Eavesdropping perfect

The ultimate listening device almost everyone has in their pocket. This mobile phone (in 2008. There were registered in Poland 44mln). In this post I'd like to have some subject which usually no one does wonders.

It will be a little technical, but I think this knowledge necessary to understand how things really work and how to use this knowledge. If there is a positive response in subsequent entries I will try to bring the issues associated with the monitoring of electronic media, standard (including paper) technology, RFID chips and technologies "non-lethal" crowd-control.
Let's get to the merits

At the moment one and nabardziej widespread communication tools is an invention Graham Bell (although some people argue whether or not it was an invention of the Russian inventor Elisha Gray, who de'facto Bell invented the telephone before, what are the documents, but Bell's patent was made earlier, which prevailed in lawsuits). Today's telephone very different from that invented by Bell and Grey, since then there has been a significant leap in technology. Currently, the most common is the mobile phone.

A little history of GSM

With the outbreak of the Second World War there was a need for systems that enable communication between individuals involved in the fighting. Very quickly they constructed many receivers and transmitters for communication mobile, while making tremendous progress on their functioning and structure. At the end of the war most of the ships, aircraft, and even tanks was equipped with its own communication systems. Radio communication devices began to be produced on a large scale. Thus opening the route for the development of a real market for mobile communications. Shortly after the war, the United States began to successfully introduce mobile systems for sectors such as police, fire, energy, water supply and gas and transportation. In 1946, St. Louis, the merger of mobile telephone networks with the fixed telephone network.

Soon realized that the solution using a single transmitter very limited capacity of the system. For the purpose of mobile communications around the town could use a few channels. The demand was much higher, because scientists quickly take the work on the more perfect solutions. In the late forties in the lab Bella rise to the concept of mobile telephony. The new solution allowed to increase system capacity by dividing the whole area into smaller units called cells which were supported by low-power transmitters.

The area is divided in this way it was possible to reuse the same frequencies in different cells, thereby increasing the number of stations it serves. It was not possible to use the same frequency in cells adjacent to each other, as this led to the so-called. co-channel interference, which caused disruption and made it impossible to achieve the required quality of service. We found that the occurrence of interference is not dependent on the distance between cells that use the same frequency, and the ratio of the distance to the radius of the cells. Because the cell radius depends on the transmitter used, the ratio of the distance to the radius can be controlled by system engineers. Engineers working on the development of the mobile network, knowing that the reduction in cell size leads to increased system capacity, assumed in theory, the possibility of building a network of several thousand cells, which could handle up to one million users. The construction of such a network from the beginning would be extremely expensive, and therefore it was decided to design the system, dividing the area of ​​a few large cells which eventually had to be divided into smaller and smaller. This technique offered many advantages, allowing the system development time and increasing number of users with increasing interest. During the work on the new system came another problem related to the migration of users from the area of ​​one cell into the other. At small cell sizes such changes were taking place very quickly, especially for users with a means of transport.

To move from one cell to another does not affect the continuity of transmission, a technique of switching channels (called. Hand-off). The phone was supposed to be equipped with a central control device on the network connection status, as well as the commutation switching system connection to the area of ​​another transmitter. This required the development of several techniques still control the current location of the mobile station. There was this too much trouble and in 1947 work on the first proposal for a cellular system have been completed. Although the first suggestion of mobile telephony appeared in the late forties, at the launch of the first systems still had to wait about 3 years. Establish an efficient mobile network require allocation of new spectrum, which is decided in the United States only in the sixties.

In 1976 in New York launched a cellular system that allows simultaneous obsłuśenie 12 calls. For this "luxury" when used by 500 users, with a further 3,700 were waiting for registration. The first analog cellular technology appeared in the 80s in Scandinavia. In a slightly modernized form it works even today in the Polish analogue Centertel. Milestone erected in 1982, when under the European CEPT agreement created a working group called Groupe Spéciale Mobile, which in French means "team for Mobile Communications", abbreviated as GSM. The objective of this team was to develop a standard phone system common to the whole of Western Europe. When it turned out that the capacity of analog cellular networks began to run out, the work of the GSM band gained momentum. This issue was raised at a meeting of the leaders of the member countries of the European Community in December 1986 year. As a result, the talks booked two bands of frequencies in the 900 MHz band for exclusive use at destined to develop mobile radio system.

