At this stage, the concept of the future facility is being developed, the main technical and economic characteristics are determined. The sketch determines the landing of the object on the ground, its volumetric-spatial solution, and the structural scheme. Also at this stage, the main engineering loads for water, heat and electricity are calculated, the so-called. calculation of loads.

Development of PP stages

Stage 2 - PD. Project documentation

4.2. Working documentation
4.2.1. The composition of the working documentation handed over to the customer includes:
- working drawings intended for the production of construction and installation work;
- attached documents, developed in addition to the working drawings of the main set.
4.2.2. The main sets of working drawings include general data on working drawings, drawings and diagrams provided for by the relevant standards of the System of Design Documentation for Construction (hereinafter - SPDS).
...
4.2.6. The attached documents include:
- working documentation for construction products;
- sketch drawings of general types of non-standard products, performed in accordance with GOST 21.114;
- specification of equipment, products and materials, carried out in accordance with GOST 21.110;
- questionnaires and dimensional drawings carried out in accordance with the data of the equipment manufacturers;
- local estimates by forms;
- other documents stipulated by the relevant SPDS standards.
The specific composition of the attached documents and the need for their implementation are established by the relevant SPDS standards and design assignment.
...
4.2.8. In working drawings, it is allowed to use standard building structures, products and assemblies by referring to documents containing working drawings of these structures and products. Reference documents include:
- drawings of typical structures, products and assemblies;
- standards, which include drawings intended for the manufacture of products.
Reference documents are not included in the composition of the working documentation handed over to the customer. The design organization, if necessary, transfers them to the customer under a separate agreement.

Construction works associated with the construction of buildings are divided into general construction and special types.

General construction works We are actions aimed at the construction of the building itself, including finishing work.

Special work, this is the installation of utilities and other actions aimed at ensuring the functionality of buildings such as: ventilation, water supply, sewerage, gas supply, electric lighting, installation of telephones and improvement of the adjacent territory.

Each such set of documents is assigned a name and a characteristic brand, which is applied on the drawing in the title block. The stamp is made up of the initial caps of the title of the original part of the project.

Note:

If necessary, additional marks of working drawings can be assigned. At the same time, no more than three capital letters of the Russian alphabet are used for stamps, usually selected from the initial letters of the names of a set of drawings

А ... - the ellipsis is replaced by the mark of the selected set of working drawings.

The mark applied to the drawing consists of an alphabetic abbreviation indicating which set of working drawings of the project this document belongs to and numbers indicating its serial number.

AC4 - Architectural and construction solution with serial number 4

KZh12 - Reinforced concrete structures with serial number 12

Drawings, according to which building structures are manufactured in factories, are called blank drawings.

In the process of erecting buildings and structures, they often make some changes in the layout of premises or completely replace some structures with others. In such cases, the corresponding changes are made to these drawings or the drawings are redone again.

Drawings that fully reflect the layout of the premises of the building being erected, its dimensions and characteristic structures are called executive.

Building drawings, developed on the basis of measurements, are called measurements.

Project of TM and ATM of the production and administrative buildings of the enterprise. The ATM section is common for 2 buildings.

Composition and examples of drawings of sections TM and ATM

Project of TM of the production building:

common data

For hot water preparation, a Buderus logalux ST 200 water heater tank with a capacity of 200 liters is provided.

The circulation in the heating system is forced by means of WILO-Top-S pumps.

The thermal expansion of the water is compensated for by a 100 liter Reflex N100 diaphragm expander.

The boiler equipment is operated by the boiler house operator.
Storage of firewood is carried out in a specially designated place on the territory of the organization under a canopy.

TM project of the administrative building:

common data
Process flow diagram of boiler room pipelines
Fragment of the layout plan for boiler room equipment M 1:50. Section 1-1.2-2.

The boiler room is equipped with a solid fuel (wood) VITOLIG 150 (VIESSMANN) gas generating boiler with a thermal power of 40 kW.
The circulation in the heating system is forced by means of WILO-Star-RS pumps.
The heating circuit is replenished via an automatic valve (VF 06).
The thermal expansion of the water is compensated by the Reflex membrane expander
N50 with a capacity of 50 liters.

ATM project of the administrative building:

common data
Automation scheme.
The schematic diagram of the electrical control of circulation pumps.
Return pressure alarm.
Schematic electrical diagram and connections of external wiring.
Circulation pumps. External wiring connection diagram.
Fragment of the plan for OTM. 000

The ATM section provides for the automation of the operation of circulation pumps, depending on the decrease or increase in pressure in the network. When the pressure in the network decreases, one of the pumps turns on, and when the pressure rises, it turns off. Pumps are mutually redundant. There is a choice of reserve when one of the pumps is inoperative.

