go over the testing methodology and conduct a load test that we will use to try and determine the number of users that could watch and stream at the same time, meaning the users will simultaneously publish and view the streams.

This article is a continuation of our series of write-ups about load tests for our server. We have already discussed how to compile metrics and how to use them to choose the equipment, and we also provided an overview of various load testing methods. Today we shall look at how the server handles stream mixing.

In this video, we will look at how to connect brushless motor controllers to a Linux computer. Specifically, we will use a computer running Debian. The same steps would work for Ubuntu Linux and other Linux distributions derived from Debian.

I've got a small sensorless brushless motor, and a bigger brushless motor with a built-in absolute encoder. Lets look at how to control those from my Debian Linux computer. Servosila brushless motor controllers come in several form factors with either a circular or a rectangular shape. The controllers come with a set of connectors for motors and encoders as well as for USB or CANbus networks.

The controllers can be powered by a power supply unit or by a battery. To spice up my setup, I am going to use a battery to power the controllers and thus their motors. The controllers need 7 to 60 volts DC of voltage input. If I connect the battery, the controllers get powered up. The small LED lights tells us that the controllers are happy with the power supply.

We need to connect the brushless motor controllers to the Linux computer. There are two ways to do that - via CANbus or via USB. Lets look at the USB option first. A regular USB cable is used. Only one of the controllers needs to be connected to a computer or a PLC.

Next, we need to build an internal CANbus network between the controllers. We are going to use a CANbus cross-cable to interconnect the controllers. Each controller comes with two identical CANbus ports that help chain multiple controllers together in a network. If one of the interconnected brushless motor controllers is connected to a computer via USB, then that particular controller becomes a USB-to-CANbus gateway for the rest of the network. Up to 16 controllers can be connected this way via a single USB cable to the same control computer or a PLC. The limit is due to finite throughput of the USB interface.

In the previous article we went over a load test whose data could be used to choose a load-appropriate server. In the course of the testing, we would publish a stream on one WCS, and we would pick up that stream several times using a second WCS. The acquired results could be used as a basis for decisions on server operability.

Some would (justly) have concerns regarding the possible biases in such a test — after all, one of our servers was used to test another one of our servers. Could it be that we were using a specially optimized code that skewed the results in our favor?

ENCRY presents a new interactive identification protocol aimed at controlling the access of selected users to various resources.

Close your eyes and imagine Nice, a luxurious estate whose extravagant owner throws epic parties with jazz and fireworks every weekend.

To attend such a party is a lot of the elite. Invitations are sent out in advance, and guests do not know the names of other invited persons. The owner of the estate, the mysterious Jay Gatsby, an eager luxury-lover, values ​​privacy so much that he is not ready to entrust the list of invitees to anyone, not even his buttress. Moreover, the owner of the estate would like the guests not to reveal their names when entering the property. After all, there may be the mayor of the city, or the chief prosecutor among them, and they would like to keep their visit secret. Unfortunately, the owner of the estate himself is so busy that he cannot independently check each guest at the entrance, especially since there are several access roads to his house. How could he solve this problem?

If you use Zabbix to monitor your infrastructure objects but have not previously thought about collecting and storing logs from these objects then this article is for you.

In any project, a great deal of importance is placed on the selection of server hardware and WebRTC streaming is no exception. One of the key principles of such a selection is balance – the hardware should be powerful enough to handle the streams with no drops in quality, but not too powerful so as to waste resources. So, how does one choose the right server?

Monitoring systems are a vital tool for any system administrator, because they can be used to extract specific information from services, such that:

In the first part of You don't know Redis, I built an app using Redis as a primary database. For most people, it might sound unusual simply because the key-value data structure seems suboptimal for handling complex data models.

In practice, the choice of a database often depends on the application’s data-access patterns as well as the current and possible future requirements.

Redis was a perfect database for a Q&A board. I described how I took advantage of sorted sets and hashes data types to build features efficiently with less code.

Now I need to extend the Q&A board with registration/login functionality.

I will use Redis again. There are two reasons for that.

Firstly, I want to avoid the extra complexity that comes with adding yet another database.

Secondly, based on the requirements that I have, Redis is suitable for the task.

Important to note, that user registration and login is not always about only email and password handling. Users may have a lot of relations with other data which can grow complex over time.

Despite Redis being suitable for my task, it may not be a good choice for other projects.

Always define what data structure you need now and may need in the future to pick the right database.

RAM disk, this is a disk based on RAM memory chips. This kind of disk is not able to retain data after the power is turned off (unless a supporting battery is used), but has an exceptionally high read/write speed (especially for random access) and an unlimited lifespan. It is important in tasks that need a lot of cycles to write over information, even professional SSD drives don’t live long. To the operating system the RAM disk is indistinguishable from an SSD or HDD disk and no special drivers or setup is required. Unlike a disk that is virtually located in the computer’s RAM memory, where the maximum memory capacity is limited to 128-256 GB in the best consumer motherboards, a RAM disk for a PCIe slot, in general, has no volume limits and can work in any MB with a PCIe slot.