Next year is a period of standardization and a number of regulations related to the introduction of new systems which on a larger scale began to appear in the eighties. In the United States it was the system (AMPS called. Advanced Mobile Phone Service), and in Europe: Scandinavian system NMT (ang. Nordic Mobile Telephone System), the European version of AMPS called TACS (ang. Total Access Communications System) and two lesser-known architecture: R2000 French and German C-450. These systems were analog systems and are referred to today as the first-generation systems. Since its introduction, the rate at which increased their popularity, it was a surprise to many experts. In a short time their services in Europe alone benefited hundreds of thousands of subscribers. The growing very rapidly the number of users meant that the capacity of analog systems began to run out already in the eighties. There is also a need to develop a pan-European mobile system. Existing first-generation systems operate completely independently of each other, which prevented communication between subscribers of two different systems. The problem of limited capacity analogue networks, as well as the need for an operating system throughout Europe house developments have given rise to a new system - GSM.

Until 1986 it was already known that arise plan whose system will be fully digital, because it is more efficient due to a higher quality of transmission and the possibility of introducing new services. In September of 1987 he established a life of GSM Memorandum of Understanding (MoU GSM), the umbrella organization of future operators of GSM systems. The aim of the GSM MoU was to coordinate the standardization work, planning the deployment of services and the development of pricing policies and mutual settlements between operators. In 1988, he established the European Telecommunications Standards Institute (ETSI). The standardization work of the GSM continued through ETSI, and the band GSM has become one of the working groups ETSI. GSM shortcut has been given a new meaning Global System for Mobile Communications, which means "global wireless communications system," which hardly presage ponadeuropejski system coverage. Although the basic version of the system - called (GSM. Global System for Mobile communications) was ready as early as 1989, planned earlier launch of the system was delayed. The reason was the lack of developed on time certification test for testing the GSM network elements. The first GSM system was unveiled at TELECOM in Geneva in October 1991. Within a few months the system was introduced in several dozen countries on four continents, making it the most popular mobile phone system in the world. In 1990, at the request of the United Kingdom produced recommendations for versions of GSM-frequency 1800 MHz designed for densely populated urban areas. The first commercial system was launched in 1992. These versions are called DCS 1800, and in 1997 the name was changed to the GSM 1800.

The first version of the GSM standard in 1990 allowed the use of essential services, ie voice calls. The initial version of the GSM standard in 1991 received the name of the GSM Phase 1. In 1995, work was completed on Phase 2 of the GSM standard. In Phase 2 the range of services has been greatly expanded, also introduced some improvements associated with the SIM card service. It also defined in a more efficient algorithm coding speech signals (whose fracture is no longer difficult). In the second half of the 90s ETSI created the so-called. Faze 2+. The next step was a Phase 3 (3G). Currently, Japan is working on the implementation of Phase 4 (4G).

What kind of information circulating on the GSM network?

Cells - The GSM system is divided into cells served by base stations, commonly referred to as BTS'ami (Base Transceiver Station). Each of them is associated with the identification number of BSIC that can distinguish individual cells. Each also has an associated global number CGI, which can distinguish within the areas (cells are grouped into areas, each area of ​​its number LAI) of the cell which said called subscriber.

Terminals - name that identifies a mobile station. They can be both stations transportable, portable, pocket (the most popular GSM phones), wireless telephones, PBXs or modules. Each of the GSM terminals have assigned him international unique IMEI number, which is used to keep track of which terminals are currently using the service BTS allows the lock a stolen or not approved terminal. This number is stored in the mobile station, and the register EIR, of which more later. The IMEI number can be seen on the phone normally during battery replacement. It is printed on the label.

Each subscriber addition is assigned MSISDN. It is an international subscriber number, which allows you to find the nearest panel GSMC transit for the desired GSM system.

HLR - memory cell of the mobile station, in which to store the MSISDN, IMSI international subscriber number used to identify a subscriber within a GSM network. This is the number we would use when exchanging phone numbers with friends (this number is trównież in another register AUC and SIM card, as well as in the register VLR base station), key identification, status (eg blocked by the service provider), the list bearer services, the current location of the subscriber with an accuracy to the MSC (MSC - the panel moving system - Mobile Switching Centre)
Register VLR - This register is located on the SIM card. It is stored in the IMSI and MSRN that identifies the temporary address of the mobile station (which is where we are in the network)
Number TMSI - a coded number, IMSI number, assigned at the time of the first notification in the GSM network (when we unpack our new phone and / or the card, run it, after the merger with the parent GSM network in the feuds time nastpuje encrypting the IMSI number in the registry TMSI) .
Each terminal can be in three states: off (station does not recognize any signals, is not participating in the movement) sleep (terminal turned on, informs about the position, waiting for the call to), active (terminal turned on, it participates in the merger).

