118 G.O. Onwodi, K.I. Nkuma-Udah and F.B. Osang
Tempest: A Surveillance Technology in the Service of Humanity
*G.O. Onwodi 1, K.I. Nkuma-Udah 2 and F.B. Osang 1
1School of Science and Technology, National Open University of Nigeria, Lagos, Nigeria 2Department of Biomedical Technology, Federal University of Technology, Owerri, Nigeria
(Received April 25, 2010; Revised October 25, 2010; Accepted November 26, 2010)
TEMPEST was coined as a codename for the National Security Agency (NSA) of USA operation to secure electronic communications equipment from potential eavesdroppers and vice versa the ability to intercept and interpret those signals from other sources. It is a major surveillance system of the NSA. Surveillance, which is the monitoring of the behavior, activities, or other changing information, usually of people and often in a sur- reptitious manner, is very useful to governments and law enforcement to maintain social control, recognize and monitor threats, and prevent/investigate criminal activity. It is generally considered to be a weapon with which to fight organised crime or terrorism. Various types of surveillance systems exist for use by agencies. These systems are sometimes accepted in the society because of the belief that these tools protect society from terror- ists and criminals. There are also legal aspects of surveillance. As a result some civil rights groups oppose sur- veillance as a violation of people's right to privacy. The TEMPEST technology, emissions or emanations from electronic components of electromagnetic radiation in the form of radio signals constitute a major surveillance system. These emanations or signals on a target can be propagated by four basic means: electromagnetic radia- tion, line conduction, fortuitous conduction and acoustics. They are then used to intercept the electro-magnetic waves over the air and can capture signals through the walls of computer screen. The tempest technique en- ables the software on a computer to control the electromagnetic radiation it transmits. This can be used for both attack and defence. The use of Tempest technology has in many ways helped NSA of USA to overcome the worst enemy of mankind - terrorist invasion. Nigeria is expected to embrace the challenge of preventing TEMPEST attacks of her military and diplomatic data by improving and updating its military surveillance sys- tems. Doing this would be a great service to the Nigerian nation.
Keywords: TEMPEST, surveillance, service, humanity, computer, technology
1. Introduction if intercepted and analyzed, may disclose the infor- mation transmitted, received, handled, or otherwise TEMPEST (often used to mean Transient Electro- processed by any information-processing equipment magnetic Pulse Emanation Standard) was coined in [3]. the late '60s and early '70s as a codename for the Na- Compromising emanations consist of electri- tional Security Agency (NSA) of USA operation to cal, mechanical, or acoustical energy intentionally or secure electronic communications equipment from unintentionally emitted by any number of sources potential eavesdroppers and vice versa the ability to within equipment/systems which process national intercept and interpret those signals from other security information. This energy may relate to the sources [1,2]. original encrypted message, or information being It is a codename referring to investigations processed, in such a way that it can lead to recovery and studies of compromising emanations or emis- of the plaintext. The term "compromising emana- sions (CE). Compromising emanations are defined tions" rather than "radiation" is used because the as unintentional intelligence-bearing signals which, compromising signals can, and do, exist in several
graph io ica B l n C a e c n i t r r f e *Corresponding author email: [email protected] A a b c
**D y
i ABC Publishers Inc r h e p c r t o g ri io e B s n of Africa Afr J Med Phy, Biomed Eng & Sc, 2010, 2, 118 - 126 119 forms such as magnetic- and/or electric field radia- tivities, or other changing information, usually of tion, line conduction, or acoustic emissions. people and often in a surreptitious manner. It most Laboratory and field tests have estab- usually refers to observation of individuals or groups lished that such CE can be propagated through space by government organizations. and along nearby conductors. The intercep- The word surveillance may be applied to tion/propagation ranges and analysis of such emana- observation from a distance by means of electronic tions are affected by a variety of factors, e.g., the equipment (such as CCTV cameras), or interception functional design of the information processing of electronically transmitted information such as equipment; system/equipment installation; and, envi- internet traffic or phone calls [5,6]. It may also refer ronmental conditions related to physical security and to simple, relatively no- or low-technology methods ambient noise. such as human intelligence agents and postal inter- The NSA of ception. USA with her allies, including the United Kingdom, Surveillance is very useful to govern- Australia, New Zealand and Canada used the Tem- ments and law enforcement to maintain social con- pest technology