Means of protecting speech information. Protection of information from leakage through acoustic channels Basic methods and means of protecting acoustic information

Anyone who has something to keep secret from others, when using a telephone, sooner or later thinks about how to protect themselves from wiretapping. The problem arises of choosing a means of protection from the abundance available on Russian market. This task is of particular importance with the development of IP telephony technology.

When using a telephone, we, wittingly or unwittingly, trust it with information that is sometimes confidential. This may be information relating to personal life or personal data of employees of organizations. Information containing commercial or banking secrets may be transmitted over the phone. Generally speaking, when two people communicate on the phone, it is assumed that no one else can hear them, and the communication line is protected from eavesdropping by third parties.Unfortunately this is far from the case. In PSTN, electrical signals propagate in the clear over communication lines.

Almost any attacker, having the appropriate equipment, can gain access to confidential information transmitted to the PSTN using:

Direct connection to telephone lines;

Contactless collection of information and “bugs”;

Radiation in the radio and optical frequency spectra.

So how can you protect speech information? Currently, two areas of speech information protection are actively developing. One of them is related to the physical protection of telephone lines and the acoustic protection of conversations. Another direction of protecting telephone voice communications is based on information transformation of telephone signals and messages

MEANS OF PHYSICAL PROTECTION OF VOICE INFORMATION

Speech masking- an effective tool that provides a high degree of protection for telephone conversations. The masker is a noise generator whose correlation characteristics can change dynamically during negotiations. When transmitting voice information, the masker on the receiving side emits intense noise into the line in the frequency band of the telephone channel, which spreads along the entire communication line, creating strong interference for the attacker. At the same time, the noise signal of the masker is used to compensate for interference in the incoming “mixture” of speech signal and interference (using an adaptive filter). As a result, on the receiving side the subscriber hears speech without interference, but the attacker hears speech with interference. As a rule, the masker is connected on the side of the receiving subscriber (one-way masker), although it is also possible to connect on the side of the transmitting subscriber (two-way masker). In the latter case, the possibility of duplex mode of telephone conversations disappears, since each masker will need to be turned on and off one by one. An inconvenience when using maskers is the presence of strong noise on the transmitting side. One-way speech maskers are built into a number of devices, including: the Tu-man device, which has a barrier interference level of up to 1 W in the frequency band 0.5 - 3.5 kHz; Soundpress device with noise power 2 W; as well as the protective telephone module SI-2001.

Connection neutralizers to the telephone line ensure the creation of irreversible physical and chemical transformations in the technical means used by the attacker. The neutralizer emits a short-term signal (over 1.5 kV) or a series of short pulses into the line, which destroys the input circuits of the connected devices. Typically, devices for the physical destruction of devices for unauthorized recording of speech information burn out “bugs” at a distance of 200-300 m. Such neutralizers are Bugroaster (bugs burner), PTL-1500 (telephone line burner) and “Cobra” (embedded device burner). Passive protection means are frequency filters, blockers and other devices that, as a rule, are installed in a break in the telephone line or in the circuit of a telephone set to prevent the possibility of listening to conversations through the telephone line in the hang-up mode. Such devices, however, do not protect the telephone line from interception during a conversation. Means of passive protection of speech information: Korund-M device, MT202 blocking filter, MT201 telephone bug blocker, LST 1007A telephone line indicator. Active jamming means are used to protect the “telephone set - PBX” section. They provide the installation of barrage interference in the telephone line and some change in the standard parameters of the telephone channel (for example, the level of transmission/reception of the telephone signal). The interference exceeds the nominal level of the telephone signal by one or two or more orders of magnitude and, affecting the input stages and power devices of the means for intercepting voice information in the communication channel, takes them out of the linear mode. As a result, the attacker hears only noise instead of the desired information. To ensure that interference does not affect the quality of the speech signal, it is compensated before being sent to the transmitting telephone and is selected from signals that are attenuated before they arrive at the telephone exchange or are filtered from the useful signal. Active jamming equipment is highly effective at protecting telephone lines from almost all types of listening devices. Among them: an electronic module for integrated protection of a wired telephone line "Sprut" and "Sonata-03M", noise generators for standard telephone lines SEL SP-17/T, "Cicada", "Gnome", "Proton", etc.

Telephone line analyzers They are designed to search for channels for intercepting telephone conversations and identifying cases of unauthorized connection to a telephone line. There are two main classes of analyzers. The first includes devices that detect changes in telephone line parameters during unauthorized connection to it: the direct current component, the active and reactive components of the telephone line impedance. Changes in these characteristics are recorded and serve as the basis for making decisions about the possibility of unauthorized connection to the telephone line.

The simplest analyzers - telephone line monitoring devices KTL-2 and TPU-5 - allow you to determine resistive changes in line parameters and measure the voltage in them. More complex analyzers make it possible to identify the approximate location of connection to the line, as well as facts of contactless connection: telephone line analyzers ALT-01, AT-23, "Olkha", "Bager-01", MT205, search device RT 030, cable radar "Vector" , nonlinear location systems and others. The second class consists of software and hardware for radio monitoring and scanning, the operating principle of which is based on the control and analysis of radio emissions by means of interception and connection to telephone lines. Such devices make it possible to effectively identify “bugs”. There are monitoring tools - from relatively cheap D-006 field indicators to universal monitoring systems for technical channels of information leakage "Krona-6000" and expensive AR-3000 scanners. The weak point of telephone line analyzers is the high probability of false alarms, as well as the inability to determine all types of connections to the telephone line.

Therefore, so-called complexes for monitoring and analyzing the results of monitoring signals from unauthorized access devices have been created.

Such complexes can solve the following problems:

Detection of emissions from unauthorized access devices and their localization;

Detection of side electromagnetic radiation and interference;

Assessing the effectiveness of using technical means of protecting speech information;

Monitoring compliance with restrictions on the use of radio-electronic equipment;

Assessment of the type and parameters of the original information flow contained in the processed analog signal;

Maintaining a database of signal parameters and their sources.

Programs for detecting means of collecting speech information are installed on a PC. They implement most radio bookmark detection algorithms. Software and hardware systems for radio monitoring: the universal program for detecting means of covert information collection "Filin", the universal monitoring program Sedif Plus, the professional monitoring program Sedif Pro, the system for collecting and processing data and monitoring measurements "Regulation-P".

IN Lately multifunctional devices appeared. For example, the Barrier-4 telephone line security system provides:

Monitoring the state of the electrical network and detecting high-frequency signals in it;

Possibility of connecting scanning and analyzing devices;

Suppression of listening and sound recording devices;

Indication of connection of information retrieval devices, etc.

Telephone conversation protection devices are multifunctional from listening and recording of the "Procrustes" series, comprehensive protection of a wire line from unauthorized removal of information "Octopus", comprehensive protection of the "Storm" telephone line, as well as the above-mentioned telephone line security system of the "Barrier" series, etc.

MEANS OF ACOUSTIC PROTECTION OF SPEECH INFORMATION

To ensure the confidentiality of telephone conversations, it is not enough to protect the information on the telephone line. There is a very high probability that speech information will be captured before the sound vibrations are converted into electrical signals in the handset. Protection at this stage is called acoustic. It is based on the use of speech masking with acoustic masking noise, operating in the speech frequency band and having a “smooth” spectral characteristic. There are three main groups of means of acoustic protection of speech information. The first includes producers of barrage acoustic interference, which are used for acoustic protection of premises and, as a rule, are used with vibration protection equipment: “Baron”, “Rustle”, “Storm”. They allow you to protect information from interception using stethoscopes and laser microphones via vibroacoustic propagation channels. The complex consists of a noise generator and several radio receivers, which, through mixing, significantly reduce the likelihood of isolating a speech signal from a noisy one. The second group includes acoustic noise generators, which are located near the place of telephone conversations and with their noise mask the speech of the participants in the negotiations. In this case, the speaker speaking into the handset is not protected from the effects of acoustic noise. Such devices include the ANG-2000 acoustic noise generator (it creates interference with a power of up to 2 W in the 2 - 10 kHz band). To protect against generator noise, intercom headsets (TF-011D, OKP-6, etc.) are used. The third group of means is represented by acoustic maskers: masking noise is supplied from the generator simultaneously to the electroacoustic emitter and to the input of the signal mixer filter, the second input of which is supplied with a signal from the output of the receiving microphone. In the acoustic signal mixer, the noise component of the signal is compensated, and the cleaned speech enters the telephone line. The masker is implemented in the CNDS acoustic protection equipment for confidential conversations and provides suppression of masking noise in the signal to a depth of 26 - 30 dB. INFORMATION CONVERSION OF SPEECH SIGNALS AND MESSAGES Scramblers became the first hardware and software devices for protecting speech information when transmitted in analog form in a telephone channel. In analog scrambling, the original speech signal is converted in such a way that the linear signal on the telephone line becomes unintelligible, although it occupies the same frequency band. The speech signal can be subjected to frequency inversion, frequency and time permutation, and in addition, mosaic transformation (frequency inversion and time permutation). Analog scrambling provides only temporary stability of speech information. In this case, resistance is understood as the number of operations (transformations) that are necessary to decipher a certain speech message without knowing the keys. However, having a sufficiently powerful set of measuring and converting equipment, it is possible to restore the original speech signal with acceptable quality. To increase the stability of speech signal conversion, cryptoblocks are introduced into scramblers to control scrambling. Such scramblers on the transmitting and receiving sides must ensure synchronization of the devices before starting work and maintain it during a telephone conversation. Cryptographic scrambling control results in a signal delay, which creates a so-called echo in the telephone set. The more powerful the cryptographic algorithm, the worse the quality of the speech signal on the receiving side of the telephone line. To eliminate this drawback, keys with a length of about 30 bits are used for a symmetric key system and about 100 bits in an asymmetric key system. key system . There is a large selection of various scramblers: telephone/fax scramblers of the SCR-M 1.2, “Selena”, “Orekh-A”, “Line-1” series, etc. Significantly higher security of speech information can be obtained when transmitting it in a channel communications in digital form using scramblers, but not analog, but digital. Encryption and decoding of speech information is carried out according to one algorithm. The use of speech information encoders is possible when they are synchronized on the transmitting and receiving sides of the telephone channel: on the transmitting side, synchronization bits are added to the information flow, which are allocated on the receiving side to synchronize devices, or time pulse generators and memory synchronization circuits are used to synchronize the encoders . A significant disadvantage of encryptors is their instability to falsification of speech information. In addition, with the advent of packet-switching networks, it became possible to use block encryption to protect voice information, which has significantly greater strength compared to streaming encryption. Guaranteed strength of speech information protection can be achieved by encrypting speech audio codes. Digitization of an analog speech signal, compression and encoding of a digital signal is carried out using a vocoder (from English voice coder). The operating principle of vocoders is based on the digitization of a speech signal by recognizing sounds and encoding them at a low speed (1 - 2 kbit/s), which allows one to accurately represent any sound in digital form. If a cryptographic transformation is applied to a digital stream, the result is encoded information of guaranteed strength, which is practically impossible to decrypt without knowledge of the keys and the cryptographic algorithms used. Most vocoders and scramblers use a public Diffie-Hellman cryptographic key distribution system and digital stream encryption based on various algorithms, including triple DES, CAST-128, Blowfish, IDEA and Russian GOST 28147-89. The disadvantage of vocoders is some signal delay, as well as distortion of speech information. One of the best is considered to be a codec that implements the CELP algorithm, which is used in a modified form in the Referent equipment. Commercial vocoders are relatively expensive, but their number is growing every year: Voice Coder-2400 telephone, Orekh-4130 telephone accessory for protecting speech information, SKR-511 Referent telephone conversation security devices. PROTECTION OF VOICE INFORMATION IN IP-TELEPHONEY In IP-telephony, there are two main ways to transmit packets with voice information over the network: via the Internet and through corporate networks + dedicated channels. There are few differences between these methods, however, in the second case, better sound quality and a small fixed delay of voice information packets when transmitted over an IP network are guaranteed. To protect voice information transmitted over IP networks, cryptographic algorithms are used to encrypt source packets and messages, which, generally speaking, make it possible to ensure guaranteed stability of IP telephony. There are effective cryptographic algorithms implemented on a PC, which, when using 256-bit secret and 1024-bit public encryption keys (for example, according to GOST 28147-89), make it practically impossible to decrypt a speech packet. However, when using such algorithms in IP telephony, several important factors should be taken into account, which can negate the capabilities of many modern means of cryptographic information protection. To ensure acceptable sound quality on the receiving side when transmitting voice packets over an IP network, the delay in their delivery from the receiving side should not exceed 250 ms. To reduce latency, the digitized speech signal is compressed and then encrypted using stream encryption algorithms and IP network transmission protocols. Another problem of secure IP telephony is the exchange of cryptographic encryption keys between network subscribers. Typically, public key cryptographic protocols are used using the Diffie-Hellman protocol, which prevents someone who intercepts a conversation from gaining any useful information about keys and at the same time allows the parties to exchange information to form a common session key. This key is used to encrypt and decrypt the resource stream. In order to minimize the possibility of interception of encryption keys, various subscriber and key authentication technologies are used. All cryptographic protocols and the voice stream compression protocol are selected by IP telephony programs dynamically and transparently to the user, providing him with a natural interface similar to a regular telephone. Implementing efficient cryptographic algorithms and ensuring audio quality requires significant computing resources. In most cases, these requirements are met by using fairly powerful and productive computers, which, as a rule, do not fit into the body of a telephone. But computer-to-computer exchange of voice information does not always suit IP telephony users. It is much more convenient to use a small, or better yet, mobile IP telephony device. Such devices have already appeared, although they provide voice stream encryption strength much lower than computer IP telephony systems. In such telephones, the GSM algorithm is used to compress the speech signal, and encryption is carried out using the Wireless Transport Layer Security (WTLS) protocol, which is part of the Wireless Application Protocol (WAP) implemented in networks mobile communications. According to experts, the future lies with such telephones: small, mobile, reliable, with guaranteed durability of speech information protection and high quality

