Binary code: Mystery number one. Artur Zadikyan

citizens and services both at home and abroad. The rest, as the NSA believes, I will tell you in confidence, you don't have to ask.

      Ruthra smiled a little at the last sentence, giving his statement a joking tone that was meant to be taken as truth. The room chuckled approvingly, and Ruthra wondered if he had said more than he should have, for he now knew for certain that in the Echelon 2 system it functioned as a single system. He decided to define his position:

      – It seems unbelievable, but NSA spies can use analytical data for their own or third parties' benefit, as they listen and view everything. Edward Snowden, a National Security Agency official, orchestrated the leak of classified documents detailing how the U.S. government uses information technology to spy on potential terrorists. The Secret Service collects millions of phone calls, emails, photos and videos from Google, Facebook, Microsoft and other communications giants. But what do agencies like the NSA then do with that information?

      Rutra thought for a moment about how to present his position on the case, for he now knew that Echelon 2 had orchestrated the Snowden story so that Echelon 1 would realize that it would not be possible to use the information to their advantage, that there were structures beyond their control. So they were still puzzling over how that had happened. After a moment's thought, Ruthra continued:

      – Data flows around the world and the rapid growth of digital information are attracting the attention of both the private sector and public services. Processing these streams is becoming a promising endeavor. How much data do you and I produce? According to recent research by IBM, humanity generates 2.5 quintillion bytes of information every day. If these bytes were visualized as flattened pennies, they would cover the entire globe in five layers. Data collection by security services relies on the basic thesis that the entire mass of data can be analyzed in such a way that it can be used to identify connections between different people. By analyzing these connections, leads can be found for investigative purposes. The main principle in data processing is to supply each fragment with a label. Based on this metadata, computer algorithms will be able to identify connections of interest to the security service. Metadata is data that describes other data. This is, for example, the names and sizes of files on your computer. In the digital world, a label affixed to a piece of data would be called a tag. Providing data with a label is a mandatory first step in data processing, because it is the label that allows the analyst or his program to classify and organize the available information for further processing and analysis. Tags allow you to manipulate data fragments without having to go into their content. This is a very important legal point in the work of the Security Service, because the US law does not allow to open the correspondence of US citizens, as well as foreigners staying in the country legally, without an appropriate warrant. Therefore, the NSA uses a special, highly sophisticated program that "tags" all collected information. These are the basis for any system that links different types of data: video files, documents, phone records. For example, a data processing system can draw the attention of investigators to a suspect who posts terrorist propaganda online, visits websites that describe the technology of making improvised explosive devices, and buys, for example, a pressure cooker. One such program is called Accumulo. It is used for surveillance in international communication systems, and it was created precisely to tag billions of disparate data fragments. It's the security service's "secret weapon." The NSA has the right to perlustrate international communication channels and collects huge amounts of data. These are trillions of fragments of various messages that people write all over the world. The agency does not hunt for criminals, terrorists or spies that are identified through its work, but simply leaks the information obtained to other government services – the Pentagon, the FBI and the CIA. The work then proceeds according to this scheme. First, one of the 11 judges of the secret FISA court accepts a request from a government agency for permission to reprocess certain data obtained by the NSA. Upon receiving authorization, the request is first forwarded to the FBI's Electronic Communications Surveillance Unit – ECSU. This move is to ensure legal correctness – FBI agents verify the request and confirm that the targets of the surveillance are not U.S. citizens. ECSU forwards the same request to the FBI's Data Interception Techniques Unit. They receive the information from the Internet servers and pass it on to the NSA to run it through their data processing programs. Many communications companies deny that their servers are open to NSA access. Federal officials, on the other hand, report evidence of such cooperation. Finally, the NSA passes the relevant information to the government agency from which the request was made.

      Ruthra noticed how attentively his audience was listening. Clearly they had not expected this. Of course, the audience included employees and officials with high security clearances.

      – No sooner had the public digested the information about metadata than Snowden bombarded them with a story about another area of the NSA's work, labeled US-984XN. Every search platform, every source of raw intelligence information gets its own designation and code name. The SIGAD US-984XN service is known by the oft-mentioned code name PRISM. The PRISM system is the collection of digital photographs, files stored somewhere and sent somewhere, emails, chats, videos, and video conversations. This information is being seized from nine leading internet companies. The schemes made public by Snowden show that the NSA, among other things, uses real-time surveillance tools in its operations. The agency's analysts can receive alerts when a user connects to a service or sends an email, or logs into a particular chat room. Snowden published a top-secret report that described software that could look at hundreds of different databases. It is now no longer a secret that these programs allow the lowest level analyst to interfere unchecked with other people's information sharing processes. The report gives examples such as, "My client speaks German but is in Pakistan. How do I find him?" or "My client uses Google Maps to find his targets. Can I use this information to determine his email address?" The described program allows, having asked one such question, to simultaneously search through 700 servers scattered all over the world.

      Ruthra was silent for a moment and then continued. He described the various schemes of the tracking systems and gave examples.

      – Among other things, the NSA itself is asking other agencies to help. So-called information-sharing cooperation. The essence is that, for example, the German intelligence agency BND, commissioned by the NSA, conducts surveillance of targets throughout Europe. Intelligence activities are carried out in accordance with a list of tens of thousands of criteria for information retrieval. These include IP addresses, phone numbers, social media accounts, and email domains.

      Ruthra fell silent, then looked at the lecturer who had invited him and said:

      – I'm done. Thank you for your attention.

      The audience clapped approvingly. The audience tried to get through to Rutre, who was being hurried away by Zhidkov. They were followed by the lecturer, who, in English, suggested that Rutra give periodic lectures as part of the existing arrangements for the exchange of experience. Vasilievich nodded approvingly, arching his eyebrows. The latter nodded back. Rutra did not quite understand the meaning of this gesture, but he noticed that he had made an impression on everyone.

      After passing through the guarded secret library, in front of which Zero's security zone was thoughtfully located (the guards wore FSO uniforms), they silently began to descend by elevator. Both of them were thinking, pondering.

      The first to break the silence was the chief:

      – Now, after all this information flows into our center that no one can know about. Center Zero. Why is it located in Russia? Because it is easier to create a center closed from the public in Russia than in any other civilized country.

      ***

      A general meeting was scheduled for Monday morning. Yuri Vasilievich gave the speech.

      – The reason I've gathered you here is the Perimeter system, or rather, a malfunction that was miraculously eliminated. It's lucky that we identified it at all, although, frankly speaking, there have been rumors about the system's "waywardness" for a long time. All right, esteemed employees. This is a very important part of our work, but it should not be to the detriment of other duties. That's the first thing. Second: Rutre Tigrovic is in charge of the investigation. He will do the main work. You'll gather material for him. Third: I'll introduce you to the system in general terms, the rest you'll learn on your own.

      Everyone