Light and sound signaling of the operation of the circuit is provided in the form of a signal post PS-1U2, which is installed locally in the boiler room. Pressure control in the return pipeline is provided by the installation of an electrical contact pressure gauge with the removal of a light and sound signal to the AS-13 light signaling device.

It is customary to develop design documentation for construction in several stages, which differ in the composition and depth of elaboration of design solutions. The main requirements for the execution of documentation for various stages are set out in GOST R 21.1101-2009.

Let's consider all stages of the project in order:

• Stage 2 - PD. Design documentation

Stage 1 - PP. Pre-design studies (Draft design)

At this stage, the concept of the future facility is being developed, the main technical and economic characteristics are determined. The sketch determines the landing of the object on the ground, its volumetric-spatial solution, and the structural scheme. Also at this stage, the main engineering loads for water, heat and electricity are calculated, the so-called. calculation of loads.

Development of PP stages optional, but helps save time and money in future design.

Stage 2 - PD. Project documentation

In contrast to the Draft Design Stage "Project"("PD" or simply "P") is mandatory and subject to approval by the state executive authorities. Based on the results of the approval of the “Project” Stage, a permit for the construction of the facility is issued. The composition and content of this stage is regulated by the Decree of the Government of the Russian Federation No. 87 dated 16.02.2008. Of course, the composition will be individual for each project, but we will try to compile the most complete list of all possible sections and subsections of the "PD" Stage:

Stage 3 - RD. Working documentation

Stage "RD" it is necessary primarily for builders, since it most fully and in detail develops design solutions, which were only indicated in the "PD" Stage. Unlike "P", "Work" includes drawings of nodes, axonometric diagrams and profiles of engineering networks, specifications, etc. On the other hand, at the working stage, the documentation loses some sections, the completeness of which was exhausted at the design stage (for example , POS, OOS, KEO, ITM GOiChS, etc.). As in Stage "P", the composition of "RD" will be individual for each project, but we will try to compile the most complete list of all possible sections of the Stage "Working documentation":

GOST R 21.1101-2009 Design documentation system:

4.2. Working documentation
4.2.1. The composition of the working documentation handed over to the customer includes:
- working drawings intended for the production of construction and installation work;
- attached documents, developed in addition to the working drawings of the main set.
4.2.2. The main sets of working drawings include general data on working drawings, drawings and diagrams provided for by the relevant standards of the System of Design Documentation for Construction (hereinafter - SPDS).
...
4.2.6. The attached documents include:
- working documentation for construction products;
- sketch drawings of general types of non-standard products, performed in accordance with GOST 21.114;
- specification of equipment, products and materials, carried out in accordance with GOST 21.110;
- questionnaires and dimensional drawings carried out in accordance with the data of the equipment manufacturers;
- local estimates by forms;
- other documents stipulated by the relevant SPDS standards.
The specific composition of the attached documents and the need for their implementation are established by the relevant SPDS standards and design assignment.
...
4.2.8. In working drawings, it is allowed to use standard building structures, products and assemblies by referring to documents containing working drawings of these structures and products. Reference documents include:
- drawings of typical structures, products and assemblies;
- standards, which include drawings intended for the manufacture of products.
Reference documents are not included in the composition of the working documentation handed over to the customer. The design organization, if necessary, transfers them to the customer under a separate agreement.

SNiP 11-01-95 Composition of working documentation:

5.1. The composition of the working documentation for the construction of enterprises, buildings and structures is determined by the relevant state standards of the SPDS and is specified by the customer and the designer in the design agreement (contract).

5.2. State, industry and republican standards, as well as drawings of standard structures, products and assemblies, which are referenced in the working drawings, are not included in the working documentation and can be transferred by the designer to the customer, if it is stipulated in the contract.

The main goal of the center is to help in construction, both developers and buyers of real estate.

The main areas of activity are:

1. Preparation of design documentation for construction
2. Examination of design documentation to obtain a building permit.
3. Geological and geodetic surveys
4. Obtaining technical specifications for construction
5. Construction, technical and forensic examination
6. Industrial safety expertise
7. Construction and installation work of any complexity

By contacting us, any client receives a free consultation on the implementation of construction and assistance in the selection of a contractor.