Moscow Department of Education

State Autonomous Educational Institution

secondary vocational education in Moscow

Polytechnic College No. 8

named twice Hero Soviet Union I.F. Pavlova

COURSE PROJECT

SPECIALTY - 090905

"Organization and technology of information security"

on the topic: Protection of acoustic (speech) information from leakage through technical channels

Course project completed

student group: 34OB(s)

Teacher: V.P. Zverev

Moscow 2013

Introduction

Chapter 1. Theoretical justification of methods and means of protecting speech information from leakage through technical channels

1 Acoustic information

2 Technical channels of information leakage

3 Basic ways to obtain acoustic information

Chapter 2. Practical justification of methods and means of protecting speech information from leakage through technical channels

1 Organizational measures for the protection of speech information

2 Equipment for searching technical means of reconnaissance

3 Technical means of protecting acoustic information from leakage through technical channels

Chapter 3. Feasibility study

Chapter 4. Safety precautions and workplace organization

1 Explanation of requirements for premises and workplaces

Conclusion

Bibliography

Introduction

According to trends in the development of society, the most common resource is information, and, consequently, its value is constantly increasing. “Whoever owns the information owns the world.” This undoubtedly has an essence that expresses the current situation in the world. Since the disclosure of some information often leads to negative consequences for its owner, the issue of protecting information from unauthorized receipt is becoming increasingly acute.

Since for every defense there is a way to overcome it, to ensure proper information security it is necessary to constantly improve methods.

Information carried by a speech signal or speech information receives worthy attention of the attacking side. In the general case, speech information is a set consisting of semantic, personal, behavioral, etc. information. As a rule, semantic information is of greatest interest.

The problem of protecting confidential negotiations is solved comprehensively using various types of measures, including the use of technical means, this happens as follows. The fact is that the primary carriers of speech information are acoustic vibrations of the air environment created by the articulatory tract of the negotiator. By natural or artificial means, vibration, magnetic, electrical and electromagnetic oscillations in various frequency ranges become secondary carriers of speech information, which “remove” confidential information from the meeting room. To eliminate this fact, these oscillations are masked by similar oscillations, which are masking signals in “suspicious” or identified frequency ranges. In this regard, known technical channels of speech information leakage, such as cable networks for various purposes, pipelines, enclosing building structures, windows and doors, and stray electromagnetic radiation (ESEM), are “closed” on an ongoing basis by various technical means.

This entire set of measures requires significant financial costs, both one-time (during the construction or refurbishment of office premises in order to meet information security requirements) and ongoing (for carrying out the above measures and for updating the fleet of monitoring equipment). These costs can reach several tens or even hundreds of thousands of dollars, depending on the importance of confidential information and the financial capabilities of office premises owners.

The purpose of this thesis is a theoretical and practical consideration of methods and means of protecting acoustic (speech) information from leakage through technical channels.

Objectives of this course project:

· Identification of leakage channels and unauthorized access to resources

· Technical channels of information leakage

· Means of active protection of speech information from leakage through technical channels

The object of the study is the classification of methods and means of protecting speech information from leakage through technical channels

The subject of the research is organizational measures for the protection of speech information, equipment for searching for intelligence means and technical means protection of acoustic information.

acoustic protection information

Chapter 1. Theoretical justification of methods and means of protecting speech information from leakage through technical channels

1 Acoustic information

Protected speech (acoustic) information includes information that is proprietary and subject to protection in accordance with the requirements of legal documents or requirements established by the owner of the information. This is, as a rule, restricted access information containing information classified as state secrets, as well as information of a confidential nature.

To discuss restricted access information (meetings, discussions, conferences, negotiations, etc.), special rooms are used (offices, assembly halls, conference rooms, etc.), which are called dedicated rooms (VP). To prevent the interception of information from these premises, as a rule, special means of protection are used, therefore, dedicated premises are in some cases called protected premises (SP).

As a rule, auxiliary technical means and systems (HTSS) are installed in dedicated premises:

City automatic telephone communication;

Data transmission in a radio communication system;

Security and fire alarm systems;

Alerts and alarms;

Air conditioning;

Wired radio broadcasting network and reception of radio and television programs (subscriber loudspeakers, radio broadcasting equipment, televisions and radios, etc.);

Electronic office equipment;

Electric clock equipment;

Instrumentation equipment, etc.

The allocated premises are located within the controlled zone (CA), which means a space (territory, building, part of a building) in which the uncontrolled presence of unauthorized persons (including visitors to the organization) is excluded, as well as Vehicle. The border of the controlled zone may be the perimeter of the protected territory of the organization, the enclosing structures of the protected building or the protected part of the building, if it is located in an unprotected area. In some cases, the boundary of the controlled area may be the enclosing structures (walls, floor, ceiling) of the allocated room.

Protection of speech (acoustic) information from leakage through technical channels is achieved by carrying out organizational and technical measures, as well as identifying portable electronic information interception devices (embedded devices) installed in designated premises.

2 Technical channels of information leakage

Acoustic channel

The acoustic information leakage channel is implemented as follows:

· eavesdropping on conversations in open areas and indoors, being nearby or using directional microphones (there are parabolic, tubular or flat). The directionality is 2-5 degrees, the average range of the most common - tubular - is about 100 meters. With good climatic conditions in open areas, a parabolic directional microphone can operate at a distance of up to 1 km;

· secret recording of conversations using a voice recorder or tape recorder (including voice-activated digital voice recorders);

· eavesdropping on conversations using remote microphones (the range of radio microphones is 50-200 meters without repeaters).

Microphones used in radio devices can be built-in or remote and have two types: acoustic (sensitive mainly to the action of sound vibrations in the air and designed to intercept voice messages) and vibration (converting vibrations that occur in various rigid structures into electrical signals).

Acoustoelectric channel

Acoustoelectric information leakage channel, the features of which are:

· ease of use (power supply is available everywhere);

· no problems with power supply to the microphone;

· the ability to retrieve information from the power supply network without connecting to it (using electromagnetic radiation from the power supply network). Reception of information from such “bugs” is carried out by special receivers connected to the power network within a radius of up to 300 meters from the “bug” along the length of the wiring or to the power transformer serving the building or complex of buildings;

· possible interference on household appliances when using the electrical network to transmit information, as well as poor quality of the transmitted signal when household appliances operate a lot.

Prevention:

· transformer isolation is an obstacle to further transmission of information through the power supply network;

Telephone channel

A telephone information leakage channel for eavesdropping on telephone conversations (as part of industrial espionage) is possible:

· galvanic recording of telephone conversations (by contact connection of listening devices anywhere in the subscriber room telephone network). Determined by deterioration of audibility and the appearance of interference, as well as with the help of special equipment;

· telephone-location method (by high-frequency imposition). A high-frequency tone signal is supplied through the telephone line, which affects the nonlinear elements of the telephone set (diodes, transistors, microcircuits), which are also affected by the acoustic signal. As a result, a high-frequency modulated signal is formed in the telephone line. Eavesdropping can be detected by the presence of a high-frequency signal in the telephone line. However, the range of such a system is due to the attenuation of the RF signal in a two-wire system. the line does not exceed one hundred meters. Possible counteraction: suppression of high-frequency signal in the telephone line;

· inductive and capacitive method of secretly recording telephone conversations (contactless connection).

Inductive method - due to electromagnetic induction that occurs during telephone conversations along the telephone line wire. A transformer is used as a receiving device for retrieving information, the primary winding of which covers one or two wires of the telephone line.

Capacitive method - due to the formation of an electrostatic field on the plates of the capacitor, changing in accordance with changes in the level of telephone conversations. Used as a telephone conversation receiver capacitive sensor, made in the form of two plates that fit tightly to the telephone line wires.

