TEMPEST is a codename for a set of standards and studies developed primarily by the U.S. and NATO to prevent the leakage of information through unintentional electromagnetic emanations from electronic devices. This includes emissions from displays, keyboards, CPUs, power supplies, and cables.
The goal of a TEMPEST engineer is to ensure that sensitive information processed in electronic systems is not leaked via unintended RF signals or other emissions that adversaries could exploit.
Learning Outcomes:
- Understand the history and purpose of TEMPEST.
- Identify types of compromising emanations.
- Explain the risk posed by unshielded or poorly shielded equipment.
Principles of Electromagnetic Emissions
All electronic devices emit electromagnetic energy. When these emissions correlate with the data being processed, they become potential vulnerabilities. TEMPEST engineers must understand the physics behind these emissions.
Topics:
- Electromagnetic spectrum basics
- Conducted vs. radiated emissions
- Near field vs. far field emissions
- Correlation between signal processing and emission patterns
Example: CRT monitors emit signals that can be intercepted and reconstructed into readable screen images from distances up to several hundred meters without direct access to the system.
Eavesdropping Techniques
Adversaries use various techniques to capture emissions, even from devices that aren’t network-connected.
Common Techniques:
- Van Eck phreaking (monitor emissions)
- RF sniffing (keyboard and CPU emissions)
- Laser microphone attacks (vibrations induced by sound in objects)
- Conducted emissions via power lines and grounding paths
As a student, you would study the hardware and signal processing tools used to capture, filter, and analyze these emissions.
Threat Modeling and Risk Assessment
A key skill for TEMPEST engineers is identifying which assets are vulnerable and what the actual risk level is.
Topics:
- Categorizing zones (e.g., Zone 0, Zone 1, Zone 2 – based on proximity and threat level)
- Assessing signal strength vs. adversary capabilities
- Evaluating the attack surface: cables, connectors, monitors, enclosures
- Understanding red/black separation (handling of classified vs. unclassified signal paths
Shielding and Mitigation Techniques
TEMPEST engineers use a combination of physical and electronic countermeasures to reduce risks.
Mitigation Methods:
- Faraday cages: Enclosures that block EM radiation
- Shielded cables and connectors
- Filtering (e.g., power line filters)
- Equipment grounding and bonding
- Signal masking or signal randomization
- Distance and directional placement strategies
Hands-On Lab: Measure emissions from a laptop using a spectrum analyzer, then remeasure after applying different shielding methods.
Standards and Certification
There are formal guidelines and requirements for TEMPEST certification of devices, facilities, and personnel.
Key Standards:
- NSTISSAM TEMPEST/1-92 (U.S.)
- CNSS Instruction No. 7000
- NATO SDIP-27 Levels A, B, and C (based on threat environment)
- NSA/CSS Evaluated Products List
You would study how to apply these standards, how systems are evaluated, and how certification testing is performed.
Facility Design
Beyond individual devices, entire rooms or buildings may need to be TEMPEST-secure.
Topics:
- Secure room construction
- RF attenuation material selection
- Shielded enclosures and waveguides
- TEMPEST zoning inside facilities
- HVAC and power considerations
Project: Design a secure communications room that meets SDIP-27 Level A requirements
Equipment Testing and Analysis
To be a competent TEMPEST engineer, one must understand how to measure emissions and validate system security.
Tools:
- Spectrum analyzers
- Oscilloscopes
- RF sniffers and antennas
- Anechoic chambers
- Line impedance stabilization networks (LISNs)
Activities:
- Identify emissions from test devices
- Evaluate shield effectiveness
- Analyze spectrum data and determine risk
Emerging Threats and Modern Devices
As technology evolves, so do threats.
Topics:
- Emanations from IoT and wireless devices
- Optical side channels (e.g., LEDs)
- Acoustic side channels (e.g., keystroke sounds)
- Electromagnetic attacks against air-gapped systems
You would explore new frontiers in side-channel analysis and how modern systems increase or reduce risk exposure.
Ethical and Legal Considerations
Because TEMPEST work deals with national security and classified information, ethical conduct and legal compliance are critical.
Topics:
- Classified handling procedures
- Insider threat awareness
- Legal boundaries of signal interception
- Contractor and government roles in TEMPEST enforcement
Final Thoughts
Becoming a TEMPEST engineer means mastering both theoretical knowledge and applied skills in electromagnetic emissions, shielding, threat modeling, and standards compliance. It’s a multidisciplinary field touching electrical engineering, physics, information security, and military standards.
Tonex offers Certified Tempest Engineer Training, a 2-day course where participants master the foundational concepts of TEMPEST and its importance in safeguarding electronic systems as well as acquire proficiency in TEMPEST testing techniques, including measurement methodologies and data analysis.
Attendees also develop expertise in the design and implementation of TEMPEST countermeasures for various electronic devices, learn the regulatory frameworks governing TEMPEST standards and compliance, gain hands-on experience in conducting TEMPEST assessments and effectively mitigating electromagnetic vulnerabilities, and obtain the certification and skills necessary to excel as a Certified TEMPEST Engineer.
This training is tailored for professionals involved in the design, development, testing, and implementation of electronic systems, as well as individuals responsible for ensuring the security of sensitive information in government, defense, and critical infrastructure sectors. It is ideal for engineers, security professionals, and project managers seeking to enhance their expertise in TEMPEST.
All told, Tonex offers over 30 courses in its Radiation Resilience Institute. Sample courses include:
Certified Critical Infrastructure Protection Engineer Training
Certified Emission Security (EMSEC) Technician Training
Certified SCIF/SAPF Planner (CSSP) Certification Program
RF Shielded Enclosure Design Engineer (RFSEDE) Certification Program
Certified ICD-705 Project Manager (CICD-705-PM) Certification Program
For more information, questions, comments, contact us.