The main region for the provision of services:

G. Eagle and the Oryol region.

G. Kursk and the Kursk region.

G. Belgorod and the Belgorod region.

Sections of AGSV, ATM, EM of the boiler room, or sections of gas supply automation, heat mechanics automation, boiler room power supply.

Description of sections AGSV, ATM, ES

Section AGSV decoding - automation of gas supply... This section of the AGSV project was developed on the basis of the design assignment and in accordance with the adjacent parts of the project and provides for the installation of a gas metering unit of the SG-EKV-R-0.5-160 / 1.6 type with an electronic volume corrector EK266 / K on the gas pipeline, which allows you to observe the instantaneous parameters of the gas (flow, pressure, temperature) and register them for a certain time.

Structurally, the electronic corrector is attached to the gas meter. The pressure sensor is built into the housing of the electronic corrector. The pressure is tapped through an impulse tube connected to the meter connection. The temperature sensor is inserted into the meter well.

The cable connection of the flow meter and temperature sensor is made at the factory. The corrector is powered by two batteries supplied as part of the corrector. To ensure uninterrupted power supply, the project provides a power supply unit. Data from the corrector interface are transmitted to the control center via a GSM modem.

The connection of the minimum and maximum gas pressure sensors and the shut-off valve and the control and signaling circuits for them are given in section 456-06 ATM.

This project was developed on the basis of the design assignment and in accordance with the related parts of the project. The safety of boilers, regulation of combustion processes are ensured by the boiler and burner automatics, which are supplied as part of the boiler.

The ATM project provides for automatic control of raw water pumps (depending on the pressure in the return pipeline) and boiler circuit pumps (when the boiler is automatically started). All pumps can be controlled manually using buttons from the boiler room control cabinet. ATS is provided for pumps for network, network hot water supply, raw water and circulating water for hot water supply.

The project provides for automatic switching on of the fans when a signal from the gas content of the boiler room is received. In the event of a fire, the fans are automatically turned off.

The boiler room provides for metering of heat energy of network water and hot water with a two-flow two-channel meter of the TEM104-4 type.

The project provides for the regulation of the temperature of the direct supply water to the heating network, depending on the outside air temperature, as well as the temperature of hot water to the consumer, with a two-channel temperature controller of the ART-01.02 type. The temperature controller and temperature sensors are existing (installed in the heat supply unit). Only installation according to the project is required.

This section of EM is designed on the basis of the design assignment and in accordance with the related parts of the project. In terms of the degree of reliability of power supply, the power consumers of the boiler house belong to the 2nd category. Installed capacity of electrical equipment - 52.55 kW (rated capacity and current are 30.21 kW and 62.78 A, respectively).

The input of electricity into the boiler room is carried out by two cables (see external networks), which are connected to the input-distribution device of the ASU boiler room, which provides for an automatic transfer switch and the installation of a direct connection meter.

The distribution of electricity is carried out from the ASU. The power network is carried out with an AVVG cable along the trays and structures of the building. Cable runs to electrical receivers are protected at a height of up to 2.5 meters with a perforated channel.

The project provides for the implementation of working and repair lighting. The working lighting luminaires are powered from the ASU. The repair lighting is powered from a box with a step-down transformer of the YATP-0.25-220 / 36V type and a 36V outlet network. The lighting network is carried out with an AVVG cable along trays, cables and building structures.

The project provides for the installation of explosion-proof lamps, type VZG-200M. It is switched on outside the building. The wiring to the luminaires is carried out in the pipe with a PV3 wire.

ATM technology is a telecommunications concept defined by international standards to carry the full range of user traffic, including voice, data and video signals. It was designed to meet the needs of a digital broadband service network and was originally designed to integrate telecommunication networks. The decoding of the abbreviation ATM sounds like Asynchonous Transfer Mode and is translated into Russian as "asynchronous data transfer".

The technology was created for networks that must handle both traditional high-performance data traffic (such as file transfers) and real-time, low-latency content (such as voice and video). The ATM reference model roughly maps to the three lowest ISO-OSI layers: network, data link, and physical. ATM is the primary protocol used over the basic SONET / SDH (public switched telephone network) link and the Integrated Services Digital Network (ISDN).

What it is?

What does ATM mean for a network connection? It provides functionality similar to circuit-switched and packet-switched networks: the technology uses asynchronous time division multiplexing and encodes data into small, fixed-size packets (ISO-OSI frames) called cells. This is in contrast to approaches such as Internet Protocol or Ethernet, which use variable sized packets and frames.