Eavesdropping on conversations indoors using telephones is possible in the following ways:

· low-frequency and high-frequency method of recording acoustic signals and telephone conversations. This method is based on connecting listening devices to the telephone line, which are converted by a microphone sound signals transmitted over a telephone line at high or low frequency. Allows you to listen to a conversation both when the handset is raised and lowered. Protection is carried out by cutting off the high-frequency and low-frequency components in the telephone line;

· use of telephone remote listening devices. This method is based on installing a remote listening device in elements of the subscriber telephone network by parallel connection it to the telephone line and remote activation. A remote telephone eavesdropping device has two deconstructing properties: at the time of eavesdropping, the subscriber's telephone set is disconnected from the telephone line, and also when the telephone is on-hook and the eavesdropping device is turned on, the supply voltage of the telephone line is less than 20 Volts, while it should be 60.

3 Basic ways to obtain acoustic information

The main reasons for information leakage are:

Failure of personnel to comply with the norms, requirements, and operating rules of the NPP;

Errors in the design of NPPs and NPP protection systems;

Conducting technical and intelligence intelligence by the opposing side.

In accordance with GOST R 50922-96, three types of information leakage are considered:

Disclosure;

Unauthorized access to information;

Obtaining protected information by intelligence services (both domestic and foreign).

Disclosure of information means the unauthorized delivery of protected information to consumers who do not have the right to access the protected information.

Unauthorized access means the receipt of protected information by an interested subject in violation of the rights or rules of access to protected information established by legal documents or the owner, owner of the information. In this case, the interested party exercising unauthorized access to information may be: the state, entity, a group of individuals, including a public organization, an individual individual.

Obtaining protected information by intelligence services can be carried out using technical means (technical intelligence) or undercover methods (undercover intelligence).

Composition of information leakage channels

Source KUI	Name of KUI	Description
Telephone lines Radiotelephone	Electroacoustic, PEMIN
City and local radio broadcast	Electroacoustic, PEMIN	Information leakage due to acoustoelectric conversion in the radio broadcast line receiver; - Information leakage due to modulation of EM fields generated by the operation of household appliances by a useful signal.
PC with full configuration		Information leakage due to modulation of EM fields generated by the operation of household appliances by a useful signal.
Photo-optical detectors	Electroacoustic, PEMIN	Information leakage due to acoustoelectric conversion in the radio broadcast line receiver; - Information leakage due to modulation of EM fields generated by the operation of household appliances by a useful signal.
Heating and ventilation system	Acoustic	Information leakage due to weak acoustic insulation (cracks, leaks, holes). Such leaks include: - cracks near embedded cable pipes, - ventilation, door leaks and door frame. - Transfer of information through vibration through heating risers.
Power supply system	Electroacoustic, PEMIN	Information leakage due to acoustoelectric conversion in the radio broadcast line receiver; - Information leakage due to modulation of EM fields generated by the operation of household appliances by a useful signal.
3G mobile phone	Acoustic	Leak of information via radio channel.
Ceilings	Acoustic	Membrane energy transfer of speech signals through partitions due to low mass and weak signal attenuation.
	Vibrating	Information leakage by removing a useful signal from surfaces that vibrate during a conversation.
Grounding system	Electroacoustic	Information leakage due to acoustoelectric conversion in the radio broadcast line receiver.

Of all the possible channels of information leakage, technical channels of information leakage are the most attractive to attackers; therefore, it is necessary to organize concealment and protection against information leakage primarily through these channels. Since organizing the concealment and protection of acoustic information from leakage through technical channels is quite an expensive undertaking, it is necessary to conduct a detailed study of all channels, and apply technical means of protection precisely in those places where it is impossible to do without them.

Chapter 2. Practical justification of methods and means of protecting speech information from leakage through technical channels

1 Organizational measures for the protection of speech information

The main organizational measures to protect speech information from leakage through technical channels include:

Selection of premises for confidential negotiations (dedicated premises);

Use of certified auxiliary technical means and systems (VTSS) in airspace;

Establishment of a controlled zone around the airspace;

Dismantling of unused VTSS, their connecting lines and extraneous conductors in the VP;

Organization of regime and access control in the VP;

Disabling confidential conversations of unprotected VTSS.

Premises in which confidential negotiations are expected to be conducted must be selected taking into account their sound insulation, as well as the enemy’s ability to intercept speech information via acousto-vibration and acousto-optical channels. As allocated, it is advisable to choose premises that do not have common enclosing structures with premises belonging to other organizations, or with premises to which there is uncontrolled access by unauthorized persons. If possible, the windows of designated premises should not overlook parking areas, as well as nearby buildings from which reconnaissance using laser acoustic systems is possible.

If the border of the controlled zone is the enclosing structures (walls, floor, ceiling) of the allocated premises, a temporary controlled zone can be established for the period of confidential events, which excludes or significantly complicates the possibility of interception of voice information.

Only certified technical means and systems should be used in designated premises, i.e. past special technical checks for the possible presence of embedded embedded devices, special studies for the presence of acoustoelectric information leakage channels and having certificates of compliance with information security requirements in accordance with regulatory documents FSTEC of Russia.

All auxiliary technical means not used to ensure confidential negotiations, as well as extraneous cables and wires passing through the allocated premises must be dismantled.

Uncertified technical equipment installed in designated premises must be disconnected from connecting lines and power sources when conducting confidential negotiations.

During off-duty hours, allocated premises must be closed, sealed and placed under guard. During official hours, employees' access to these premises should be limited (according to lists) and controlled (visitation records). If necessary, these premises can be equipped with access control and management systems.

All work on IP protection (at the stages of design, construction or reconstruction, installation of equipment and information security equipment, certification of IP) is carried out by organizations licensed to operate in the field of information security.

When a VP is put into operation, and then periodically, it must be certified according to information security requirements in accordance with the regulatory documents of the FSTEC of Russia. Special examinations should also be carried out periodically.

In most cases, organizational measures alone cannot ensure the required efficiency of information protection and it is necessary to carry out technical measures to protect information. A technical event is an information protection event that involves the use of special technical means, as well as the implementation of technical solutions. Technical measures are aimed at closing channels of information leakage by reducing the signal-to-noise ratio in places where portable acoustic reconnaissance equipment or their sensors may be located to values ​​that ensure the impossibility of identifying information signal means of reconnaissance. Depending on the means used, technical methods of protecting information are divided into passive and active.

Passive methods of information protection are aimed at:

· weakening of acoustic and vibration signals to values ​​that ensure the impossibility of their isolation by means of acoustic reconnaissance against the background of natural noise in their places possible installation;

· weakening of information electrical signals in the connecting lines of auxiliary technical means and systems that arose as a result of acousto-electric transformations of acoustic signals, to values ​​that ensure the impossibility of their isolation by reconnaissance means against the background of natural noise;

· exclusion (weakening) of the passage of “high-frequency imposition” signals in HTSS, which incorporate electroacoustic transducers (having a microphone effect);

· weakening of radio signals transmitted by embedded devices to values ​​that ensure the impossibility of their reception in places where receiving devices can be installed;

· weakening of signals transmitted by embedded devices via a 220 V power supply network to values ​​that ensure the impossibility of their reception in places where receiving devices can be installed

Rice. 1 Classification of passive methods of protection

Speech (acoustic) signals are weakened by soundproofing rooms, which is aimed at localizing the sources of acoustic signals inside them.

Special inserts and gaskets are used for vibration isolation of heat, gas, water supply and sewerage pipes extending beyond the controlled area

Fig.2. Installation of special tools

In order to close acoustoelectromagnetic channels of speech information leakage, as well as information leakage channels created by hidden installation of embedded devices in premises with information transmission via radio channel, various methods of shielding selected premises are used

Installation of special low-frequency filters and limiters in VTSS connecting lines extending beyond the controlled area is used to eliminate the possibility of intercepting speech information from designated premises via passive and active acoustoelectric information leakage channels

Special low-frequency filters of the FP type are installed in the power supply line (socket and lighting network) of a dedicated room in order to exclude the possible transmission of information intercepted by network bookmarks through them (Fig. 4). For these purposes, filters with a cutoff frequency fgp ≤ 20...40 kHz and an attenuation of at least 60 - 80 dB are used. Filters must be installed within the controlled area.

Fig.3. Installation of a special device - “Granit-8”

Rice. 4. Installation of special filters (FP type).

If it is technically impossible to use passive means of protecting premises or if they do not provide the required sound insulation standards, active methods of protecting speech information are used, which are aimed at:

· creation of masking acoustic and vibration noise in order to reduce the signal-to-noise ratio to values ​​that ensure the impossibility of identifying speech information by means of acoustic reconnaissance in the places of their possible installation;

· creation of masking electromagnetic interference in VTSS connecting lines in order to reduce the signal-to-noise ratio to values ​​that ensure the impossibility of isolating an information signal by reconnaissance means in possible places their connections;

· suppression of sound recording devices (dictaphones) in recording mode;

· suppression of receiving devices that receive information from embedded devices via a radio channel;

· suppression of receiving devices that receive information from embedded devices via a 220 V electrical network

Fig.5. Classification of active methods of protection

Acoustic masking is effectively used to protect speech information from leakage through a direct acoustic channel by suppressing acoustic interference (noise) of microphones of reconnaissance equipment installed in such structural elements of protected premises as a door vestibule, ventilation duct, space behind a suspended ceiling, etc.

Vibroacoustic masking is used to protect speech information from leakage through acousto-vibration (Fig. 6) and acousto-optical (optoelectronic) channels (Fig. 7) and consists of creating vibration noise in elements of building structures, window glass, utilities, etc. Vibroacoustic camouflage is effectively used to suppress electronic and radio stethoscopes, as well as laser acoustic reconnaissance systems

Rice. 6.Creation of vibration interference

The creation of masking electromagnetic low-frequency interference (low-frequency masking interference method) is used to eliminate the possibility of intercepting speech information from designated premises via passive and active acoustoelectric information leakage channels, suppressing wired microphone systems that use VTSS connecting lines to transmit information at low frequencies, and suppressing acoustic jamming "telephone ear" type.

Most often, this method is used to protect telephone sets that contain elements that have a “microphone effect”, and consists of supplying a masking signal (most often of the “white noise” type) of the speech frequency range (usually , the main interference power is concentrated in the frequency range of a standard telephone channel: 300 - 3400 Hz) (Fig. 8).

Rice. 7. Interference

The creation of masking high-frequency (frequency range from 20 - 40 kHz to 10 - 30 MHz) electromagnetic interference in the power supply lines (socket and lighting network) of a dedicated room is used to suppress devices receiving information from network bookmarks (Fig. 9).

The creation of spatial masking high-frequency (frequency range from 20 - 50 kHz to 1.5 - 2.5 MHz)* electromagnetic interference is mainly used to suppress devices for receiving information from radio bombs (Fig. 10).

Rice. 8. Creation of high frequency interference

Soundproofing of premises

Sound insulation (vibration insulation) of dedicated (protected) premises (VP) is the main in a passive way protection of speech information and is aimed at localizing sources of acoustic signals inside them. It is carried out in order to exclude the possibility of eavesdropping on conversations taking place in a dedicated room, as without the use of technical means by unauthorized persons (visitors, technical staff), as well as by employees of the organization who are not allowed to the information being discussed, when they are in the corridors and adjacent to the allocated rooms (unintentional listening), and by the enemy through direct acoustic (through cracks, windows, doors, technological openings, ventilation ducts, etc.) etc.), acousto-vibration (through enclosing structures, utility pipes, etc.) and acousto-optical (through window glass) technical channels of information leakage using portable means of acoustic (speech) reconnaissance.