to enable interception of messages trol, recognize and monitor threats, and pre- or communications for surveillance and security pur- vent/investigate criminal activity. It is generally con- poses. Interception of communications is a method sidered to be a weapon with which to fight organised of spying commonly employed by intelligence ser- crime or terrorism. Though, it can, however, have a vices of the various governments of the world. darker side, namely that of industrial espionage, vio- The Tempest is developed with the high- lation of privacy, or both [7]. est computing power of computers connected Computer programs such as ADVISE; through the satellites all over the world [4]. The technologies such as high speed surveillance com- main technology behind the Tempest is the fact that puters and biometrics software; and laws such as the any electronic or electrical device emits electromag- Communications Assistance For Law Enforcement netic radiations or waves of specific key when it is Act of the USA have been used by governments to operated. Those electromagnetic waves can be re- monitor the activities of their subjects and terrorist produced by tracing with the powerful equipment tendencies. and powerful filtering methods to correct the errors while transmitting from the equipment . 2.1 Types of Surveillance However, there are certain limitations Computer surveillance imposed on this method of surveillance system. This Computer surveillance mainly involves the monitor- depends in particular, on worldwide interception of ing of data and traffic on the Internet. Some coun- satellite communications. Although in areas charac- tries like the United States of America under the terised by a high volume of communications only a Communications Assistance For Law Enforcement very small proportion of those communications are Act (CALEA), require all phone calls and broadband transmitted by satellite. Internet traffic (emails, web traffic, instant messag- Communications cannot be intercepted ing, etc.) to be available for unimpeded real-time by earth stations, but only by tapping cables and in- monitoring by Federal law enforcement agencies [8]. tercepting radio signals. Though, one constraint on Since there is far too much data on the the use of tempest is that the number of personnel Internet for human investigators to manually search required for the final analysis of intercepted commu- through, automated internet surveillance computers nications, which imposes further limitations. sift through the vast amount of intercepted internet traffic and identify and report to human investigators 2 Surveillance Systems traffic considered interesting by using certain words or phrases, visiting certain types of web sites, or Surveillance is the monitoring of the behavior, ac- communicating via email or chat with suspicious
120 G.O. Onwodi, K.I. Nkuma-Udah and F.B. Osang individuals or groups. Notable examples of com- mation such as personal interests, friendships & af- puter surveillance include Carnivore, ECHELON filiations, wants, beliefs, thoughts, and activities. and TEMPEST. Biometric surveillance Telephones surveillance Biometric surveillance refers to technologies that The USA CALEA Act apply also to telephones. In measure and analyze human physical and/or behav- telephone surveillance, human agents are not re- ioral characteristics for authentication, identification, quired to monitor most calls. Speech-to-text soft- or screening purposes. Examples of physical charac- ware creates machine-readable text from intercepted teristics include fingerprints, DNA, and facial pat- audio, which is then processed by automated call- terns. Examples of behavioral characteristics include analysis programs or companies which search for gait (a person's manner of walking) and voice certain words or phrases, to decide whether to dedi- [11,12]. cate a human agent to the call. Another form of behavioral biometrics, Mobile phones are also commonly used based on affective computing, involves computers to collect location data. The geographical location of recognizing a person's emotional state based on an a mobile phone (and thus the person carrying it) can analysis of their facial expressions, how fast they are be determined easily (whether it is being used or talking, the tone and pitch of their voice, their pos- not), using a technique known multilateration to cal- ture, and other behavioral traits. This might be used culate the differences in time for a signal to travel for instance to see if a person is acting "suspicious" from the cell phone to each of several cell towers (looking around furtively, "tense" or "angry" facial near the owner of the phone. expressions, waving arms, etc.). Facial thermographs are currently in devel- Surveillance cameras opment, which allow machines to identify certain Surveillance cameras have been installed by the mil- emotions in people such as fear or stress, by measur- lions in many countries and are monitored by auto- ing the temperature generated by blood flow to dif- mated computer programs instead of humans. They ferent parts of their face. Law enforcement officers are video cameras used for the purpose of observing believe that this has