The basic principles of ATM technology are as follows. It uses a connection-oriented model in which a virtual circuit must be established between two endpoints before the actual communication can begin. These virtual circuits can be "permanent", that is, dedicated connections, which are usually pre-configured by the service provider, or "switchable," that is, customizable for each call.

Asynchonous Transfer Mode (ATM decryption from English) is known as the communication method used in ATMs and payment terminals. However, this use is gradually declining. The use of technology in ATMs has largely been superseded by the Internet Protocol (IP). In the ISO-OSI Reference Channel (Layer 2), basic transmitters are commonly referred to as frames. In ATM, they are fixed in length (53 octets or bytes) and are specifically called "cells".

Cell size

As noted above, ATM decryption is an asynchronous transfer of data, carried out by dividing them into cells of a certain size.

If the speech signal is reduced to packets, and they are forced to be transmitted by reference with heavy data traffic, then no matter what their sizes, they will collide with large full-scale packets. Under normal waiting conditions, they can experience maximum delays. To avoid this problem, all ATM packets or cells are the same small size. In addition, the fixed-cell structure means that data can be easily transferred by hardware without the inherent delays introduced by software switched and routed frames.

Thus, ATM designers used small data cells to reduce jitter (in this case, delay variance) in multiplexing. This is especially important when carrying voice traffic, since converting digitized voice to analog audio is an integral part of the real-time process. This helps the decoder (codec), which requires an evenly distributed (over time) stream of data items. If the next in line is not available when needed, the codec has no choice but to pause. In the future, the information turns out to be lost, because the period of time when it should have been converted into a signal has already passed.

How did ATM evolve?

During the development of ATM, a 155 Mbps synchronous digital hierarchy (SDH) with a 135 Mbps payload was considered a fast optical network, and many plesiochronous digital hierarchy (PDH) channels on the network were significantly slower (no more than 45 Mbps). At this speed, a typical full-size 1500-byte (12,000-bit) data packet would download at 77.42 microseconds. On a low-speed link such as a 1.544 Mbps T1 line, the transmission of such a packet took up to 7.8 milliseconds.

The download latency caused by several such packets in the queue can be several times greater than 7.8ms. This is unacceptable for voice traffic, which must have low jitter in the data stream fed to the codec in order to produce good quality sound.

A packet voice system can do this in several ways, such as using a playout buffer between the network and the codec. This helps to smooth out jitter, but the delay in passing through the buffer requires an echo canceller, even on LANs. It was considered too expensive at the time. In addition, it increased channel latency and made communication more difficult.

ATM inherently provides low jitter (and lowest overall latency) for traffic.

How does this help in network connectivity?

ATM design is for low jitter network interface. However, "cells" were introduced to the design to ensure short queuing delays while continuing to support datagram traffic. ATM breaks all packets, data, and voice streams into 48-byte chunks, adding a 5-byte routing header to each chunk so that they can be reassembled later.

This sizing choice was political, not technical. When CCITT (now ITU-T) standardized ATM, the US wanted a 64-byte payload as it was seen as a good trade-off between large data-optimized data volumes and shorter payloads designed for real-time applications. ... In turn, developers in Europe wanted 32-byte packets, because the small size (and therefore the low transmission time) makes voice applications easier with respect to echo cancellation.

As a compromise between the two parties, a size of 48 bytes was chosen (plus header size = 53). 5-byte headers were chosen because 10% of the payload was thought to be the maximum cost to pay for routing information. ATM technology multiplexed 53-byte cells, which reduced data corruption and latency by up to 30 times, reducing the need for echo cancellers.

ATM cell structure

ATM defines two different cell formats: user network interface (UNI) and network interface (NNI). Most ATM network circuits use UNI. The structure of each such package consists of the following elements:

• The Generic Flow Control (GFC) field is a 4-bit field that was originally added to support ATM interconnection over the public network. It is topologically represented as a Dual Distributed Queue Bus (DQDB) ring. The GFC was designed to provide 4 User-Network Interface (UNI) bits for negotiating multiplexing and flow control among the cells of different ATM connections. However, its use and exact values ​​have not been standardized and the field is always set to 0000.
• VPI is the virtual path identifier (8 bit UNI or 12 bit NNI).
• VCI - virtual channel identifier (16 bits).
• PT - payload type (3 bits).
• MSB - Network Control Cell. If its value is 0, a user data packet is used, and in its structure 2 bits are an explicit forward congestion indication (EFCI) and 1 is a network congestion experience. In addition, another 1 bit is allocated for the user (AAU). It is used by AAL5 to indicate packet boundaries.
• CLP - Cell Loss Priority (1 bit).
• HEC - Header Error Control (8-bit CRC).

