4.1 Explain the importance of basic network security concepts
Physical Security
📘CompTIA Network+ (N10-009)
Why Locks Matter in Network Security
Locks help protect:
- Server rooms
- Network closets
- Racks holding switches, routers, and firewalls
- Data centers
- Storage areas for backup drives and sensitive documents
Locks ensure that only authorized personnel can physically touch or remove equipment. Without proper locking mechanisms, attackers could:
- Disconnect devices
- Install malicious hardware
- Steal storage drives and access data
- Reset devices to factory settings
- Bypass digital authentication by accessing physical ports
For the exam, remember:
Physical access almost always equals full control.
This is why locks are essential.
Types of Locks Used in IT Environments
1. Mechanical Locks
These are traditional physical locks that use keys made of metal.
a. Keyed Locks
- Most common type of lock used in IT rooms and cabinets
- Requires a physical key
- Used for server room doors, storage cabinets, and network racks
Advantages:
- Simple and low cost
- No electronics required
Disadvantages:
- Keys can be lost, duplicated, or stolen
- If one key is compromised, you may need to replace all associated locks
b. Padlocks
- Used to secure cages, outdoor network equipment, or backup storage boxes
- May be keyed or combination-type
Exam Tip:
Know that padlocks are portable and used for temporary or flexible security needs.
2. Combination Locks
These locks require a numerical code instead of a physical key.
a. Mechanical Combination Locks
- Use a dial or numeric push-buttons
- Good for securing server room doors or equipment cages
Advantages:
- No key to lose
- Easy to change the combination
Disadvantages:
- Codes can be shared too widely
- Wear on the buttons may reveal commonly used numbers
Exam focus: Combination locks are good for basic access control but weaker than electronic locks.
3. Electronic Locks
Electronic locks are commonly used in modern IT facilities.
a. Keypad Locks
- Users enter a PIN to unlock
- Used for server room doors or restricted areas
Advantages:
- Easy to change PINs
- Can assign different PINs to different people
- Logs can track who entered and when (depending on system)
b. Card-Based Locks
Also known as proximity locks or badge readers.
- Require an ID badge or smart card
- Unlock when the card is tapped or swiped
- Widely used in corporate buildings and data centers
Advantages:
- Logs access attempts
- Can quickly disable a lost or stolen card
- Supports least-privilege access
c. Electronic Key Fobs
- Small devices used to unlock doors wirelessly
- Work similarly to card readers but with active radio signaling
d. Biometric Locks
Use biological traits for authentication:
- Fingerprint
- Face recognition
- Iris scanning
Biometric locks are used for highly sensitive IT areas.
Advantages:
- Cannot be forgotten or shared
- Strongest form of physical personal identification
Disadvantages:
- More expensive
- Requires maintenance and calibration
Exam Tip:
Biometrics provide the highest level of assurance for physical access control.
4. Smart Locks
- Connect to a network for remote monitoring and management
- Can integrate with security systems like cameras, alarms, and access logs
- Often used in modern data centers
Capabilities include:
- Remote unlocking
- Real-time monitoring of door status
- Activity logging
- Automated locking schedules
5. Cabinet and Rack Locks
Even if the server room is secure, IT racks also need protection.
a. Rack-Mounted Locks
- Installed on server racks holding switches, routers, and servers
- Prevent unauthorized access to front/back panels
b. Cage Locks
- Used for locking individual servers or equipment inside a rack
- Helps secure sensitive hardware even if someone is inside the server room
Locking Considerations for IT Environments
1. Access Control and Authorization
Locks should enforce:
- Role-based access (only authorized personnel)
- Least privilege access (minimum access needed to do the job)
2. Logging and Monitoring
Electronic and smart locks can:
- Record entry times
- Track failed access attempts
- Integrate with SIEM/logging tools
This is useful for audits and incident investigations.
3. Lock Maintenance
- Change mechanical locks if keys are lost
- Update codes regularly
- Monitor electronic lock batteries
- Review access lists for former employees
4. Two-Factor Physical Access
High-security areas may use multiple layers such as:
- Card swipe + PIN
- Biometric + door lock
- Entry door + inner cage lock
This is known as defense in depth.
What to Remember for the Network+ Exam
You should understand:
✔ Locks are important for preventing unauthorized physical access
✔ Types of locks: mechanical, combination, electronic, biometric, smart
✔ Card readers and biometrics provide stronger access control
✔ Rack locks protect switches, routers, and servers
✔ Logs from electronic locks assist with auditing
✔ Physical security supports overall cybersecurity
Key Concept:
If an attacker gains physical access, they can often bypass network security controls. Locks help prevent this.