potential for them to identify an area. They are often connected to a recording de- when a suspect is nervous, which might indicate that vice, Internet Protocol network, and/or watched by a they are hiding something, lying, or worried about security guard/law enforcement officer. something. The development of centralized networks of CCTV cameras watching public areas—linked to Aerial surveillance computer databases of people's pictures and identity Aerial surveillance is the gathering of surveillance, (biometric data), able to track peoples' movements usually visual imagery or video, from an airborne throughout the city, and identify who they have been vehicle—such as a unmanned aerial vehicle, heli- with—has been argued by some to present a risk to copter, or spy plane. Military surveillance aircraft civil liberties [6]. use a range of sensors (e.g. radar) to monitor the bat- tlefield. Social Network Analysis surveillance Digital imaging technology, miniaturized This type of surveillance involve the creation of computers, and numerous other technological ad- maps of social networks based on data from social vances over the past decade have contributed to networking sites such as Facebook [9,10], MySpace, rapid advances in aerial surveillance hardware such Twitter as well as from traffic analysis information as micro-aerial vehicles, forward-looking infrared, from phone call records such as those in the NSA and high-resolution imagery capable of identifying call database, and others. These social network objects at extremely long distances. "maps" are then data mined to extract useful infor- Some programs have automated much of the
Afr J Med Phy, Biomed Eng & Sc, 2010, 2, 118 - 126 121 aerial surveillance process. An example is the Het- Corporate Surveillance erogenous Aerial Reconnaissance Team program Corporate surveillance is the monitoring of a person developed by DARPA. They have developed sys- or group's behavior by a corporation. The data col- tems consisting of large teams drone planes that pi- lected is most often used for marketing purposes or lot themselves, automatically decide who is sold to other corporations, but is also regularly "suspicious" and how to go about monitoring them, shared with government agencies. It can be used as a coordinate their activities with other drones nearby, form of business intelligence, which enables the cor- and notify human operators if something suspicious poration to better tailor their products and/or ser- is occurring. vices to be desirable by their customers. The data can also be sold to other corporations, so that they Data mining & profiling surveillance can use it for the aforementioned purpose. Alterna- Data mining is the application of statistical tech- tively, it can be used for direct marketing purposes, niques and programmatic algorithms to discover pre- such as the targeted advertisements on Google and viously unnoticed relationships within the data.. Yahoo, where ads are targeted to the user of the Data profiling in this context is the process of as- search engine by analyzing their search history and sembling information about a particular individual emails, especially if they use free webmail services, or group in order to generate a profile — that is, a which is kept in a database. picture of their patterns and behavior. Data profiling can be an extremely powerful tool for psychological Human operatives and social network analysis. A skilled analyst can Organizations that have enemies who wish to gather discover facts about a person that they might not information about the groups members or activities even be consciously aware of themselves [13]. face the issue of infiltration. In addition to operatives Economic (such as credit card purchases) and infiltrating an organization, the surveilling party may social (such as telephone calls and emails) transac- put pressure on certain members of the target organi- tions in modern society create large amounts of zation to act as informants (i.e. disclose the informa- stored data and records. In the past this data would tion they hold on the organization and its members). be documented in paper records and would leave paper-based records, "paper trail", requiring human RFID & Geolocation Devices intelligence operators to manually dig through. But Radio Frequency Identification (RFID) tagging is today many of these records are electronic, resulting the use of very small electronic devices (called in an "electronic trail". Every use of a bank machine, 'RFID tags') which are applied to or incorporated payment by credit card, use of a phone card, call into a product, animal, or person for the purpose of from home, checked out library book, rented video, identification and tracking using radio waves. The or otherwise complete recorded transaction gener- tags can be read from several meters away. They are ates an electronic record. extremely cheap, costing a few cents a piece, so they Public records—such as birth, court, tax and can be inserted into many types of everyday prod- other records—are increasingly being digitized and ucts without significantly increasing the price, and made available online. In addition, some country can be used to track and identify these objects for a laws make it possible that web traffic and online variety of purposes [14]. purchases are also available for profiling. Electronic record-keeping makes data easily collectable, stor- Global Positioning Systems (GPS) able, and accessible—so that high-volume, efficient In some countries like the U.S.A., police have aggregation and analysis is possible at significantly planted hidden GPS tracking devices in people's ve- lower costs. hicles to monitor their movements, without a war- rant. Several cities in USA are running pilot projects