The ATM network uses the PT field to denote various special cells for operations, administration and management (OAM) purposes, and to define packet boundaries in some adaptation layers (AALs). If the MSB of the PT field is 0, this is a user data cell, and the remaining two bits are used to indicate network congestion and as a general overhead bit available for adaptation layers. If the MSB is 1, this is a control packet and the other two bits indicate its type.

Some (asynchronous communication) use the HEC field to control a CRC-based framing algorithm that allows cells to be found at no additional cost. The 8-bit CRC is used to correct one-bit header errors and detect multi-bit errors. When the latter are found, the current and subsequent cells are discarded until a cell with no header errors is found.

The UNI packet reserves the GFC field for local flow control or sub-multiplexing between users. This was intended so that multiple terminals could share a single network connection. It was also used to enable two integrated service digital network (ISDN) telephones to use the same basic ISDN connection at a specific rate. All four bits of the GFC should be zero by default.

The NNI cell format replicates the UNI format in much the same way, except that the 4-bit GFC is reallocated into the VPI, expanding it to 12 bits. Thus, one NNI ATM connection can handle almost 216 VCs each time.

Cells and transmission in practice

What does ATM mean in practice? It supports various types of services through the AAL. Standardized AALs include AAL1, AAL2, and AAL5, as well as the rarely used AAC3 and AAL4. The first type is used for constant bit rate (CBR) services and circuit emulation. Synchronization is also supported in AAL1.

The second and fourth types are used for variable bit rate (VBR) services, AAL5 for data. The information about which AAL is used for a given cell is not encoded in it. Instead, it is negotiated or configured on the endpoints for each virtual connection.

Since the initial design of this technology, networks have become much faster. A 1500-byte (12000-bit) full Ethernet frame requires just 1.2 μs to transmit on a 10 Gbps network, reducing the need for small cells to reduce latency.

What are the strengths and weaknesses of this connection?

The advantages and disadvantages of ATM network technology are as follows. Some people think that the increase in communication speed will allow replacing it with Ethernet on the backbone network. It should be noted, however, that increasing the speed alone does not reduce queuing jitter. In addition, the hardware for implementing service adaptation for IP packets is expensive.

At the same time, due to the fixed payload of 48 bytes, ATM is not suitable as a data transmission channel directly under IP, since the OSI layer on which IP operates must provide a maximum transmission unit (MTU) of at least 576 bytes.

On slower or congested connections (622 Mbps and below), ATM makes sense, and for this reason most asymmetric digital subscriber line (ADSL) systems use this technology as an intermediate layer between the physical link layer and the layer 2 protocol, such like PPP or Ethernet.

At these lower speeds, ATM provides the useful ability to carry multiple logic circuits on the same physical or virtual media, although there are other methods such as PPP and Ethernet VLANs that are optional in VDSL implementations.

DSL can be used as a way to access the ATM network, allowing you to connect to many ISPs through a broadband ATM network.

Thus, the disadvantages of the technology are that it loses its effectiveness in modern high-speed connections. The advantages of such a network are that it significantly increases the bandwidth, since it provides a direct connection between various peripheral devices.

In addition, in the presence of one physical connection using ATM, several different virtual channels with different characteristics can function simultaneously.

This technology uses quite powerful tools for traffic management, which continue to evolve today. This makes it possible to simultaneously transmit different types of data, even if they have completely different requirements for sending and receiving them. So, you can create traffic carried out using different protocols on the same channel.

Basics of the functioning of virtual circuits

Asynchonous Transfer Mode (abbreviation ATM) operates as a channel-based transport layer using virtual circuits (VC). It has to do with the concept of virtual paths (VP) and channels. Each ATM cell has an 8- or 12-bit virtual path identifier (VPI) and a 16-bit virtual circuit identifier (VCI) defined in its header.

VCI, together with VPI, is used to identify the next destination of a packet as it passes through a series of ATM switches on its way to its destination. The VPI length varies depending on whether the cell is sent over the user interface or over the network interface.

As these packets pass through the ATM network, the switchover occurs by changing the VPI / VCI values ​​(swapping labels). Although they do not necessarily match the ends of the connection, the concept of the scheme is consistent (unlike IP, where any packet can take a different route to its destination). ATM switches use VPI / VCI fields to identify the virtual circuit (VCL) of the next network that a cell must transit on its way to its final destination. The VCI function is similar to that of the data line connection identifier (DLCI) in the frame relay and the logical channel group number in X.25.

