Privacy and usability in SMS-based G2B/B2G m-Government: STK and SMS: Balancing privacy and usability

The provision of sensitive information over SMS has been held back due to the inherent privacy problems of SMS. Sending messages as plain-text carries multiple risks. SMS encryption is one solution to this problem. However software written for specific devices might affect the User Experience (UX) while impacting existing investments. Also, using the phone's memory as a data store provides no guarantees against intrusion attacks. A standards-based STK (SIM Toolkit) application has been adopted in order to strike a balance between usability and mobility. An 8-bit microcontroller was used as the main platform for this security application, implementing Twofish symmetric encryption to enhance privacy and confidentiality. Creating synergy between Security and Usability is a challenge, and this paper discusses the role of STK and SMS in G2B m-Government.