The transition from the state wyaczonego terminal to a running runs in 3 steps: the terminal detects an incoming voice call signaling channel, selects the strongest base station, and stores the number of LAI. If the station number is equal numerowu was turned off, the register VLR base station changes the indicator terminal from OFF to ON.

VLR (VLR - Visitors Location Register) - register is located at the base station and contains data on all mobile stations associated with the MSC. It stores the state of the terminal, the identifier area in which a mobile station (phone), address HLR, additional information (parameters procedures, encryption and authentication, subscriber type, etc). It also includes information about all mobile stations

Turning off the terminal sends a signal to the network is disconnected. From now on, no signal will be transmission to the terminal.

Periodic call location - each terminal periodically transmits to the base station its readiness to receive calls. If for some time the base station receives such a signal from the terminal considers him off (OFF).

SIM card - this is a stand-alone single-chip microcomputer with its own processor, RAM and ROM Pamić and the system interrupts. Basic features include encryption key generation call, keep a list of contacts, text messages, data security PIN and PUK codes.

Several major on the SIM card - secure PIN / PUK does not constitute any obstacle to a specialized technician. Erasing SMS or a call list of the SIM card (with the camera) usually does not delete them from the SIM card, which can store huge amount of data. It sets only the removal of the tag, which means that you do not see them listed in your phone. The only (though not always to the end effective) way to block the card before anyone is her break.

Location GSM

First, determine our position based on a GSM phone is not a problem for mobile network software. Positioning accuracy portable station at the moment is a few meters (which was going to use Google to not have to use in the planned to launch their phones with the system GoogleMaps install GPS modules). At any time based on motion vector it is also identified code (which is likely to have turned his head toward), which soon will be used to provide subscribers with ads shops, near where the pass. Such systems are already being tested in Europe as well. Location of children using the GSM modułw already offered by various mobile networks. Exactly the same principle can track vehicles fitted with the GSM locators. No need to purchase expensive GPS devices.

There are 4 categories of location:

Based on the network - network infrastructure calculates the position of the receiver
Based on the terminal - all calculations are performed by the receiver. This is due to the considerable complexity.
Aided by network - the calculations are done by the receiver using data transmitted over the network. That's how GPS network. Knowing some reference values ​​transmitted from satellites, the receiver calculates its position.

Powered by terminal - receiver measures the reference signals transmitted across the network, refers to her report, and a network calculates the position of the receiver. This method is used in GSM networks
The location of wireless devices is performed by three techniques:
Proxymacja - a technique involving the location of the camera by logging on to the access point with the already known location. The same technique is used to locate a computer plugged into the access point.

Triangulation - it is a method for determining the position of the receiver using triangulation based on his position at least three base stations to which the receiver is connected. 3 stations are enough to determine the position of a receiver / transmitter with an accuracy of up to a meter. How does it work?
Each base station has a specific geographical location. The phone by logging on to the network at the same time is connected to three base stations (if one thinks that only the nearest, it's wrong). Clocking signal flow between each base station and receiver / transmitter can be quickly and precisely determine the position of such camera in 2D space.

GPS - position in 3D space, it is possible to determine using only the GPS system, in which m receiver determines the location of the at least four base stations (satellite).
Wiretapping
Wiretapping must be divided into two categories
based on the terminal - implemented directly by phone
based on network
external
First we need to deny certain circulating information. Eavesdropping is not a number, I know a number of subscribers (of which we call). Overhears a phone's IMEI number. This ensures wiretapping even after changing or removing the card. As I wrote above, the network stores all the data, each statement IMEI and IMSI, and knows exactly when and where was our devices and cards that they have used. It does not matter if the card is in the camera. Phone after turning, regardless of whether the SIM card is in it or not, declares its willingness to connect all base stations within range. This means that such information when the camera is stored in the BTS stations all mobile networks operating in which the terminal was started (in our case it is the infrastructure of Polkomtel [Plus] Orange [formerly Centertel, then Idea] and EraGSM). Only after the card is detected, it is read from the network ID and the camera performs an attempt to log on to a particular network. Similarly: switch your phone off powosuje not disconnect the camera from base stations is performed only log off from the network. The camera itself goes to sleep, but still every few dozen minutes communicating with stations of BTS and sends them ready signal (and hence its position).
Eavesdropping based on the terminal is implemented by running over the network, secretly installed in the terminal microphone. Officially, none of the manufacturers do not admit to the installation of such curiosities in the same hardware, but this is the open secret: no one about it openly does not say, but we all know that the cameras have extra hidden features that are "facilitation" for special services (indeed, quite a few with examples of such use mechanisms built in GSM phones). But does it really have to be implementations in hardware? In the official sale they are already mobile systems (or there is the possibility of installing such a system in the supplied camera) to enable them wiretapping known. "Privileged number". With it, you can read text messages, podsuchiwać everything that is going on without making a call, podsuchiwać already established connection like. Just donate a aparacik wife, employee and have it under control.
What's more, the same way you can not only turn on the microphone, but also a camera phone. At present all new phones they already have two cameras: one rear camera with higher resolution, one on the panel facing the caller and used to teleconference. Surveillance capabilities of these methods are simply fantastic and for a cellular network available 'at the snap of your fingers. " As a rule, however, such methods Others are "reserved" for an "important objectives".
Here the only way to defend is to physically remove the battery and thus cut off the power supply.
And this is a weak point. Though perhaps in a few years there will be no telephones with replaceable batteries? Such a device is for example: Apple's iPhone, which recently making an outstanding career.