122 G.O. Onwodi, K.I. Nkuma-Udah and F.B. Osang to require parolees to wear GPS devices to track they become self-policing. Though, this allows the their movements when they get out of prison. State to control the populace without having to re- sort to physical force, which is expensive and other- Surveillance "bugs" wise problematic. Surveillance "bugs" or devices are hidden electronic Numerous civil rights and privacy groups devices which are used to capture, record, and/or oppose surveillance as a violation of people's right to transmit data to a receiving party such as a law en- privacy. There have been several lawsuits by groups forcement agency. The U.S.A. has run numerous or individuals, opposing certain surveillance activi- domestic intelligence, such as COINTELPRO, ties. which have bugged the homes, offices, and vehicles of thousands of citizens, such as political activists, 2.3 Legal Aspects of Surveillance subversives, and criminals. There are many and varied legal issues surrounding surveillance and the interception of electronic com- Postal services surveillance munications, primarily because they arise in differ- As more people use faxes and e-mail the signifi- ent contexts: criminal investigations, corporate es- cance of surveilling the postal system is decreasing, pionage, employer-employee relationships, and the in favor of Internet and telephone surveillance. But intelligence activities of the federal government con- interception of post is still an available option for ducted against foreign countries. Two primary issues law enforcement and intelligence agencies, in certain are paramount here. One, rapid changes in technol- circumstances. ogy can sometimes outpace legislation designed to protect a country’s citizens from unwarranted elec- 2.2 Factors Affecting Surveillance tronic intercepts. Two, in response to the threat of One of the reason surveillance systems tend to be terrorism against a country, the federal government encouraged by some people is the belief that these passed legislation that, in the eyes of some, weak- tools protect society from terrorists and criminals. ened constitutional protections against unwarranted Another common argument is: "If you aren't doing interception of electronic communications [15]. something wrong then you don't have anything to Generally, intelligence-gathering operations fear." Again: "As long as we do what we're told, we in surveillance is divided into two broad categories: have nothing to fear" . Other critics state that while a human and electronic [8]. Human intelligence gath- person might not have anything to hide right now, ering, or HUMINT, involves the use of on-the-scene the government might later implement policies that human operatives who, for example, prepare maps, they do wish to oppose, and that opposition might observe enemy troop movements, steal documents, then be impossible due to mass surveillance enabling recruit others to provide information, or physically the government to identify and remove political eavesdrop on conversations. threats [6,15]. Comparatively, HUMINT is a dangerous un- On the other hand, many people fear that so- dertaking and there is the possibility that the opera- ciety is moving towards a state of mass surveillance tive will be caught, forced to reveal information with severely limited personal, social, political free- about his or her activities and purposes, and even doms, where dissenting individuals or groups will be imprisoned or executed. For this reason, intelligence strategically removed in the scheme of things [7]. agencies whenever possible have come to rely more On the social aspects, some believe that in on electronic intelligence gathering, or ELINT. addition to its obvious function of identifying and In ELINT, spy satellites and high-altitude capturing individuals who are committing undesir- planes, can be used to provide accurate and timely able acts, surveillance also functions to create in information about troop deployments or missile in- everyone a feeling of always being watched, so that stallations, while wiretaps and hidden microphones
