PVS-Studio has a mascot that became inseparable from the brand - a unicorn. Lately we've been getting many questions about our magic steed: why the unicorn, why has he changed so much, does he have hooves, how come he doesn't wear pants, and how do we draw him. The answers are finally here, in this very article.
Attention: there will be a lot of pictures. And I mean A LOT.
On implementing streaming algorithms, counting of events often occurs, where an event means something like a packet arrival or a connection establishment. Since the number of events is large, the available memory can become a bottleneck: an ordinary 
-bit counter allows to take into account no more than 
events.
One way to handle a larger range of values using the same amount of memory would be approximate counting. This article provides an overview of the well-known Morris algorithm and some generalizations of it.
Another way to reduce the number of bits required for counting mass events is to use decay. We discuss such an approach here [3], and we are going to publish another blog post on this particular topic shortly.
In the beginning of this article, we analyse one straightforward probabilistic calculation algorithm and highlight its shortcomings (Section 2). Then (Section 3), we describe the algorithm proposed by Robert Morris in 1978 and indicate its most essential properties and advantages. For most non-trivial formulas and statements, the text contains our proofs, the demanding reader can find them in the inserts. In the following three sections, we outline valuable extensions of the classic algorithm: you can learn what Morris's counters and exponential decay have in common, how to improve the accuracy by sacrificing the maximum value, and how to handle weighted events efficiently.
The year 2021 started on such a high note for Qrator Labs: on January 19, our company celebrated its 10th anniversary. Shortly after, in February, our network mitigated quite an impressive 750 Gbps DDoS attack based on old and well known DNS amplification. Furthermore, there is a constant flow of BGP incidents; some are becoming global routing anomalies. We started reporting in our newly made Twitter account for Qrator.Radar.
Nevertheless, with the first quarter of the year being over, we can take a closer look at DDoS attacks statistics and BGP incidents for January - March 2021.
__int128 add1(__int128 a, __int128 b) {
return b + a;
}
Why is it valuable to get into the Qrator Labs partnership program?
In Qrator Labs, we firmly believe that working together brings a better result. Which is the reason why, for years, we were trying to find meaningful partnerships with all kinds of companies. They either seek to provide their existing customers with the top-notch DDoS mitigation technology developed at Qrator Labs with many additional ecosystem solutions or want to succeed the other way around. By getting their product available for Qrator Labs' customers by integrating into the Qrator anycast filtering network.
Author: Chris Punches (@cmpunches, Silo group). License: "Please feel free to share unmodified".
The following text is an unmodified copy of now removed issue #2250 on rms-open-letter.github.io repository. The text claims multiple violations of different policies, codes of conduct and other documents in creation, content and support of the "Open letter to remove Richard M. Stallman from all leadership positions". The issue has not been addressed.
By the beginning of 2021, Qrator Labs filtering network expands to 14 scrubbing centers and a total of 3 Tbps filtering bandwidth capacity, with the San Paolo scrubbing facility fully operational in early 2021;
New partner services fully integrated into Qrator Labs infrastructure and customer dashboard throughout 2020: SolidWall WAF and RuGeeks CDN;
Upgraded filtering logic allows Qrator Labs to serve even bigger infrastructures with full-scale cybersecurity protection and DDoS attacks mitigation;
The newest AMD processors are now widely used by Qrator Labs in packet processing.
DDoS attacks were on the rise during 2020, with the most relentless attacks described as short and overwhelmingly intensive.
However, BGP incidents were an area where it was evident that some change was and still is needed, as there was a significant amount of devastating hijacks and route leaks.
In 2020, we began providing our services in Singapore under a new partnership and opened a new scrubbing center in Dubai, where our fully functioning branch is staffed by the best professionals to serve local customers.
As Intel Threading Building Blocks (TBB) is being refreshed using new C++ standard, deprecating tbb::task interface, the need for high-level tasking interface becomes more obvious. In this article, I’m proposing yet another way of defining what a high-level parallel task programming model can look like in modern C++. I created it in 2014 and it was my last contribution to TBB project as its core developer after 9 wonderful years of working there. However, this proposal has not been used in production yet, so a new discussion might help it to be adopted.
I'm Ivan Kopenkov, a senior front-end developer at Mail.ru Cloud Solutions. In this article, I will tell you about the approaches we have used for the UI library components customization. You will also learn how to significantly decrease bundle size, cutting off all the unnecessary modules Ant Design takes there.
In our case, we are making wrappers for original Ant Design components inside the project, changing their appearance, and developing their logic. At the same time, we import both customized and original components right from the ant-design module. That saves tree shaking functionality and makes complex library components use our wrappers instead of original nested elements.
If you are already or about to use Ant Design, this article will provide you with a better and more effective way to do so. Even if you have chosen another UI library, you might be able to implement these ideas.
At the beginning of the year 2021, Qrator Labs is celebrating its 10 year anniversary. On January 19 our company marks the official passing of a formal 10 years longevity mark, entering its second decade of existence.
Everything started a little bit earlier - when at the age of 10 Alex saw the Robotron K 1820 - in 2008, when Alexander Lyamin - the founder and CEO of Qrator Labs, approached the Moscow State University superiors, where he worked as a NOC engineer at the time, with an idea of a DDoS-attack mitigation research project. The MSU's network was one of the largest in the country and, as we know now, it was the best place to hatch a future technology.
That time MSU administration agreed, and Mr Lyamin took his own hardware to the university, simultaneously gathering a team. In two years, by summer 2010, the project turned out to be that successful. It courted the DDoS attack of a bandwidth exceeding the MSU's upstream bandwidth capability. And on June 22 MSU superiors gave Mr Lyamin a choice - to shut down or find money to incorporate.
Alexander Lyamin chose to incorporate with his own means, which effectively meant that the needed infrastructure must be built from scratch. The initial design should be distributed instead of concentrated within one network, which resources were not enough for this specific task. And by September 1, 2010, those first server sites were ready and running.
When we think about robots, the first thing that comes to mind are robotic vacuum cleaners. The reason is simple: they are the most "solid" demonstration of success of "consumer" robotics. So making one sounds like a good idea... at first.
But isn't it a bit counter productive - to build something that popular, something we can buy in a store at a commodity (small) price? Should we build something similar, but NOT a vacuum cleaner? Something like... a floor washer, perhaps? Yes, a robotic floor washer.
In this tutorial I am going to build a fully working prototype of a robotic floor washer. By "fully working" I mean that it is going to wash floor, instead of moving dirt around like most robotic "moppers" do. While by "prototype" I mean it is going to be the first step towards production-ready unit, but not a production-ready unit yet. Let me explain.
First of all, it is not going to be THAT solid. You can grab a robotic vacuum cleaner that you got from the store by any part, including wheels and bumper and lift it. It will not fall apart. Ours probably will. The reason is, to make a device "mechanically solid" is a separate task, and if we focus on it, then "robotic" tasks will become more difficult to achieve. So we are going to do what engineers usually do: first they build C3PO without the outside body, wires everywhere and so on. And only then they put a gold-covered outfit on it.
This is a transcription of a talk that was presented at CSNOG 2020 — video is at the end of the page
rotor is a non-intrusive event loop friendly C++ actor micro framework, similar to its elder brothers like caf and sobjectizer. The new release came out under the flag of pluginization, which affects the entire lifetime of an actor.