Project Summary: 

The use of access control and cryptography is becoming more prevalent, especially since the introduction of GDPR regulations in May 2018. However, often there is a requirement that we may need to search on encrypted documents or grant access to a subset of encrypted files, subject to the user’s identity, for example rank in an organisation or security clearance level.  Functional cryptography is a type of cryptography that includes exciting extensions to the functionality of traditional cryptographic schemes, to provide fine-grained access control and simplify key management processes.  Examples include identity-based encryption (IBE), attribute-based encryption (ABE) and attribute-based signatures (ABS)

Moreover, with rapid developments being made towards the creation of quantum computers, the security of our existing public key cryptography is threatened, as a working quantum computer would render our existing public key cryptography insecure.  Thus,cryptographers are currently developing quantum resistant (or post-quantum) cryptosystems, as public key cryptography replacements.

Traditional IBE and ABE schemes rely on pairing based cryptography, which has been used in cryptography since the 1990’s. Recent theoretical advancements include the introduction of lattice-based IBE and ABE, which provide quantum resistance for long term security provisioning, and preparing for future advancements in quantum computing.  Such quantum resistant schemes are in demand and require further investigation, especially from a practical point of view.  Particularly, the feasibility of lattice-based IBE and ABE on lightweight devices is of interest, particularly for IoT applications.

Advanced applications, such as attribute-based signatures (ABS), are of particular interest to allow fine-grained control over signing a message.  Attribute-based signatures enable advanced functionality, and offer limited information of the signer, thus providing anonymity, for example one can ensure the person signing a message is over 18, without revealing the exact age of the person.  Other applications include anonymous authentication and attribute-based messaging.


The objectives of this research are:

  • To study the state of the art in functional cryptography, particularly ABE and ABS
  • To analyse quantum resistant variants of ABE and attribute-based signatures in terms of practicality
  • To investigate the practicality of attribute-based signatures, using novel algorithmic and architectural optimisations
  • To investigate hardware implementations of attribute-based signatures, targeting the FPGA platform


This PhD will be carried out in collaboration with Thales, who will support a placement for the successful candidate.


Academic Requirements:

Students entering the programme will normally be required to have a 2.1 BSc/BEng in Computer Science, Electrical and Electronic Engineering, or a maths based engineering or physical science degree, or equivalent qualification recognised by the University. Students holding an appropriate MEng or MSc (Software conversion) will normally be required to have a 2.1 or commendation (distinction) respectively. Furthermore, additional criteria may be applied. All applicants must have significant mathematical and programming experience.

General Information

This 4 year PhD studentship, potentially funded by the Department for Employment and Learning (DEL), commences on 1 October 2019.

Eligibility for both fees and maintenance depends on the applicants being either an ordinary UK resident or those EU residents who have lived permanently in the UK for the 3 years immediately preceding the start of the studentship. Non UK residents who hold EU residency may also apply but if successful may receive fees only.

Applicants should apply electronically through the Queen’s online application portal at:

Further information available at:


Contact Details:

Supervisor Name: Dr Ciara Rafferty                                              

Tel: +44 (0)28 9097