Another advantage of using virtual circuits is that they can be used as a multiplexing layer, allowing different services (such as voice and frame relay) to be used. VPI is useful for reducing the switch table of some virtual circuits that share common paths.

Using cells and virtual circuits to drive traffic

ATM technology additionally includes traffic movement. When the circuit is configured, each switch in the chain is informed of the connection class.

ATM traffic contracts are part of a "quality of service" (QoS) mechanism. There are four main types (and several variants), each of which has a set of parameters describing the connection:

• CBR - Constant Data Rate. Peak Rate (PCR) is indicated and is unchanged.
• VBR - Variable Bit Rate. Indicated is the average or sustainable value (SCR), which can peak at a certain level, for the maximum interval before problems arise.
• ABR is the available baud rate. The minimum guaranteed value is specified.
• UBR - undefined baud rate. Traffic is distributed over the entire remaining bandwidth.

VBR has real-time options, and in other modes serves for "situational" traffic. Incorrect times are sometimes truncated to vbr-nrt.

Most traffic classes also use the concept of cell tolerance variation (CDVT), which defines their "congestion" over time.

Data transmission control

What does ATM mean in view of the above? To maintain network performance, VLAN traffic rules can be applied to limit the amount of data transferred at connection entry points.

The reference model validated for UPC and NPC is the General Cell Rate Algorithm (GCRA). Typically, VBR traffic is usually controlled using a controller, as opposed to other types.

If the amount of data exceeds the traffic determined by the GCRA, the network can either discard cells or flag the Cell Loss Priority (CLP) bit (to identify the packet as potentially redundant). Most of the security work is based on sequential monitoring, but this is not optimal for encapsulated packet traffic (since dropping one 1 would invalidate the entire packet). As a result, schemes such as Partial Packet Discard (PPD) and Early Packet Discard (EPD) have been created that are capable of discarding a whole series of cells until the next packet begins. This reduces the number of useless pieces of information on the network and saves bandwidth for full packets.

EPD and PPD work with AAL5 connections because they use the end of the packet marker: the ATM user interface indication (AUU) bit in the Payload Type field of the header, which is set in the last cell of the SAR-SDU.

Traffic shaping

The basics of ATM technology in this part can be presented as follows. Traffic shaping typically occurs at the network interface card (NIC) in the user equipment. At the same time, an attempt is made to ensure such conditions where the flow of cells on the VC will correspond to its traffic contract, that is, the units will not be discarded or reduced in priority order in the UNI. Since the reference model specified for traffic management in the network is GCRA, this algorithm is commonly used for shaping and routing data.

Types of virtual circuits and paths

ATM technology can create virtual circuits and paths both statically and dynamically. Static diagrams (STDs) or paths (PVPs) require a diagram to be composed of a series of segments, one for each pair of interfaces it passes through.

PVP and PVC, while conceptually simple, require significant effort in large networks. They also do not support rerouting a service in the event of a failure. In contrast, dynamically constructed SPVPs and SPVCs are constructed by specifying the characteristics of a schema (service "contract") and two endpoints.

Finally, ATM networks create and remove Switched Virtual Circuitry (SVC) at the request of the end piece of equipment. One application for SVC is to carry individual telephone calls when the switch network is interconnected via ATM. SVCs have also been used when trying to replace ATM LANs.

Virtual routing scheme

Most ATM networks that support SPVP, SPVC, and SVC use a Private Network Node or Private Network-to-Network Interface (PNNI) protocol. PNNI uses the same shortest path algorithm that OSPF and IS-IS use to route IP packets to exchange topological information between switches and to select a route through the network. PNNI also includes a powerful summarization mechanism to enable very large networks, as well as a Call Access Control (CAC) algorithm, which determines that sufficient bandwidth is available along a proposed route through the network to meet VC or VP service requirements.

Receiving and connecting to calls

The network must establish a connection before both sides can send cells to each other. B is called virtual circuit (VC). This can be a permanent virtual circuit (PVC), which is created administratively at the endpoints, or a switched virtual circuit (SVC), which is created as needed by the transmitting parties. The creation of the SVC is signaling driven, in which the requester indicates the address of the receiving party, the type of service requested, and any traffic parameters that may be applicable to the selected service. The Network will then confirm that the requested resources are available and that a route exists for the connection.

ATM technology defines the following three levels:

• ATM adaptation (AAL);
• 2 ATM, roughly equivalent to OSI data link layer;
• physical, equivalent to the same OSI layer.

