Assignment 3 – Formal System Specification
Overview
The purpose of this assessment is to provide students with the opportunity to apply knowledge and
skills developed during the semester with particular reference to the formal specification of a system
through the use of Z notation.
In this assignment, you will use the Z specification language to provide the sets, relations and
functions in schemas to specify a subsystem relating to the theme of the smart campus. You can
choose the subsystem based on previous work has already completed. Your schemas should provide
the stored data that the system accesses and alters and identify the operations that are applied to
change the state as well as the relationships that occur within the system. Remember, as specified in
Spivey’s 2001 text, The Z Notation: A Reference Manual, schemas are utilized to illustrate both static
and dynamic aspects of a system. Static aspects include such things as the states a system occupies
and the invariant relationships that continue to exist as the system moves between states. Dynamic
aspects include the changes of state that occur, possible operations and the relationships between
their inputs and outputs. Remember also you should always be conscious of the fact that a
specification tries to describe what the system must do without saying how it is to be done (Spivey,
2001).
Assessable Tasks/Requirements
You are to provide brief written description of your requirements and create a set of Z schemas that
adequately describes the subsystem formally. It should include at least one state space and You
must individually write at least two operations and should also write an initialization operation
called Init. You should provide robust versions of each operation that are capable of handling any
possible error conditions. You should also add a narrative to explain any schemas or logic that you
have used. Authorship should be made clear. You might be asked to explain and answer questions
about your work.
Additional Information
General Comments
The submission must be presented in a professional, clear and concise manner. If you need further
system information please use your initiative and make reasonable and logical assumptions.
Questions of a general nature (for example to clarify some part of the assignment requirements) can
also be sent to the discussion forum but these should not in any way provide solutions or parts
thereof.
Reading
– Introduction to Z Notation – http://www.youtube.com/watch?v=qfEe9luJmVE
– The Z Notation: A Reference Manual (Spivey, 2001)
– Weeks 4 and 5 study materials and Section 4 of study guide three