As an indicator for assessing the effectiveness of sound insulation of allocated premises, verbal speech intelligibility is used, characterized by the number of correctly understood words and reflecting the qualitative area of ​​comprehensibility, which is expressed in terms of the details of the compiled certificate about the conversation intercepted using technical intelligence means.

The process of speech perception in noise is accompanied by losses constituent elements voice message. In this case, speech intelligibility will be determined not only by the level of the speech signal, but also by the level and nature of external noise at the location of the reconnaissance equipment sensor.

The criteria for the effectiveness of speech information protection largely depend on the goals pursued in organizing the protection, for example: to hide the semantic content of an ongoing conversation, to hide the topic of an ongoing conversation, or to hide the very fact of negotiations.

Practical experience shows that drawing up a detailed report on the content of an intercepted conversation is impossible when verbal intelligibility is less than 60 - 70%, and a brief summary is impossible when verbal intelligibility is less than 40 - 60%. When verbal intelligibility is less than 20 - 40%, it is significantly difficult to establish even the subject of an ongoing conversation, and when verbal intelligibility is less than 10 - 20%, this is practically impossible even when using modern noise reduction methods.

Considering that the level of the speech signal in a dedicated room can range from 64 to 84 dB, depending on the level of acoustic noise at the location of the reconnaissance facility and the category of the dedicated room, it is easy to calculate the required level of its sound insulation to ensure effective protection of speech information from leakage according to all possible technical channels.

Sound insulation of premises is ensured with the help of architectural and engineering solutions, as well as the use of special construction and finishing materials.

When an acoustic wave falls on the boundary of surfaces with different specific densities, most of the incident wave is reflected. A smaller part of the wave penetrates the material of the soundproofing structure and propagates through it, losing its energy depending on the length of the path and its acoustic properties. Under the influence of an acoustic wave, the soundproofing surface undergoes complex vibrations, which also absorb the energy of the incident wave.

The nature of this absorption is determined by the ratio of the frequencies of the incident acoustic wave and the spectral characteristics of the surface of the soundproofing device.

When assessing the sound insulation of designated premises, it is necessary to separately consider the sound insulation of: the enclosing structures of the room (walls, floor, ceiling, windows, doors) and engineering support systems (supply and exhaust ventilation, heating, air conditioning).

2 Equipment for searching technical means of reconnaissance

Multifunctional search device ST 033 "Piranha"033 "Piranha" is designed to carry out operational measures to detect and localize technical means of secretly obtaining information, as well as to identify natural and artificially created channels of information leakage.

The product consists of a main control and display unit, a set of converters and allows operation in the following modes:

· high-frequency detector-frequency meter;

Microwave detector (Together with ST03.SHF)

· Wire line analyzer;

· IR radiation detector;

· detector of low-frequency magnetic fields;

· differential low-frequency amplifier (together with ST 03.DA);

· vibroacoustic receiver;

· acoustic receiver

Figure 9 - Multifunctional search device ST 033 "Piranha"

The transition to any of the modes is carried out automatically when the corresponding converter is connected. Information is displayed on a backlit graphic LCD display; acoustic control is carried out through special headphones or through a built-in loudspeaker.

It is possible to store up to 99 images in volatile memory.

Indication of incoming low-frequency signals is provided in oscilloscope or spectrum analyzer modes with indication of numerical parameters.

The ST 033 "Piranha" provides contextual help on the display depending on the operating mode. You can choose Russian or English.033 "Piranha" is made in a wearable version. To carry and store it, a special bag is used, designed for compact and convenient stowage of all elements of the kit.

Using ST 033 "Piranha" it is possible to solve the following control and search tasks:

Identification of the fact of operation (detection) and localization of the location of radio-emitting special technical means that create potentially dangerous radio emissions from the point of view of information leakage. These means primarily include:

· radio microphones;

· telephone radio repeaters;

radio stethoscopes;

· hidden video cameras with a radio channel for transmitting information;

· technical means of spatial high-frequency irradiation systems in the radio range;

· radio beacons for tracking systems for the movement of objects (people, vehicles, cargo, etc.);

· unauthorized cell phones of GSM, DECT standards, radio stations, cordless phones.

· devices that use data transmission channels using BLUETOOTH and WLAN standards to transmit data.

2. Detection and localization of the location of special technical means that work with radiation in the infrared range. These means primarily include:

· embedded devices for obtaining acoustic information from premises with its subsequent transmission via a channel in the infrared range;

· technical means of spatial irradiation systems in the infrared range.

3. Detection and localization of the location of special technical means that use wire lines for various purposes to obtain and transmit information, as well as technical means of information processing that create induction of informative signals onto nearby wire lines or the flow of these signals into the lines of the power supply network. Such means may be:

· embedded devices that use network lines to transmit intercepted information alternating current 220V and capable of operating at frequencies up to 15 MHz;

· PCs and other technical means of producing, reproducing and transmitting information;

· technical means of linear high-frequency imposition systems operating at frequencies above 150 kHz;

· embedded devices that use subscriber telephone lines, lines of fire and fire protection systems to transmit intercepted information burglar alarm with a carrier frequency above 20 kHz.

4. Detection and localization of the location of sources of electromagnetic fields with a predominance (presence) of the magnetic component of the field, routes for laying hidden (unmarked) electrical wiring, potentially suitable for installing embedded devices, as well as research of technical means that process speech information. Such sources and technical means usually include:

· output transformers of audio frequency amplifiers;

· dynamic loudspeakers of acoustic systems;

· electric motors of tape recorders and voice recorders;

5. Identification of the most vulnerable places from the point of view of the occurrence of vibroacoustic channels of information leakage.

Identification of the most vulnerable places from the point of view of the occurrence of acoustic information leakage channels.

Vibroacoustic receiver mode

In this mode, the product receives from an external vibroacoustic sensor and displays the parameters of low-frequency signals in the range from 300 to 6000 Hz.

The state of vibroacoustic protection of premises is assessed both quantitatively and qualitatively.

A quantitative assessment of the protection status is carried out based on the analysis of an oscillogram automatically displayed on the display screen, displaying the shape of the received signal and the current value of its amplitude.

A qualitative assessment of the state of protection is based on direct listening to the received low-frequency signal and analysis of its volume and timbre characteristics. For this, either the built-in loudspeaker or headphones are used.

Specifications

Acoustic receiver mode

In this mode, the product provides reception to an external remote microphone and displays the parameters of acoustic signals in the range from 300 to 6000 Hz.

The state of sound insulation of premises and the presence of vulnerable places in them from the point of view of information leakage are determined both quantitatively and qualitatively.

Quantitative assessment of the state of sound insulation of premises and identification of possible channels of information leakage are carried out based on the analysis of an oscillogram automatically displayed on the display screen, reflecting the shape of the received signal and the current value of its amplitude.

Qualitative assessment is based on direct listening to the received acoustic signal and analysis of its volume and timbre characteristics. For this, either the built-in loudspeaker or headphones are used.

Specifications

General technical characteristics of ST 033 "PIRANHA"

High frequency detector-frequency meter
Operating frequency range, MHz
Sensitivity, mV	< 2 (200МГц-1000МГц) 4 (1000МГц-1600МГц) 8 (1600МГц-2000МГц)
Dynamic range, dB
Frequency meter sensitivity, mV	<15 (100МГц-1200МГц)
Frequency measurement accuracy, %
Wire Line Scanning Analyzer
Scan range, MHz
Sensitivity, at s/n 10 dB, mV
Scan step, kHz
Scanning speed, kHz
Bandwidth, kHz
Adjacent channel selectivity, dB
Detection Mode
Permissible network voltage, V
IR Radiation Detector
Spectral range, nm
Threshold sensitivity, W/Hz2
Field of view angle, degrees.
Frequency band, MHz
LF magnetic field detector
Frequency range, kHz
Threshold sensitivity, A/(m x Hz2)
Vibroacoustic receiver
Sensitivity, V x sec2/m
Inherent noise in the band 300Hz-3000Hz, µV
Acoustic receiver
Sensitivity, mV/Pa
Frequency range, Hz
Oscilloscope and spectrum analyzer
Bandwidth, kHz
Input sensitivity, mV
Measurement error, %
Waveform output speed, s
Spectrogram output speed, s
Indication
Liquid crystal graphic display with a resolution of 128x64 pixels with adjustable backlight
Supply voltage, V	6(4 batteries or AA batteries)/220
Maximum current consumption, no more than mA
Current consumption in operating mode, no more than mA
Dimensions, mm
Main unit
Packing bag
Main unit

Delivery contents

Name	Quantity, pcs
1. Main control, processing and display unit
2. Active HF antenna
3. Wire Line Scanning Analyzer Adapter
4. Nozzle type "220"
5. Crocodile type nozzle
6. Needle type nozzle
7. Magnetic sensor
8. IR sensor
9.Acoustic sensor
10. Vibroacoustic sensor
11. Telescopic antenna
12. Headphones
13. AA battery
14. Shoulder strap
15. Main unit stand
16. Power supply
17. Bag - packaging
18. Technical description and operating instructions

3 Technical means of protecting acoustic information from leakage through technical channels

Spatial noise generators

The GROM-ZI-4 noise generator is designed to protect premises from information leakage and prevent the removal of information from personal computers and PC-based local area networks. Universal noise generator range 20 - 1000 MHz. Operating modes: “Radio channel”, “Telephone line”, “Power network”

Main functionality of the device:

· Generating interference over the airwaves, telephone lines and electrical networks to block unauthorized devices transmitting information;

· Masking of side electromagnetic radiation from PCs and LANs;

· No need for adjustment to specific application conditions.

Noise generator "Grom-ZI-4"

Generator technical data and characteristics

· Field strength of interference generated over the air relative to 1 µV/m

· The voltage of the signal generated via the electrical network is relative to 1 µV in the frequency range 0.1-1 MHz - at least 60 dB;

· Signal generated via telephone line - pulses with a frequency of 20 kHz and an amplitude of 10V;

· Power supply 220V 50Hz.

The Grom 3I-4 generator is part of the Grom 3I-4 system together with the Si-5002.1 discone antenna

Parameters of the Si-5002.1 discone antenna:

· Operating frequency range: 1 - 2000 MHz.

· Vertical polarization.

· Directional pattern - quasi-circular.

· Dimensions: 360x950 mm.

The antenna can be used as a receiving antenna as part of radio monitoring complexes and in studying the strength of noise and pulse electric fields of radio signals with measuring receivers and spectrum analyzers

Telephone line protection equipment

"Lightning"

“Lightning” is a means of protection against unauthorized eavesdropping of conversations both on the telephone and indoors using devices operating on wire lines or power lines.

