Date on Master's Thesis/Doctoral Dissertation


Document Type

Doctoral Dissertation

Degree Name

Ph. D.


Computer Engineering and Computer Science

Committee Chair

Graham, James H.

Author's Keywords

Network security; SSL; N-Secrecy; SCADA; Double security; Authentication


Computer networks--Security measures; Cryptography--Mathematics; Cryptography--Data processing


Due to the overwhelming increase in open source code, off-the-shelf software packages, third party and vendor codes, along with the ease of getting information about hacking network security systems and attacking the well known holes in security systems, the problem of having a secure network system is much more difficult than before this boom in technology and information broadcast. What makes the problem even worse is trying to secure a network for real time control, such as a network using supervisory control and data acquisition (SCADA) systems, because now the problem has two faces: securing the real time control system and at the same time keeping the response time of the system in the acceptable range for the transactions' level of service. There is a strong trend to chose security frameworks that have been popular in the e-commerce sites of the web, particularly because they proven to be very mature and secure for more than one and half decades. Examples include the transport level security (TLS) and its predecessor secured socket layer (SSL) framework that is based on the very popular public key cryptography and key distribution algorithms, such as Rivest, Shamir and Adleman (RSA), elliptic curve cryptography (ECC), and Diffie-Hellman. Despite the fact that these algorithms proved to be very powerful against most types of attacks, they are not tailored to secure SCADA networks, and consequently cause a significant degradation in the performance time of real time transactions. This dissertation offers two novel encryption algorithms for securing a SCADA network, the N-Secrecy and the Security Spectrum algorithms. N-Secrecy gave very good results when compared with the SSL; with N-Secrecy performance time in the range of one thousandth of the SSL. The Security Spectrum approach moved the encryption methodology from using numerical representations into using a physical representation based on modeling the conditions of the two communicating parties with a system of non-linear polynomials and then using computer algebra techniques. Both approaches have the potential to significantly enhance the security of commercial SCADA installations.