Eavesdropping is based on a network is realized when you connect. Seemingly everything is encrypted, but each call passes through a central Web servers. At this point, nothing needs to be installed specifically for the phone. And this method is the most commonly performed eavesdropping.

Eavesdropping exterior is carried out by mobile external devices. No problem, you can from a distance of up to 1000m to read clearly the image of a computer monitor or a TV (that was 20 years ago in the case of CRT monitors. Currently, we have low carbon technologies, LCD, well, but the eavesdropper's not going back in development, but continue to invest and learn , truth ?). Your best bet is to stock up on two devices: IMSI Catcher [by ABW officers called swallow that directed to the appropriate object impersonating a real station of GSM and thus takes on its merger] (spoof the base station in close proximity to the camera), or set to cloning GSM cards. The other option GSM eavesdropping outside you can tell by reading this short article of: http://www.hcsl.pl/2010/05/uwaga-pojawi-sie-gotowy-zestaw-do.html (link is external)
Dlacego GSM is the most perfect spy?

Voice transmission in GSM does not transfer data in analog form, but is divided into sections 20ms, because the parameters of the larynx, tongue, teeth, nose does not move in the time range (more on this at [I know, I know, Wikipedia is not reliable source of information ...]: http://pl.wikipedia.org/wiki/Transmisja_g%C5%82osu_w_sieci_GSM (link is external)). In general, the idea is that the GSM phone has standard equipment on extremely sensitive electret microphone, and the design itself voice codec in GSM network is tailored specifically to human speech, which weeds out all the unwanted sounds (background noise, the sound of lawn mowers, etc., like microphones laryngeal ), enhancing human speech, and that hardware. Besides wiretapping based on GSM networks do not have to be installed at somebody physically. Just install the appropriate software for major server provider and the case. As a result, this device is an ideal tool for eavesdropping.

Conclusion

Bottom line, unfortunately, is that it is best not to have a mobile phone, and if you already have, we should remove the batteries before an important meeting. For more zaaawansanych cameras there is also the issue of hackers, crackers and the possibility of infection with a virus, data loss, and the like danger (dilemmas will soon also concerned cars). To avoid this, do not use the Mega Promotion (free directories, etc.), have the least advanced and most unpopular phone, because the greater the amount implemented in the technology, the more popular the camera or installed in the system, the greater the possibility podsuchu , burglary, acquisitions, etc.
Knowing how it all works, you can use this knowledge in practice. But it's a completely different story.

ps: also important to emphasize that the possibility to connect to the GSM network of the aircraft decreases dramatically with altitude and at cruise. In addition, the aircraft itself is a kind of Faraday cage, shielding a large part of the GSM signal. In connection with this matter carried out in research, manufacture so many calls from the decks of aircraft allegedly kidnapped Sept. 11 was technically and statistically impossible. Currently on board (from approx. 2007), mounted local base stations, and connections are realized outside the aircraft via satellite. As if by chance a few months earlier Los Alamos laboratory has revealed that he is in possession of voice morphing system, through which it is possible to simulate each voice based on only the few minutes of the sample (http://www.washingtonpost.com/wp-srv/national/dotmil/ arkin020199.htm (link is external)). Conclusions I leave with you. Although it is of course another "theory" conspiracy. Truth ?