The operating principle of the device is based on the electrical breakdown of radioelements. When you press the “Start” button, a powerful short high-voltage pulse is supplied to the line, which can completely destroy or disrupt the functional activity of the information collection equipment.

Leakage protection devices through acoustic channels "Troyan"

Trojan Acoustic blocker of all information collection devices.

With the emergence of increasingly advanced devices for capturing and recording speech information, the use of which is difficult to detect with search technology (laser recording devices, stethoscopes, directional microphones, micro-power radio microphones with a remote microphone, wired microphones, modern digital voice recorders, radio bookmarks that transmit acoustic information over the electrical network and other communication and signaling lines at low frequencies, etc.), an acoustic masker often remains the only means that ensures guaranteed closure of all speech information leakage channels.

Principle of operation:

In the conversation area there is a device with external microphones (microphones must be at a distance of at least 40-50 cm from the device to avoid acoustic feedback). During a conversation, the speech signal is transmitted from the microphones to an electronic processing circuit, which eliminates the phenomenon of acoustic feedback (microphone - speaker) and turns the speech into a signal that contains the main spectral components of the original speech signal.

The device has an acoustic trigger circuit with an adjustable switching threshold. The acoustic release system (VAS) reduces the duration of exposure to speech interference on hearing, which helps reduce the effect of fatigue from exposure to the device. In addition, the battery life of the device increases. The speech-like interference of the device sounds synchronously with the masked speech and its volume depends on the volume of the conversation.

Small dimensions and universal power supply allow you to use the product in the office, car and any other unprepared place.

In the office, you can connect active computer speakers to the device to make noise in a large area, if necessary.

Main technical characteristics

Type of generated interference	speech-like, correlated with the original speech signal. The intensity of the interference and its spectral composition are close to the original speech signal. Each time the device is turned on, unique fragments of speech-like interference are presented
Range of reproduced acoustic frequencies	300 - 4000 Hz
Device management	using two external microphones
Audio amplifier output power
Maximum sound pressure from internal speaker
The voltage of the interference signal at the linear output depends on the position of the volume control and reaches the value
Product power	from a 7.4 V battery. The battery is charged from a 220 V power supply using the adapter that is included with the product.
Battery full charge time
Capacity of the battery used
The continuous operation time when powered by a fully charged battery depends on the sound volume and is	5 - 6 hours
Maximum current consumption at full volume
Product dimensions	145 x 85 x 25 mm

Equipment:

· Main unit,

· mains charging adapter,

· product passport with operating instructions,

Extension cord for computer speakers

· remote microphones.

Suppressor "Kanonir-K" for microphone listening devices

The product “CANNIR-K” is designed to protect the meeting place from means of collecting acoustic information.

Silent mode blocks radio microphones, wired microphones and most digital voice recorders, including voice recorders in mobile phones (smartphones). The product silently blocks the acoustic channels of mobile phones, which are located near the device on the emitter side. Blocking microphones of mobile phones does not depend on the standard of their operation: (GSM, 3G, 4G, CDMA, etc.) and does not affect the reception of incoming calls.

When blocking various means of picking up and recording speech information, the product uses both speech-like and silent ultrasonic interference.

In the speech-like interference mode, all available means of collecting and recording acoustic information are blocked.

A brief overview of voice recorder and radio microphone blockers available on the market:

· Microwave blockers: (storm), (noisetron), etc.

The advantage is the silent operation mode. Disadvantages: most modern digital voice recorders do not block the operation of voice recorders in mobile phones at all.

· Generators of speech-like signals: (fakir, shaman), etc.

They are effective only when the conversation volume level does not exceed the level of acoustic interference. Conversations have to be carried out in loud noise, which is tiring.

· Products (comfort and chaos).

The devices are very effective, but conversations have to be carried out in tight-fitting microtelephone headsets, which is not acceptable for everyone.

Main technical characteristics of the Kanonir-K product.

Power: rechargeable battery (15V. 1600mA.) (if the red LED goes out, you need to connect the charger). When the charger is connected, the green LED located near the “output” socket should light up. If the LED lights dimly or goes out, this indicates that the battery is fully charged. A bright LED indicates a low battery.

· Time to fully charge the battery - 8 hours.

· Current consumption in silent mode - 100 - 130 mA. In speech-like interference mode together with silent mode - 280 mA.

· The voltage of the speech-like noise signal at the linear output is 1V.

· Time of continuous operation in two modes simultaneously - 5 hours.

· The blocking range of radio microphones and voice recorders is 2 - 4 meters.

· Ultrasonic interference emission angle is 80 degrees.

· Dimensions of the product "CANNIR-K" - 170 x 85 x 35 mm.

The second chapter examined organizational measures for the protection of speech information, equipment for searching for technical reconnaissance means, and technical means for protecting acoustic information from leakage through technical channels. Since the use of technical means of protection is expensive, these means will not have to be used throughout the perimeter of the room, but only in the most vulnerable places. The equipment for searching technical means of reconnaissance and means of actively protecting information from leakage through vibroacoustic and acoustic channels were also examined. Since, in addition to technical channels for information leakage, there are other ways to steal information, these technical means must be used in conjunction with technical means of protecting information through other possible channels.

Chapter 3. Feasibility study

In this thesis project, the composition of material costs can be determined taking into account some features related to the installation of an acoustic and vibroacoustic protection system. IN in this case, since the work takes place on site, shop and general plant expenses must be combined under a single name of costs. As initial information for determining the amount of all costs of Sb.com, rubles, you can use formula 2.

Sb.com = M + OZP + DZP + Unified Social Tax + SO + OHR + KZ

where M is the cost of materials;

WFP - basic salary for specialists participating in the development of the program;

DZP - additional salary for specialists participating in the development of the program;

UST - unified social tax;

CO - costs associated with the operation of equipment (depreciation);

OCR - general economic costs;

KZ - non-production (commercial) expenses.

The calculation of financial costs is calculated taking into account the route maps presented in Table 9.

Operating time

During the installation process, equipment such as a puncher, crimping tool, and tester was used. The table shows the consumables and equipment needed to create a network

Vibroacoustic protection equipment (vibroacoustic noise generator “LGSh - 404” and emitters for it in the amount of 8 pieces) and the Canonir-K microphone listening device suppressor were purchased by the customer and are not taken into account in the calculation of material costs.

Cost sheet

Name of Materials	Unit	Price per unit of measurement, rub.	Quantity	Amount, rub.
3. Dowels
4. Self-tapping screws
5. Marker
6. Victory drill
8. Roulette
11. Phillips screwdriver

The volume of material costs for product M, rubles, is calculated using formula 3

М = Σ Рi · qi

where pi is the type of material i according to the quantity;

qi is the cost of specific unit i of material.

Calculation of the volume of material costs is calculated using the formula

M = 2+5+30+50+200+100=387 (rub.)

The calculation of the basic salary is carried out on the basis of the developed technological process of the work performed, which should include information:

about the sequence and content of all types of work performed,

on the qualifications of workers involved in performing certain types of work at all production stages (transitions, operations),

about the labor intensity of performing all types of work,

on the technical equipment of workplaces when performing work at all stages.

Since some preferential categories of employees and planned bonuses to the established tariffs for high-quality and timely completion of work may participate in the formation of the basic wage fund, correction factors are provided in the calculations. Their values ​​are determined on the basis of increasing interest rates relative to the direct costs of paying wages to employees. It is recommended to choose increasing interest rates in the range from 20% to 40%; in this work it is selected based on an interest rate of 30%, or Kzp = 0.3.

To determine financial costs, it is necessary to attract an employee with appropriate qualifications for whom the monthly salary must be determined. An employee’s salary for similar work is 50,000 rubles per month, based on this we will determine the hourly tariff rate Hours rubles/hour using the formula

Ochas = Zprmes/Tmonth

Zprmes - monthly salary;

The hourly tariff rate is calculated using formula 4

Calculation of the basic salary, RUB, is determined by the formula

OZP = Zprobsch + Zprobsch * Kzp

where Zprobsch is direct wages;

Кзп - increasing reference coefficient.

To determine the basic salary, first of all, you should calculate the direct salary Zpri, rubles, which is determined by formula 6

Zpri = OM * Tr/D * t

where OM - official salary (per month);

Tp - time spent on developing a program stage (hours);

D - number of working days per month; - duration of the working day (hour);

Zpri - direct wages at the i-th transition.

The basis of information for calculating direct wages is the route map.

After determining direct wages for transitions, the total amount of direct wages Zpr.totch, rubles is determined according to formula 7

Zpr.total =

Operational transitions of the work performed

Transition number according to route maps	The name of the operation	Operating time	Employee qualification (category)	Employee tariff rate
Transition 1	Preparatory
Transition 2	Blank
Transition 3	First editing room
Transition 4	Second editing room
Transition 5	Third editing room
Transition 6	Laying
Transition 7	Control
Transition 8	Connective
Transition 9	Tuning
Correction factor Kzp =0.3
Total: OZP taking into account the correction factor 4097.99

Let's determine the total salary based on all transactions

Zpr.total=284.0+284.0+615.3+284.0+568.0+426.0+123.0+284.0+284.0=3152.3 (rub)

Using the formula, we calculate the basic salary

OZP = 3152.3 + 3152.3*0.3 = 4097.99 (rub)

The calculation results are recorded in Table 11.

From Table 11 it can be seen that the OCP, taking into account the correction factor, amounted to 4097.99 rubles.

Additional wages are actual allowances to encourage the employee to complete his work on time, exceed the plan, and work with high quality.

Additional salary DZP, rubles, calculated by the formula

DZP = Kdzp * OZP

where Kdzp is the correction factor.

DZP taking into account the interest rate according to formula (8) we obtain

DZP = 4097.99 * 0.1 = 409.79 (rub.)

The unified social tax (contributions) includes monetary contributions to extra-budgetary funds: the Pension Fund of the Russian Federation, the Social Insurance Fund of the Russian Federation, the Compulsory Medical Insurance Fund. When calculating the amount of the single social tax to extra-budgetary funds in this work, an interest rate of 34% should be used. from the income of the population, then KESN = 0.34. In this case, the income of the population should include the total accruals of wages and salaries. The unified social tax is calculated using the formula

ESN = KESN * (OZP + DZP)

Unified Social Tax = 0.34 * (4097.99 + 409.79) = 1532.64 (rub.)

where KESN is the VAT correction factor.

OHR = KOHR * OZP

OHR = 4097.99 * 1.5 = 6146.98 (rub.)

It is recommended to calculate general business costs based on the recommended interest rate interval (120 ¸ 180)% of the basic salary (BW), using the given adjustment factor (KOHR), formula 10. The interest rate is selected 150%, KOHR = 1.5.

The costs of maintaining and operating equipment (depreciation) are determined by formula (11). To calculate depreciation charges, the following information is used:

cost of equipment;

moral aging period (depreciation period);

straight-line depreciation method.

The linear method was chosen because of the equipment used in device repair, since the obsolescence of this equipment occurs much faster than physical equipment, which requires its constant modernization or replacement with more advanced devices. Equipment operating hours in accordance with route maps. Equipment depreciation costs are presented in the table.

