Improvement of nuclear facilities DNP3 protocol data transmission security using super encryption BRC4 in SCADA...

Area of Science:

• Cybersecurity
• Information Technology
• Applied Cryptography

Background:

• Supervisory Control and Data Acquisition (SCADA) systems using the DNP3 protocol are vulnerable to man-in-the-middle (MITM) attacks.
• These attacks can lead to data interruption, interception, fabrication, and modification, compromising system integrity.
• Existing security measures may not fully address the specific threats posed to DNP3 communications.

Purpose of the Study:

• To enhance the security of DNP3 data transmissions within SCADA systems.
• To develop a novel encryption method that protects against man-in-the-middle (MITM) attacks.
• To improve the efficiency of key generation processes in secure data transmission.

Main Methods:

• A new encryption method, BRC4, is proposed, combining Beaufort encryption with RC4 stream cipher.
• Beaufort encryption utilizes a poly-alphabetic substitution based on the Beaufort table and plaintext subtraction.
• RC4 encryption provides a stream cipher with a variable-length key algorithm for enhanced security.

Main Results:

• Key space analysis indicates a minimum key length of 16 characters is necessary for brute-force attack resistance.
• Information entropy values (IL1=7.84, IL2=7.98, IL3=7.99) and low data correlation (IL1=-0.010, IL2=0.006, IL3=0.001) demonstrate BRC4's superiority over isolated Beaufort or RC4.
• Visual analysis confirms ciphertext distribution security, and time complexity analysis classifies the algorithm as linear.

Conclusions:

• The proposed BRC4 encryption method significantly enhances DNP3 security against MITM attacks.
• BRC4 offers superior cryptographic properties compared to standalone Beaufort or RC4 encryption.
• The method is efficient, with linear time complexity and improved key generation speed, making it suitable for SCADA systems.