1.2 Summarize fundamental security concepts
📘CompTIA Security+ SY0-701
🧩 What is Physical Security?
Physical security refers to the protection of the physical environment — such as buildings, rooms, servers, and network equipment — from unauthorized physical access, theft, damage, or disruption.
While cybersecurity focuses on data and systems, physical security focuses on protecting the hardware and infrastructure that store and process that data.
Goal: Prevent physical threats (like intruders, tampering, or sabotage) that can lead to loss of confidentiality, integrity, or availability of systems.
🧱 Layers of Physical Security
Physical security uses a layered defense approach — multiple security measures are combined to protect different areas:
- Outer perimeter: Protects the area around the facility (fences, gates, bollards).
- Building perimeter: Controls access into the building (guards, access doors, badges).
- Internal areas: Protects sensitive rooms (server rooms, data centers).
- Internal equipment: Protects actual devices (racks, sensors, locks).
🏗️ Common Physical Security Controls
Let’s go through each control one by one.
1. Bollards
Definition:
Short, strong vertical posts installed around entry points or buildings to prevent vehicles from approaching too close.
Purpose:
- Protects the building and data center entrances from vehicle-based attacks or crashes.
- Prevents someone from using a vehicle to break into a secure facility or damage network hardware (e.g., generator, data center wall).
Exam Tip:
Bollards are considered a physical barrier control used for perimeter defense.
2. Access Vestibules (Mantraps)
Definition:
An access vestibule (also called a mantrap) is a small room with two interlocking doors — only one door opens at a time.
Purpose:
- Controls who enters secure areas like server rooms or data centers.
- Prevents tailgating (someone following an authorized person inside).
- Used to verify identity before granting full access.
Example in IT environment:
When entering a data center, a person swipes their badge to enter the vestibule. Once the system confirms their credentials, the inner door unlocks to the server room.
Exam Tip:
Mantraps = “Two-door system” to control and verify identity before entry.
3. Fences
Definition:
Physical barriers placed around the outer perimeter of a building or property.
Purpose:
- Clearly defines boundaries of restricted areas.
- Prevents unauthorized people from entering the facility.
- Can work with gates and access control systems.
Exam Tip:
Fences are deterrent and preventive physical controls.
4. Video Surveillance (CCTV – Closed-Circuit Television)
Definition:
A system of cameras used to monitor and record activities in and around the facility.
Purpose:
- Helps in detecting suspicious activity and identifying intruders.
- Used to review incidents such as unauthorized entry or data theft.
- Can integrate with motion sensors or access control systems.
Types:
- Analog cameras: Basic video feed stored on DVR.
- IP cameras: Digital, network-connected cameras with remote monitoring and storage.
Exam Tip:
Video surveillance = detective control (used to detect and record activity).
5. Guards (Security Personnel)
Definition:
Trained human security staff responsible for monitoring and enforcing physical access control policies.
Purpose:
- Verify identity of people entering restricted areas.
- Respond to alarms or incidents.
- Monitor CCTV feeds and patrol the area.
In IT environments:
Guards control access to data centers, check ID badges, and ensure only authorized IT staff enter.
Exam Tip:
Guards provide both deterrent (visible presence) and preventive control.
6. Access Badges
Definition:
Identification cards (often electronic) that allow authorized personnel to access restricted areas.
Purpose:
- Each badge contains a unique identifier linked to a person’s credentials.
- Works with card readers or biometric scanners to unlock doors.
- Can record who accessed what area and when, useful for auditing.
Types:
- Magnetic stripe cards
- Proximity (RFID) cards
- Smart cards
Exam Tip:
Access badges are part of an access control system used for authentication and logging.
7. Lighting
Definition:
Proper illumination around and within a facility to enhance visibility.
Purpose:
- Deters intruders by eliminating dark hiding spots.
- Helps security cameras capture clearer footage.
- Increases safety for authorized personnel.
Placement:
- Around entry points, parking areas, and building perimeters.
Exam Tip:
Lighting = deterrent control — discourages unauthorized access.
8. Sensors
Sensors are used to detect movement, presence, or activity in restricted areas.
Different sensor types use various technologies to detect intrusions.
Let’s go through each type:
a) IR (Infrared) Sensors
- Detect changes in heat (body heat) or infrared radiation in an area.
- Trigger an alarm when a heat source moves where it shouldn’t be.
- Commonly used in server rooms or restricted corridors.
Exam Tip: IR sensors detect heat movement — a type of motion detector.
b) Pressure Sensors
- Detect pressure or weight on a surface (like floor panels or mats).
- Used to monitor if someone steps into a restricted area or onto a protected floor.
Exam Tip: Pressure sensors detect physical presence in secure zones.
c) Microwave Sensors
- Emit microwave signals and detect movement by changes in the reflected waves.
- Can cover a large area and even detect motion through walls.
Exam Tip: Used for motion detection in high-security environments.
d) Ultrasonic Sensors
- Use sound waves (ultrasound) to detect movement by measuring sound reflections.
- Often used indoors for detecting motion in hallways or rooms.
Exam Tip: Ultrasonic = detects motion via sound reflections.
🧠 Summary Table
| Physical Control | Purpose / Function | Type of Control |
|---|---|---|
| Bollards | Prevent vehicle intrusion | Preventive |
| Access Vestibule (Mantrap) | Control and verify entry | Preventive |
| Fences | Define and secure perimeter | Preventive / Deterrent |
| Video Surveillance (CCTV) | Monitor and record activity | Detective |
| Guards | Enforce access control | Preventive / Deterrent |
| Access Badges | Authenticate authorized users | Preventive |
| Lighting | Deter and illuminate | Deterrent |
| IR Sensors | Detect heat-based movement | Detective |
| Pressure Sensors | Detect physical presence | Detective |
| Microwave Sensors | Detect motion via wave reflection | Detective |
| Ultrasonic Sensors | Detect motion via sound waves | Detective |
🧾 Key Exam Pointers
- Physical controls protect hardware, facilities, and personnel — not data directly.
- Know which controls are preventive, deterrent, or detective.
- Video surveillance and sensors are detective controls.
- Lighting, fences, and guards often serve as deterrent controls.
- Bollards and mantraps are preventive physical controls used for access restriction.
✅ In Short
Physical security ensures that no one can physically access, steal, or damage the systems and devices that store sensitive data.
It’s the first line of defense before digital security measures like firewalls and encryption come into play.