Depreciation on equipment

Name of device equipment	Depreciation period, years	Cost, rub.	Actual time worked, minutes		Actual costs for depreciation, rub.
1. Hammer
2. Tester

Actual costs for depreciation of CO, rubles, are determined by the formula

CO = (Equipment * Tf)/(Years * Months * Days * t)

where Oequipment is the cost of equipment (perforator 5000 rubles, tester 500 rubles);

Tf - actual time worked (perforator 60 minutes, tester 60 minutes);

Years - depreciation period (three years);

Months - number of months (12 months);

Days - number of working days per month (22 days); - duration of the working day (eight hours).

Let's determine the total actual costs for depreciation SOtot, rubles, using formula 12

COtotal = COtester + COperforator

SOtotal = 2.05 + 47.34 = 49.39 (rub.)

The total production cost is determined by the formula

Sbp.p = M + OZP + DZP + ESN + CO + OHR

Sbp.p = 387+4097.99+409.79+1532.64+49.39+6146.98=12623.79 (rub.)

KZ= Kk.z* Sbp.p

KZ = 12623.79 * 0.02 = 252.47 (rub.)

where Sbp.p is the total production cost.

The commercial cost of repair work on the Sb.com device, rubles, is determined by formula (15)

Sb.com = Sbp.p + KZ

Sb.com = 12623.79 + 252.47 = 12876.26 (rub.)

The commercial price Tscom, rubles, taking into account profitability, is determined by formula (16). Profitability for the industry is set at 25%, then Krent = 0.25.

Tscom = (Sb.com * Krent) + Sb.com

Tscom = (12876.26 * 0.25) + 12876.26 = 16095.32 (rub.)

where Krent is the profitability ratio.

Calculation of the price of an enterprise for organizing an acoustic and vibroacoustic protection system, taking into account profitability, is determined by formula (16)

The selling price, including VAT, is determined by formula (17). Value added tax, in accordance with the Law of the Russian Federation, is set at 18%, then KVAT = 0.18.

Tsotp = (Tskom * KNDS) + Tskom

Tsotp = (16095.32 * 0.18) + 16095.32 = 18992.47 (rub.)

where KVAT is the VAT coefficient.

Calculation of the price of an enterprise for organizing a video surveillance system, taking into account VAT, is determined by formula (3.16)

The total cost of the acoustic and vibroacoustic protection system was calculated, the cost of which was 18,992.47 rubles.

Conclusion. During the installation process, a complete check of the device was carried out using various testing devices and subsequent elimination of the faults found. The final stage of organizing an acoustic and vibroacoustic protection system is checking the quality of the work performed and the correct functioning of the device. It is possible to reduce the cost of a network only by purchasing cheaper equipment.

Chapter 4. Safety precautions and workplace organization

1 Explanation of requirements for premises and workplaces

1. The premises in which the equipment of acoustics and vibration acoustics systems are located must comply with safety requirements, fire safety, current building codes and regulations (SNiP), State standards, PUE (electrical installation rules), PTE (technical operation rules) of consumers and PTB (safety rules) for the operation of consumers, as well as the corresponding requirements of sanitary and hygienic standards.

2. With regard to the danger of electric shock to people, the following are distinguished:

a) Premises with increased danger, characterized by the presence of one of the following conditions creating an increased danger:

· Dampness (relative humidity exceeds 75% for a long time);

· High temperature (t°C exceeds +35°C for a long time);

· Conductive dust;

· Conductive floors (metal, earthen, reinforced concrete,

· brick, etc.);

· Possibility of simultaneous contact of workers and grounded metal structures of the building on the one hand and to the metal housings of electrical equipment on the other;

b) Particularly dangerous premises, characterized by the presence of one of the following conditions creating a particular danger:

· Particular dampness (relative air humidity is close to 100%), i.e. the floor, walls, ceiling and equipment are covered with moisture;

· Chemically active environment that destroys insulation and live parts of electrical equipment;

· The simultaneous presence of two or more conditions of increased absence of signs related to increased and special danger.

1.3. When performing work outdoors, the degree of danger of electric shock is determined by the senior person in charge of the work at the place where it is performed, depending on the specific conditions.

4. Bare live parts of equipment accessible to accidental human touch must be provided with reliable barriers in cases where the voltage on them exceeds:

a) In areas with increased danger - 42 V;

b) In particularly dangerous rooms - 12 V.

5. Whether the possibility of danger and the ways in which its impact on workers can be prevented or reduced must be indicated with signal colors and safety signs in accordance with GOST.

6. Each team at the workplace must have a first aid kit and first aid supplies, as well as individual and collective protective equipment.

Work in attics, building walls, basements.

Before starting work in the attic, the foreman or foreman, together with a representative of the housing maintenance organization, check the reliability of the attic floors, the serviceability of the stairs to enter the attic and the sanitary condition of the premises.

In the absence of safe working conditions, it is prohibited to start work.

Work in the attic, basement (high-risk premises) is carried out by a team of at least 3 people with an electrical safety group of at least II. Permission to work is issued by the owner of the building (housing office, department of economic protection, REU, etc.).

When working in the attic, care must be taken to avoid falling into open, unguarded hatches, or injury from nails sticking out in beams and boards. If there is no lighting in the attic or basement, work must be done using the light of a portable electric lamp, voltage up to 42V, or a flashlight.

The use of open fire (candles, matches, etc.) and smoking is prohibited.

The team allowed to work in the attic must have the following personal protective equipment:

a) voltage indicator (TIN-1);

c) dielectric gloves, galoshes, boots;

d) safety glasses, helmet;

e) rechargeable (battery) flashlight;

f) first aid kit. help.

Laying cables in attics, basements and building walls

All cable inputs and outputs to the attic and basement must be protected with a metal sleeve from accidental mechanical damage, and also securely fastened to walls, wooden beams, etc.

Lay the cable in attics and basements so that it does not interfere with the passage through those. floor, performing any work by other operational services (telephone operators, antenna operators, mechanics, plumbers, electricians, radio technicians, etc.).

A) In high attics (gable sloping roof), the main cable is laid at a height of no less than 2 m 30 cm from the floor and is secured to the load-bearing support beams with a cable or metal strip (staples) preventing the cable from sagging.

b) Cable laying along the walls from the entrance to the attic, to the basement to the equipment installation site should be done with overhead brackets (metal/strip, etc.) with a distance of at least 350 mm from each other. When laying the cable parallel to the electric On the reins, the distance between them must be at least 250 mm. At intersections with electrical wires (cable), the television cable must be enclosed in an insulating tube. If it is necessary to lay the cable parallel to radio broadcasting and telephone (low-current) lines, the distance between them is at least 100 mm.

Also, the cable should be laid at least 1 m away from hot water supply pipes, heating pipes and ventilation ducts.

Installation of equipment inside buildings

Before starting work, the foreman or workman must determine the installation location of the equipment and its connection to the power supply network, and its grounding.

The equipment must be located in special metal cabinets with mandatory grounding or on mounting panels that also have a grounding element (bolt, washer, nut, etc.) in places with free and convenient access for installation and maintenance of the equipment. Also desirable are the factors of sufficient lighting and free space necessary to carry out the work.

The equipment should be located away from television, telephone, public service networks, etc. equipment at a distance of at least 2 meters to avoid induced interference.

In connection with the requirements of Mosproekt, power supplies should be located in electrical panels of buildings with mandatory grounding; hermetic power breakers are installed on mounting panels installed in basements, attics, etc., intended for fastening equipment, because basements, attics And. d. belong to the category of high-risk premises, and in case of accidents (break of water supply, sewerage, hot water supply, etc.) to the category of dangerous premises b) tools with insulating handles;

Equipment should be placed on mounting panels based on ease of installation and operation, as well as aesthetics. There should be convenient access to the mounting and adjustment components of the equipment.

The cables on the mounting panel must be secured so that:

a) Did not interfere with free access to the equipment;

b) They had an additional length reserve of no more than 1-2 additional cable cuts.

c) Must be marked: cable purpose, input, output.

Cables suitable (supplied) to the mounting panel or metal cabinet must also be secured to walls, beams, etc. and are protected by a metal sleeve, boxes, plastic or metal tubes, and must not interfere with the passage, approach and work near the mounting panel.

It is imperative to avoid crossing the input and output of the amplification equipment.

Trunk equipment of adjacent parallel lines (amplifiers, tie-in units, IGZ, power passes, adders, etc.)

It is prohibited to install the equipment:

a) In boiler rooms, on the roofs of buildings.

b) Near pipes: sewer, hot and cold water supply, gas, as well as on air ducts and ventilation ducts, etc.

c) Throughout the entire route, the cable must be laid in a straight line, without sagging and tightly adjacent to the wall.

d) In low attics and basements, the cable is laid either along the walls with the requirements specified above, or on a cable with mandatory reliable fastening of the cable to the strong structures of the attic, basement, and with mandatory cable tension.

e) When bending and turning the cable, observe the permissible bending radius of the cable (technical conditions for cable products).

e) When the cable is laid openly at a height of less than 2.3 m from the floor level or 2.8 m from the ground level, it must be protected from mechanical damage (metallic hose, metallic pipes, etc.)

g) Electrical wires (220V, 22V) must be protected with a metal sleeve (metal or plastic tubes), if electrical. the cable is mounted at a height of less than 2.3 m from the floor or 2.8 m from the ground along the entire length of its route along the attic or facade of the building, and if higher than 2.3 m from the floor and 2.8 m from the ground, then use Protecting pieces of metal hose up to 3 meters long from the installation site of equipment and cable entry into the attic or basement should be installed at a distance of at least 50 cm from each other.

Work in attics and basements at air temperatures above 50°C (indoors) is prohibited.

Cable laying in basements on trays (racks) must be carried out with mandatory cable fastening with a distance between fastenings of 1 m.

When pulling a cable through a low-current riser (between floors), the cable must be secured (with brackets, plastic ties, wire, etc.) on each odd-numbered floor with the obligatory laying out of the cable inside the low-current cabinet.

It is prohibited to pull the cable through the mortgages where the power cable distribution is located.

If it is not possible to lay cables along low-current risers (the embedded pipe or channel is overfilled or broken), a low-current riser must be laid with the obligatory permission and indication of the installation location and mandatory grounding of the riser by the owner of the building.

Conclusion

Upon completion of the work, the following conclusions can be drawn. Voice information in a protected area is of the greatest value, so it is necessary to pay close attention to its protection.

The main threats to information security during a meeting are: eavesdropping and unauthorized recording of speech information using embedded devices, laser eavesdropping systems, voice recorders, interception of electromagnetic radiation arising from the operation of sound recording devices and electrical appliances.

As the main organizational measures, it is recommended to check the premises before the meeting in order to assess the state of information security, control the access of meeting participants to the premises, and organize monitoring of the entrance to the allocated premises and the surrounding environment.

