Code Verification. Intuitively, an attacker on a smart-card-based password authentication protocol should be unable to make a successful log-in only with the smart card (or the password), or compromise other additional properties (e.g., key agreement). To capture these requirements, we define the potential attacker from two aspects, namely the behavior of the attacker and the information compromised by the attacker. As an interactive protocol, a smart-card-based password authentication protocol may be faced with a passive attacker and an active attacker a passive attacker can obtain messages transmitted between users and the server. This is due to the fact that communication channels are generally insecure, and the attacker can observe messages by eavesdropping. A passive attacker cannot interact with any of the parties in smart- card-based password authentication protocols. Xxxxx & Xx Xxxxxx Xxxxx et al scheme Xxx et al scheme Xxxxx et al scheme Juang scheme Implementation low communication and computation cost X A A A A A no time- synchronization problem X A X X A A utual authentication X A A A A A identity protection X A X X X A preventing offline dictionary attack X X X X X A
Code Verification. Code verification ensures that the computer program is a faithful representation of the original mathematical model. In figure 2 above, we showed that errors can be introduced when implementing the conceptual models on a computer, via coding mistakes. Practitioners cannot fix errors in coding but by they need to understand the processes involved in this stage of verification.
Code Verification. Code verification ensures that the computer program is a faithful representation of the original mathematical model. Errors can be introduced when implementing the conceptual models on a computer, via coding mistakes. Code verification procedures include: • Software engineering: monitoring and controlling the software development processes and software products to ensure reliability. A formal quality procedure such as ISO 9001 is a positive indicator; publication of a comprehensive set of verification tests is recommended. • Invariance tests: checking for consistency of outputs following simple operations such as translating or rotating the domain, mirroring the domain. • Conservation tests – ensuring that mass and/or energy are conserved. • Formal order of accuracy assessment. This examines whether the discretization error reduces at the theoretical rate expected as the mesh and/or time step are refined. Achieved via a grid refinement study and comparison of error norms for each result.