Deployment and distribution

ATM technology became popular with telephone companies and many computer manufacturers in the 1990s. However, even towards the end of this decade, the best price and performance of Internet Protocol products began to compete with ATM for real-time integration and packet network traffic.

Some companies still focus on ATM products today, while others provide them as an option.

Mobile technology

The wireless technology consists of an ATM core network with a wireless access network. Cells are transmitted here from base stations to mobile terminals. The mobility functions are performed on an ATM switch in the core network, known as a "crossover", which is similar to the MSC (Mobile Switching Center) of GSM networks. The advantage of ATM wireless communication is its high throughput and high handover speed, performed at layer 2.

In the early 1990s, some research laboratories were active in this area. The ATM Forum was established to standardize wireless networking technology. It was backed by several telecom companies, including NEC, Fujitsu, and AT&T. ATM mobile technology aims to provide high-speed multimedia communication technologies capable of delivering mobile broadband beyond GSM and WLAN networks.

ATM

ATM

ATM(from ATM, sometimes ATM from English Automated teller machine) is a software and hardware complex designed for automated issuance and acceptance of cash both with the use of payment cards and without, as well as performing other operations, including payment for goods and services, drawing up documents confirming the relevant operations.

The procedure for using ATMs in making payments with bank cards in Russia is determined by the Regulation of the Bank of Russia on the issue of bank cards and on transactions performed using payment cards No. 266-P dated December 24.

The cost of a modern ATM depends on functionality and manufacturer, and can range from 15 to 50 thousand dollars.

Story

The prototype of the first ATM was invented by Luther George Simjian (eng. Luther george simjian ) back in 1939. The device dispensed cash, but at the same time it could not write it off from the account: the device was not connected with the bank. Simjan offered to try out the invention of the City Bank of New York, but six months later the bankers returned the car, saying that they did not see the need for it. Simjan's invention was forgotten for almost 30 years and was refined only in the late 1960s.

The first ATM to dispense cash was installed on June 27 in the Anfield area in north London (UK) at a branch of the British bank Barclays. Its inventor was the Scotsman John Shepard-Barron, who worked for De La Rue, a British manufacturer of paper for banknotes in more than 150 countries.

Plastic cards did not exist at that time, and special vouchers were used to withdraw money, which had to be obtained in advance from the bank. A few years later, another Scotsman, James Goodfellow, came up with the idea of ​​using a secret PIN code to protect against unauthorized access to bank accounts, and the first plastic cards with a magnetic stripe appeared in the United States.

The introduction of ATMs was gradual. In 1971, the first types of ATMs were in use in about 35 American banks. Citibank was the first bank to start installing ATM machines everywhere in 1972. By 1975, just over 5,000 ATMs were operating in the world, of which about 3,140 were in 534 American banks.

In 1972 Bank Lloyds introduced the first on-line ATMs in the UK called Cash-Point. They were developed by IBM and accepted magnetic stripe plastic cards.

The development of telecommunications made it possible to build ATM networks, which were used by several banks at once. This happened for the first time in 1972-1975. in USA. Several hundred ATMs from 18 banks in Washington state were networked under the name Exchange.

Operating principle

After loading the card into the ATM card reader, the cardholder is asked to enter the secret code (PIN code) to authorize the cardholder. Further, a selection of available operations is offered (when selecting an operation, a PIN code may also be requested; this depends on the specific settings of a particular ATM). After selecting the operation, the ATM encrypts the received information (the contents of the magnetic stripe / chip, the entered PIN code, the requested operation) and transmits the data to the processing center of the acquiring bank (the bank serving the ATM).

ATM

The acquiring bank sends a request for the operation to the payment system. The payment system routes the request to the issuing bank (the bank that issued the card) and, having received consent or refusal (authorization code), sends the ATM commands to execute or reject the request. At the same time, all actions for sending a request, processing a response to a request, issuing / accepting money from cassettes are recorded, which allows an investigation if the operation is contested.

Since the PIN-code is known only to the cardholder, transactions confirmed by the PIN-code are considered to have been performed directly by the cardholder.

Worldwide use

There is no exact statistics on the number of ATMs in use in the world. However, according to the ATM Manufacturers Association (eng. ATM Industry Association), more than 2.3 million ATMs are installed in the world (as of November 2011).