The main means of ensuring the protection of acoustic information during a meeting is the installation of various noise generators, blocking of embedded devices in the room, and sound insulation. The main technical means of protecting information were the installation of double doors, sealing the cracks in the windows with sound-absorbing material, and the installation of technical means of protecting information in the room.

The main goal of the attacker is to obtain information about the composition, condition and activities of an object of confidential interests (company, product, project, recipe, technology, etc.) in order to satisfy his information needs. It is possible, for selfish purposes, to make certain changes to the composition of information circulating at an object of confidential interests. Such an action can lead to misinformation regarding certain areas of activity, accounting data, and the results of solving certain problems. A more dangerous goal is the destruction of accumulated information arrays in documentary or magnetic form and software products. The full amount of information about a competitor’s activities cannot be obtained only by one of the possible methods of accessing information. The more information capabilities an attacker has, the more success he can achieve in competition.

In the same way, methods for protecting information resources should represent a holistic set of protective measures

Bibliography

1. GOST R 50840-95. Methods for assessing quality, legibility and recognition.

A collection of temporary methods for assessing the security of confidential information from leakage through technical channels. State Commission of Russia. - M.: 2002

Khorev A.A. Protection of information from leakage through technical channels. Part 1. Technical channels of information leakage. Tutorial. - M.: State Technical Commission of Russia. 1998, 320 p.

5. Torokin A.A. Engineering and technical information security. Tutorial. - M.: RF Ministry of Defense, 2004, 962 p.

6. Khorev A.A., Makarov Yu.K. To assess the effectiveness of acoustic (speech) information protection // Special technology. - M.: 2000. - No. 5 - P. 46-56.

7. “Information Protection”, “Confident”, “Security Systems, Communications and Telecommunications”: Magazines. - M.: 1996. - 2000. P. “Novo”, “Grotek”, “Information Protection”, “Mask”; Catalogs of companies. - M., 2003. - 2007.

8. Yarochkin V.I. Information Security. - M.: Mir, - 2005, 640 p.

Information Security. Encyclopedia XXI century. - M.: Weapons and technologies, - 2003, 774 p.

State standard of the Russian Federation GOST R 50922-2006. Data protection. Basic terms and definitions. Approved and put into effect by order of the Federal Agency for Technical Regulation and Metrology dated December 27, 2006 N 373-st.

State standard of the Russian Federation GOST R 52069.0-2003 “Information protection. System of standards. Basic provisions". Adopted by Resolution of the State Standard of the Russian Federation dated June 5, 2003 N 181-st

State standard of the Russian Federation GOST R 52448-2005 “Information protection. Ensuring the security of telecommunication networks. General provisions". Adopted by Resolution of the State Standard of the Russian Federation dated January 1, 2007 N 247

Interstate standard GOST 29099-91 “Local computer networks. Terms and Definitions". Adopted by Resolution of the State Standard of the Russian Federation dated January 1, 1993 N 1491

Anansky E.V. Information protection is the basis of business security // Security Service. 2005. No. 9-10. - P.18-20.

Wim van Eyck. Electromagnetic radiation from video display modules: the risk of information interception // Information protection. Confidential. 2007. No. 1, No. 2.

Bezrukov V.A., Ivanov V.P., Kalashnikov V.S., Lebedev M.N. Radio masking device. Patent No. 2170493, Russia. Published date 2007. 07. 10.

Lebedev M.N., Ivanov V.P. Generators with chaotic dynamics // Instruments and experimental techniques. Moscow, Nauka, 2006, No. 2, pp. 94-99.

Kalyanov E.V., Ivanov V.P., Lebedev M.N. Forced and mutual synchronization of generators in the presence of external noise // Radio engineering and electronics. Moscow, 2005, volume 35, issue. 8. P.1682-1687

Ivanov V.P., Lebedev M.N., Volkov A.I. Radio masking device. Patent No. 38257, Russia. Published date 2007. 27.

Chekhovsky S.A. The concept of building computers protected from information leakage through electromagnetic radiation channels. International scientific and practical conference "Information Security in Information and Telecommunication Systems". Abstracts of reports. Publishing house "Interlink", Moscow 2006, p.80.

Kozhenevsky S.R., Soldatenko G.T. Preventing information leakage through technical channels in personal computers. Scientific and technical journal "Defender of Information" 2006, No. 2, pp. 32-37.

Ovsyannikov V.V., Soldatenko G.T. Do we need secure computers? Scientific and methodological publication "Special Purpose Equipment", 2005, No. 1, pp. 9-11.

23.

Annotation: The lecture discusses methods and means of protecting acoustic (speech) information: sound insulation, noise reduction, suppression of voice recorders. The basic requirements and recommendations of STR-K for the protection of speech information are given.

Methods for protecting acoustic (speech) information are divided into passive and active. Passive methods are aimed at weakening direct acoustic signals circulating in the room, as well as the products of electroacoustic transformations in HTSS and OTSS and connecting circuits. Active methods involve the creation of masking interference and the suppression/destruction of technical means of acoustic reconnaissance.

Soundproofing

The main passive method of protecting acoustic (speech) information is sound insulation. Isolation of an acoustic signal by an attacker is possible if the signal-to-noise ratio is within a certain range. The main purpose of using passive information security tools- reduction of the signal-to-noise ratio at possible points of information interception due to a decrease in the informative signal. Thus, sound insulation localizes radiation sources in a confined space in order to reduce the signal-to-noise ratio to a limit that eliminates or significantly complicates the collection of acoustic information. Let's consider a simplified sound insulation scheme from a physics point of view.

When falling acoustic wave Most of the incident wave is reflected onto the boundary of surfaces with different specific planes. The reflectivity of a surface depends on the density of the material from which it is made and the speed at which sound travels through it. Reflection acoustic wave can be imagined as the result of a collision of air molecules m with molecules of a reflective surface M. Moreover, if M>>m, then the speed of the massive ball is close to zero after the impact. In this case, almost all the kinetic energy acoustic wave turns into potential energy of elastic deformation of motionless balls. When the shape is restored, the deformed balls (surfaces) impart a speed to the air molecules hitting them that is close to the original, but in the opposite direction - this is how a reflected wave appears.

Smaller part acoustic wave penetrates the soundproofing material and spreads through it, losing its energy.

For solid, homogeneous building structures, the attenuation of acoustic signals, which characterizes the quality of sound insulation, is calculated as follows (for medium frequencies):

Weight of the fence, kg;

Sound frequency, Hz.

At the design stage of dedicated premises, when choosing enclosing structures, you must adhere to the following:

• use acoustically inhomogeneous structures as flooring;
• as a floor, use structures installed on vibration isolators or structures on an elastic foundation;
• better use dropped ceilings with high sound absorption;
• as walls and partitions, it is preferable to use multilayer acoustically inhomogeneous structures with gaskets made of materials such as rubber, cork, fiberboard, MVP, etc.

In any room, the most vulnerable from the point of view of acoustic intelligence are doors and windows.

Window glass vibrates violently under pressure acoustic wave, therefore it is advisable to separate them from the frames with rubber gaskets. For the same reason, it is better to use triple or at least double glazing on two frames fixed in separate boxes. At the same time, install closely spaced glasses on the outer frame, and sound-absorbing material between the frames.

Doors have significantly lower surface densities than other enclosing structures and have gaps and cracks that are difficult to seal. Thus, standard door very poorly protected, so doors with increased sound insulation should be used. For example, the use of sealing gaskets increases the sound insulation of doors by 5-10 dB. Better to install double doors with a vestibule and vibration isolation from each other. Characteristics of sound absorption properties various designs are given in tables 14.1, 14.2.

Table 14.1.

Type	Design
		125	250	500	1000	2000	4000
Panel door lined with plywood on both sides	without gasket	21	23	24	24	24	23
		27	27	32	35	34	35
Typical door P-327	without gasket	13	23	31	33	34	36
	with foam rubber gasket	29	30	31	33	34	41

Table 14.2.

Type	Sound insulation (dB) at frequencies Hz
	125	250	500	1000	2000	4000
Single glazing
thickness 3 mm	17	17	22	28	31	32
thickness 4 mm	18	23	26	31	32	32
thickness 6 mm	22	22	26	30	27	25
Double glazing with air gap
57mm (thickness 3mm)	15	20	32	41	49	46
90 mm (thickness 3 mm)	21	29	38	44	50	48
57mm (thickness 4mm)	21	31	38	46	49	35
90 mm (thickness 4 mm)	25	33	41	47	48	36

The use of sound-absorbing materials has some features associated with the need to create an optimal ratio of direct and reflected acoustic signals from the obstacle. Excessive sound absorption reduces signal strength. The value of sound attenuation by various barriers is given in Table 14.3.

Table 14.3.

Fencing type	Sound insulation (dB) at frequencies Hz
	125	250	500	1000	2000	4000
Brick wall	0,024	0,025	0,032	0,041	0,049	0,07
Wood upholstery	0,1	0,11	0,11	0,08	0,082	0,11
Single glass	0,03	-	0,027	-	0,02	-
Lime plaster	0,025	0,04	0,06	0,085	0,043	0,058
Felt (thickness 25mm)	0,18	0,36	0,71	0,8	0,82	0,85
Pile carpet	0,09	0,08	0,21	0,27	0,27	0,37
Glass wool (thickness 9 mm)	0,32	0,4	0,51	0,6	0,65	0,6
Cotton fabric	0,03	0,04	0,11	0,17	0,24	0,35

Sound-absorbing materials - materials used for interior decoration premises in order to improve their acoustic properties. Sound-absorbing materials can be simple or porous. IN simple materials sound is absorbed as a result of viscous friction in the pores (foam concrete, gas glass, etc.). In porous materials, in addition to friction in the pores, relaxation losses occur due to the deformation of the non-rigid skeleton (mineral, basalt, cotton wool). Typically the two types of material are used in combination with each other. One of the common types of porous materials is cladding sound-absorbing materials. They are made in the form flat slabs(“Akmigran”, “Akminit”, “Silakpor”, “Vibrostek-M”) or relief structures (pyramids, wedges, etc.), located either closely or at a short distance from a solid building structure (walls, partitions, fences, etc.). Figure 14.4 shows an example of a sound-absorbing slab. For the production of slabs such as "Akmigran", mineral or glass is used. granular cotton wool and binders consisting of starch, carboxylcellulose and bentonite. From the prepared mixture, slabs 2 cm thick are formed, which, after drying, are subjected to finishing (calibrated, sanded and painted). The front surface of the slabs has a cracked texture. The density of sound-absorbing material is 350-400 kg/m3. Attaching sound-absorbing slabs to the ceiling is usually done using metal profiles.

Rice. 14.1.

Porous sound-absorbing materials are ineffective at low frequencies. A separate group of sound-absorbing materials consists of resonant absorbers. They are divided into membrane and resonator. Membrane absorbers are a stretched canvas (fabric), a thin plywood (cardboard) sheet, under which a well-damping material is placed (material with high viscosity, for example, foam rubber, sponge rubber, construction felt, etc.). In absorbers of this type, maximum absorption is achieved at resonant frequencies. Perforated resonator absorbers are a system of air resonators (for example, Helmholtz resonators), at the mouth of which damping material is located.

