Background Leonie is a Senior Lecturer in the School of Electrical Engineering and Computer Science. Leonie is a cryptographer whose research focusses on symmetric cryptography. Her doctoral thesis (QUT, 2000) examined design and analysis of certain types of stream ciphers, and she retains a strong interest in stream ciphers, but has broadened her research scope to symmetric ciphers, and modes of operation of ciphers. Leonie has a strong interest in the broader field of information security, where cryptography is applied to secure information. She is particularly interested in cryptographic algorithms suitable for implementation in small devices. These will be useful in improving IoT security.
Current research areas:

• Authenticated encryption

Investigation of methods for providing both confidentiality and authentication of messages in a very efficient manner. For many applications, processing to provide security services needs to be fast, as the transmission is in real time (for example, mobile phone communications). However, small devices impose constraints in terms of the implementation footprint and memory and power availability.

• Initialisation of stream ciphers

Stream Ciphers are often used for frame-based communications. Examples include mobile phone communications and internet transmissions. The same secret key is used with different known initial vectors (for example, frame number) to produce different initial states, and hence different keystreams. The process of forming different initial states from the same secret information requires careful consideration to avoid revealing the secret key.