Date of Award


Document Type

Thesis (Undergraduate)


Department of Computer Science

First Advisor

Sean Smith


This thesis proposes a key management protocol for secure power SCADA systems that seeks to take advantage of the full security capacity of a given network by allowing devices to use public key cryptography for key management if they are capable of doing so and reverting to symmetric key cryptography only when such use is necessitated by the weakness of a given device. Allowing devices to obtain different levels of security permits SCADA networks to maximize their security in the decades before such networks are capable of implementing fully public key-based key management protocols. Such a system is obtained through the use of a protocol based on a modified version of SSL using X.509 certificates containing encrypted symmetric keys that allow master devices the option of using the symmetric keys for encrypting the shared secret used to create keying material, instead of using a slave device's public key. This thesis presents the protocol and uses proof-of-concept code to carry out a performance evaluation of the key management scheme.


Originally posted in the Dartmouth College Computer Science Technical Report Series, number TR2008-628.