The signal level behind the obstacle is estimated using the following formula:

Let's look at an example of soundproofing a fence and floor.

When it comes to constructing a partition with high sound-proofing properties, it is proposed to consider a partition on two independent frames covered with two layers of gypsum fiber sheets on each side as an effective design. In this case, a system is used consisting of two independent metal frames with a thickness of 50, 75 or 100 mm, which are sheathed on both sides with gypsum fiber board sheets in two layers, each 12.5 mm thick. When installing this structure, all elements of metal frames, as well as the ends GVL sheets, are adjacent to all other structures, including load-bearing ones, through a layer of vibration-proofing material 6 mm thick. Metal frames are mounted parallel to each other with a gap of at least 10 mm to eliminate possible connections with each other. The internal space of the partition is filled with sound-absorbing basalt slabs to a thickness equal to at least 75% of the total internal thickness partitions. The airborne noise insulation index of a partition on two frames of 100 mm each with a total thickness of 260 mm is equal to Rw = 58 dB, a partition based on profiles 50 mm thick each provides a sound insulation value equal to Rw = 54 dB with a thickness of 160 mm

Existing wall.

Plates made of glass staple fiber (2 layers of 20 mm each).

Polyethylene film.

Screed 80mm.

Mesh reinforcement.

Laying around the perimeter of the room from glass-staple slabs (1 layer).

2 layers of soundproofing material, for example, glass staple fiber, are laid on the floor slab. In this case, all the walls of this room are covered with a single layer of material 20 mm thick and a height slightly greater than the height of the screed being installed. A separating layer of polyethylene film is laid on top of the material, on which a concrete leveling screed 80 mm thick, reinforced metal mesh to give it increased mechanical strength.

To increase sound insulation in rooms, acoustic screens can be installed along the path of sound propagation in the most dangerous directions from the point of view of leakage. As a rule, screens are used to protect temporary premises.

For conducting confidential conversations, so-called soundproof booths have also been developed, which are divided into frame and frameless. The first ones have metal carcass, on which they are attached sound absorbing panels. Cabins with two-layer sound-absorbing plates provide sound attenuation up to 35... 40 dB. Frameless cabins are more efficient. They are assembled from ready-made multilayer panels connected using soundproofing elastic gaskets. The efficiency of such cabins lies in the range of 50...55 dB.

Attenuation of acoustic (speech) signals at the border of the controlled zone to values ​​that ensure the impossibility of their identification by reconnaissance means against the background of natural noise;

Attenuation of information electrical signals in VTSS connecting lines containing electroacoustic transducers (having a microphone effect) to values ​​that ensure the impossibility of their identification by reconnaissance means against the background of natural noise;

Elimination (weakening) of the passage of HF interference signals to auxiliary technical means containing electroacoustic transducers (having a microphone effect);

Detection of emissions from acoustic bookmarks and side electromagnetic emissions from voice recorders in recording mode;

Detection of unauthorized connections to telephone lines.

Active methods protections are aimed at:

Creation of masking acoustic and vibration interference in order to reduce the signal-to-noise ratio at the border of the controlled area to values ​​that ensure the impossibility of isolating an informational acoustic signal by reconnaissance means;

Creation of masking electromagnetic interference in VTSS connecting lines containing electroacoustic transducers (having a microphone effect), in order to reduce the signal-to-noise ratio to values ​​that ensure the impossibility of isolating an information signal by reconnaissance means;

Electromagnetic suppression of voice recorders in recording mode;

Ultrasonic suppression of voice recorders in recording mode;

creation of masking electromagnetic interference in power supply lines of high-voltage communication systems, which have a microphone effect, in order to reduce the signal-to-noise ratio to values ​​that make it impossible to isolate an informational acoustic signal by reconnaissance means;

Creation of targeted radio interference to acoustic and telephone radio signals in order to reduce the signal-to-noise ratio to values ​​that ensure the impossibility of isolating an informational acoustic signal by reconnaissance means;

Suppression (disruption of functioning) of means of unauthorized connection to telephone lines;

Destruction (disablement) of means of unauthorized connection to telephone lines.

Attenuation of acoustic (speech) signals is carried out by sound insulation. The attenuation of informative electrical signals in HTSS lines and the exclusion (attenuation) of the passage of HF interference signals is carried out by the method of signal filtering.

At the core active methods protection of acoustic information lies in the use various types field generators, as well as the use of special technical means.

3.1. Soundproofing of premises

Soundproofing of premises is aimed at localizing the sources of acoustic signals inside them and is carried out in order to exclude the interception of acoustic (speech) information via direct acoustic (through cracks, windows, doors, ventilation ducts, etc.) and vibration (through enclosing structures, water pipes). , heat, gas supply, sewerage, etc.) channels.

Sound insulation is assessed by the amount of attenuation of the acoustic signal, which for solid single-layer or homogeneous fences at medium frequencies is approximately calculated by the formula /5/:

K og = , dB,

Where q p– weight of 1 m 2 fencing, kg;

f– sound frequency, Hz.

Sound insulation of premises is ensured with the help of architectural and engineering solutions, as well as the use of special construction and finishing materials.

One of the weakest soundproofing elements enclosing the structures of designated premises are windows and doors. An increase in the soundproofing ability of doors is achieved by tightly fitting the door leaf to the frame, eliminating gaps between the door and the floor, using sealing gaskets, upholstering or lining the door leaves with special materials, etc. If the use of door upholstery is not enough to ensure sound insulation, then double doors are installed in the room , forming a vestibule. The internal surfaces of the vestibule are also lined with absorbent coatings.

The soundproofing ability of windows, like doors, depends on the surface density of the glass and the degree of pressing of the rebates. The sound insulation of single glazed windows is comparable to the sound insulation of single doors and is not sufficient for reliable protection information in the room. To ensure the required degree of sound insulation, double or triple glazing is used. In cases where it is necessary to provide increased sound insulation, windows are used special design(for example, a double window with filling the window opening organic glass thickness 20...40 mm). Window designs with increased sound absorption have been developed based on double-glazed windows with sealing of the air gap between the glasses and filling it with various gas mixtures or creating a vacuum in it.

To increase the sound insulation of a room, acoustic screens are used, installed along the path of sound propagation in the most dangerous (from an intelligence point of view) directions. The actions of acoustic screens are based on the reflection of sound waves and the formation of sound shadows behind the screen.

Sound-absorbing materials can be solid or porous. Typically, porous materials are used in combination with solid ones. One of the common types of porous materials is sound-absorbing facing material.

Porous sound-absorbing materials are ineffective at low frequencies. Individual sound-absorbing materials constitute resonant absorbers. They are divided into membrane and resonator.

Membrane absorbers are a stretched canvas (fabric) or a thin plywood (cardboard) sheet, under which a well-damping material is placed (material with high viscosity, for example, foam rubber, sponge rubber, construction felt, etc.). In absorbers of this type, maximum absorption is achieved at resonant frequencies.

Perforated resonator absorbers are a system of air resonators (Helmholtz resonator), at the mouth of which damping material is located. Increasing the sound insulation of walls and partitions of premises is achieved by using single-layer and multi-layer (usually double) fences. In multilayer fencing, it is advisable to select layer materials with sharply different acoustic resistances (concrete - foam rubber). The level of the acoustic signal behind the fence can be approximately estimated using the formula /5/:

Where Rc– level of the speech signal in the room (in front of the fence), dB;

S og– fence area, dB;

K og– sound insulation of the fence, dB.

There are many technological communications between rooms, buildings and structures (heat, gas, water supply, cable power supply networks). For them, appropriate holes and openings are made in the walls and ceilings. Their reliable sound insulation is ensured by the use of special sleeves, boxes, gaskets, mufflers, viscoelastic fillers, etc. Providing the required sound insulation of ventilation ducts is achieved by using complex acoustic filters and mufflers. It should be borne in mind that in the general case of sound insulation of enclosing structures containing several elements, the sound insulation of the weakest of them should be assessed.

Special soundproof booths have been designed for confidential conversations. Structurally, they are divided into frame and frameless. In the first case, sound-absorbing panels are attached to a metal frame. Cabins with two-layer sound-absorbing slabs provide sound attenuation up to 35...40 dB.

Frameless type cabins have higher acoustic efficiency (higher attenuation coefficient). They are assembled from ready-made multilayer panels connected to each other through soundproofing elastic gaskets. Such cabins are expensive to manufacture, but the sound level reduction in them can reach 50 ... 55 dB.

Related information.

Methods and means of protecting against leakage of confidential information through technical channels

Protection of information from leakage through technical channels is a set of organizational, organizational, technical and technical measures that exclude or weaken the uncontrolled release of confidential information outside the controlled area.

Protection of information from leakage via visual-optical channels

In order to protect information from leakage via the visual-optical channel, it is recommended:

· position the protected objects so as to prevent the reflection of light towards the possible location of the attacker (spatial reflections);

· reduce the reflective properties of the protected object;

· reduce the illumination of the protected object (energy restrictions);

· use means of blocking or significantly weakening reflected light: screens, screens, curtains, shutters, dark glasses and other obstructing environments, obstacles;

· use means of masking, imitation and others in order to protect and mislead the attacker;

· use means of passive and active protection of the source from the uncontrolled spread of reflected or emitted light and other radiation;

· camouflage protected objects by varying the reflective properties and background contrast;

· camouflage means for hiding objects can be used in the form of aerosol curtains and camouflage nets, paints, and shelters.

Protection of information from leakage via acoustic channels

The main measures in this type of protection are organizational and organizational-technical measures.

Organizational measures involve the implementation of architectural, planning, spatial and regime measures. Architectural and planning measures provide for the imposition of certain requirements at the design stage of buildings and premises or their reconstruction and adaptation in order to eliminate or mitigate the uncontrolled propagation of sound fields directly in the airspace or in building structures in the form of 1/10 structural sound.

Spatial the requirements may include both the choice of the location of premises in spatial terms and their equipment with elements necessary for acoustic security, excluding direct or reflected sound propagation towards the possible location of an intruder. For these purposes, the doors are equipped with vestibules, the windows are oriented towards the territory protected (controlled) from the presence of unauthorized persons, etc.

Regime measures provide for strict control of the presence of employees and visitors in the controlled area.

Organizational and technical measures suggest passive(sound insulation, sound absorption) and active(sound suppression) activities.

The use of technical measures through the use of special protected means of conducting confidential negotiations (protected speaker systems).

To determine the effectiveness of protection when using sound insulation, sound level meters are used - measuring instruments, converting sound pressure fluctuations into readings corresponding to the sound pressure level.

In cases where passive measures do not provide the required level of security, active means are used. Active means include noise generators - technical devices that produce noise-like electronic signals. These signals are supplied to the corresponding acoustic or vibration transformation sensors. Acoustic sensors are designed to create acoustic noise indoors or outdoors, and vibration ones are designed to mask noise in enclosing structures.