Afr J Med Phy, Biomed Eng & Sc, 2010, 2, 118 - 126 123 allow communications to be intercepted without tion and acoustics. TEMPEST is the technology for placing an operative in danger. intercepting the electro-magnetic waves over the air. ELINT is divided into two types: trespassory It simply sni ffs through the waves propagated from and nontrespassory. From the name, trespassory any device, including from the monitor of a com- ELINT requires some sort of trespass; as an exam- puter screen. TEMPEST can capture the signals ple, the target's physical premises can be entered to through the walls of computer screen. install a transmitter or microphone. Non-trespassory TEMPEST technology can reproduce ELINT, in contrast, does not require physical inva- what one is seeing in his monitor or what he is typ- sion of the target premises. Since the end of World ing in his keyboard from a couple of kilometers War II and throughout the Cold War, the intelligence away. It traces all electromagnetic radiation from the community has devised various forms of non- person’s monitor, keyboard, pc memory or even trespassory ELINT, enabling it to intercept informa- hard disk, then reproduces the signals. By using this tion transmitted by satellite, radio, cell phone, and technology it is possible to intrude into a person’s microwave transmissions. computer from a couple of kilometers away, even if While ELINT was and is valuable for gather- it is a computer which is not networked and enables ing foreign intelligence, various country’s legislators the intruder to hack without any connection to the and the public were concerned about its possible victims computer. misuse in conducting criminal investigations. For But modern electronic devices emit all instance in the USA, under Title III of the Omnibus sorts of information that is never intended to be Crime Control and Safe Streets Act of 1968 (the "communicated." They do so in the form of what are "Wire Tap Statute"), trespassory interception of called emanated transient electromagnetic pulses electronic communications in criminal investigations (ETEP) or emanations, which can be received and without a court order was made illegal. In 1986 the reconstructed. A computer screen, for example, dis- Electronic Communications Privacy Act amended plays information in the form of pixels that glow Title III to include non-trespassory interception of e- when they are struck by an electron beam. To keep mail, computer communications, and cell phones the pixels on a computer screen lit, the electron calls. beam fires perhaps 60 times per second. The beam's high-voltage electromagnetic emission can be inter- 3. TEMPEST Technology and Signals cepted and read from as far away as a kilometer us- ing this technology called TEMPEST. 3.1 Tempest as A Surveillance Technology The tempest technique enables the soft- TEMPEST is used to mean emissions from elec- ware on a computer to control the electromagnetic tronic components of electromagnetic radiation in radiation it transmits. This can be used for both at- the form of radio signals. These emissions can be tack and defence [2]. To attack a system, malicious picked up by AM/FM radio receivers within a range code can encode stolen information in the machine's varying from a few dozen to a few hundred metres. resonant frequency emissions and optimize them for Building on these data, it is then possible to recon- some combination of reception range, receiver cost struct the original information [1,16]. Protective and covertness. Here the emanations from a remote measures against such risks consist of placing the location are intercepted and the information that was source of the emissions (central processors, monitors captured then replayed. Closing doors and blinds and cables) in a Faraday cage, or jamming the elec- wouldn't do anything to stop a TEMPEST attack. To tromagnetic emissions. defend a system, a trusted screen driver can display Propagation of TEMPEST emanations or sensitive information using fonts which minimize signals can occur by four basic means: electromag- the energy of these emissions. netic radiation, line conduction, fortuitous conduc-
124 G.O. Onwodi, K.I. Nkuma-Udah and F.B. Osang 3.2 Sources of TEMPEST Signals rier may be a parasitic oscillation generated in the Specifically, the emanations [3,4] for the TEMPEST equipment, i.e., the chopper frequency of a power technology can occur as one of the following: supply, etc. The carrier is usually amplitude or an- • electromagnetic fields set free by elements of the gle-modulated by the basic RED data signal or a sig- plaintext processing equipment or its associated nal related to the basic RED data signal, which is conductors. then radiated into space or coupled into EUT exter- • text-related signals coupled to cipher, power, nal conductors. signal, control or other black lines through (a) common circuit elements such as grounds and Impulsive Emanations power supplies or (b) inductive and capacitive Impulsive emanations are quite common in Equip- coupling. ment under Tests processing digital signal, and are • propagation of sound waves from mechanical or caused by very fast mark-to-space and space-to- electromechanical devices. mark transitions of digital signals. Impulsive emana- The two main sources of TEMPEST sig- tions can be radiated into space or coupled into nals are: Equipment under Test external conductors. 