Diebold and NCR are major ATM vendors in the US, said Kartik Mehta, an analyst with Cleveland-based Northcoast Research. Diebold of North Canton, Ohio controls 46% of the market share. The share of NCR in Duluth, Georgia is slightly less at 43%. Other ATM makers, most notably Wincor Nixdorf of Austin, Texas (a subsidiary of Wincor Nixdorf AG of Paderborn, Germany), control the remaining 11%.

ATM fraud

In recent years, along with the development of the ATM network, the number of cases of ATM fraud is growing - the unlawful use of ATMs to steal money from the accounts of plastic card holders.

The ways

There are several dozen methods of misappropriation of money from another person's card account using ATMs, different in organization and technological level. According to APACS (Association for Payment Clearing Services - United Kingdom), the following are the most common:

• Use of a stolen card and the PIN-code disclosed by the holder (including cases when the PIN-code is stored next to the card or written on it).
• "Friendly fraud". Using the card through free access by family members, close friends, work colleagues. Also involves the disclosure of the PIN.
• Peeping a PIN over the shoulder and then stealing the card is the simplest but widespread method.
• The Lebanese Loop. The card feed window is blocked so that the card is jammed. When you try to insert a card into an ATM, it gets stuck. The attacker, who has previously spied on the PIN, sympathizes and recommends to urgently go and call the bank or service department. As soon as the owner leaves, the perpetrator removes the card, releases the ATM window and withdraws the money.
• Fake ATMs. A rather rare method that requires technical equipment. Fraudsters make fake ATMs that look like real ones, or they remake old ones and place them in crowded places. Such an ATM accepts a card, requires entering a PIN code, after which it issues a message about the impossibility of issuing money (under the pretext of a lack of money in the ATM or a technical error) and returns the card. The ATM copies data from the card and PIN, which allows fraudsters to subsequently make a duplicate and use it to withdraw money from the client's account.
• Copying the magnetic stripe (skimming) with dummy readers. Such devices are installed on an ATM (the reader is on the slot for accepting a card, an additional keyboard is used to cover the real one). When using such an ATM, the reader saves data from the cards inserted into the ATM, and the keyboard saves PIN codes. As in the previous case, the stolen data is enough to produce a duplicate card and withdraw money from the owner's account.
• False PIN-PAD (a device for entering a PIN code in payment terminals), or an additional element on an electronic lock in a room with an ATM that can be opened with a card.
• Installation of miniature TV cameras near the ATM to steal PIN-codes. Such a camera can be disguised by an object installed next to it or attached to an ATM or a wall next to it.

In 2011, there were reports of another theoretically possible way to steal PIN codes using an ATM: using a high-sensitivity infrared camera. An attacker in the queue takes a snapshot of the keyboard on which the previous user typed the PIN. The keys that have been touched are somewhat warmer, with the last pressed key being warmer than the last but one, and so on. The success of this method, however, depends on the type of keyboard (metal keyboards have a higher thermal conductivity and the temperature of their keys is quickly equalized) and on whether the client has not typed anything else on the keyboard (for example, an amount). To avoid removing the PIN-code by thermal imprint, it is enough to put your palm on it for a short time after working with the keyboard.

Prevalence

The scale of ATM fraud in the world is already very large, losses from it in the United States amounted to 2.79 billion dollars per year at the end of May 2005 (Gartner), in the UK in 2006 - 61.9 million pounds. In Latin America, the number of ATM-related crimes increased by 15% between 2001 and 2005. In Eastern Europe and the former USSR, the problem is less acute due to the lower use of electronic means of payment, but, nevertheless, the level of crimes related to electronic cards is also growing. According to official data, losses from fraud in Ukraine amount to 0.06% of the annual card turnover (UAH 90 million in 2006). According to unofficial estimates of specialists from the National Bank of Ukraine, in reality, this value is up to one percent of the total turnover of cards, that is, the actual volume of theft in 2006 amounted to about one billion hryvnia.

Safety rules when working with an ATM

• If you are used to withdrawing money from the same ATM, remember its appearance. When changing the appearance of the card slot, it is better not to even insert it.
• Cover the keyboard with your hands when entering the PIN. Various objects near the screen are most likely a disguise for a hidden camera.
• The most protected ATMs located on the territory of the bank, as they are regularly examined by bank employees. However, this protection is not absolute.

Sources of

Literature

• Pavel Yurzhik Payment cards. Encyclopedia 1870-2006 = Platebni karty: Encyklopedie 1870-2006. - M .: "Alpina Publisher", 2007. - 296 p. - ISBN 5-9614-0436-6

Links

• The first Russian site dedicated to the repair and maintenance of ATMs. ...