1. Functional Sources . - Functional sources are those designed for the specific purpose of generating elec- Other Types of Emanations tromagnetic energy. Examples are switching transis- Most compromising emanations resemble one of the tors, oscillators. Signal generators, synchronizers, types mentioned thus far. There are, however, other line drivers, and line relays. possible types which are caused by various linear 2. Incidental Sources - Incidental sources are those and nonlinear operations occurring in information- which are not designed for the specific purpose of processing equipment and systems. Such compro- generating electromagnetic energy. Examples are mising emanations cannot easily be categorized. In electromechanical switches and brush-type motors. practice, these emanations often exhibit features which can frequently be related to one of the three 3.3 Types of TEMPEST Signals types discussed. The more common types of compromising emana- tions [3,4] are the following: 4. Protection from TEMPEST Attacks RED Base band Signals The most easily recognized compromising emana- There are three ways to protect computers and de- tion is the RED base band signal in attenuated but vices from TEMPEST attacks [1,4,8]. They are by otherwise unaltered form, since it is essentially iden- use of: tical to the RED base band signal itself. This emana- • TEMPEST testing and selection of appropriate tion can be introduced into electrical conductors devices connected to circuits which have an impedance or a • TEMPEST fonts power source in common with circuits processing • TEMPEST proof walls RED base band signals. It can be introduced into an Among these three protective measures the TEM- escape medium by capacitive or inductive coupling, PEST proof walls are the most effective. and especially by radiation with RED base band sig- nals of higher frequencies or data rates. 4.1 TEMPEST Testing and Selection TEMPEST tests are performed to prove that all or a Modulated Spurious Carriers part of communications or information handling sys- This type of compromising emanation is generated tems which are to process national security informa- as the modulation of a carrier by RED data. The car- tion do, in fact provide emission security. The equip-
Afr J Med Phy, Biomed Eng & Sc, 2010, 2, 118 - 126 125 ment or system tested is called equipment under test software for this. These software will calculate the (EUT). An EUT can be visualized as an input/output power dissipation of the normal fonts and if it is vul- box which receives an input signal and produces an nerable to the TEMPEST attack [4,8], the software output signal (figure 1). will filter that software and show that font in the most convenient way. The filtered text looks rather blurred and unpleasant in this magnified representation, but sur- prisingly, the loss in text quality is almost unnotice- able for the user at the computer screen, as the mag- nified photos in the lower half of figure 4.2 show. The limited focus of the electron beam, the limited resolution of the eye, as well as effects created by the mask and the monitor electronics filter the signal Figure 1: Equipment Under Test
In most cases, only EUT input and/or output conductors carry the intentional RED signals [1,4,8]; all other conductors usually carry signals devoid of classified data. Because of design weak- nesses, poor component quality or location, im- proper wiring layout, and inadequate shielding by the chassis cabinet, some unintentional signals may Figure 2: Tempest Fonts be generated in an EUT and emitted through space or on external conductors. Such unintentional signals anyway. are the object of detection and measurement during The text on the left is displayed with a TEMPEST tests, and of particular interest are those conventional font, while the text on the right has signals which may be similar to the RED signals be- been filtered to remove the top 30% of the horizontal cause they are compromising emanations (CE). frequency spectrum. The graphics in the upper row There are three types of TEMPEST test- show the pixel luminosities, while below there are ing: magnified screen photographs of a 21.5 mm text • Electric radiation tests - performed to detect and area. While the user can see practically no difference measure emanations escaping from an EUT in between the fonts, the filtered text disappears from the form of electric fields the eavesdropping monitor while the normal text can • Magnetic radiation tests - performed to detect be received clearly. and measure emanations escaping from an EUT in the form of Magnetic fields. 4.3 TEMPEST Proof walls • Conduction tests - performed to detect and meas- TEMPEST proof walls are developed for preventing ure emanations escaping from an EUT as voltage TEMPEST attacks. These walls are specially de- and current on conductors interfacing an EUT signed for reflecting the electromagnetic waves back with other equipments and power sources. to the same room itself. Many of the corporate firms have the TEMPEST proof walls for protecting the 4.2 TEMPEST Fonts databases from the hackers and spies, otherwise the TEMPEST fonts are used for protecting the com- secret data will be leaked and the eavesdropper will puters from the eavesdropper. There is some specific cause threat to that corporate firm [4].
126 1 G.O. Onwodi, K.I. Nkuma-Udah and F.B. Osang 5. Conclusion [6] Vlahos J., 2008, Surveillance Society: New High-Tech Cameras Are Watching You, Popular The interception of communication is the main func- Mechanics . Available at tion of intelligence agencies all over the world.