A Graphical User Interface Reference Model for Messaging Systems with Directory Integration

  • Renato Iannella

Student thesis: Doctoral Thesis


Electronic mail is undoubtedly one of the most successful computer applications in the Information Technology industry. International standards, such as the X.400 Message Handling Systems, have been developed to enable the continual expansion of electronic mail services to a wide range of users. The X.400 standard has comprehensively detailed the functional level of message handling systems but, as with all CCITT standards, has stopped short of defining any requirements for the user interface.
This thesis presents a reference model for the design of graphical user interfaces for X.400 compliant user agents. The reference model was developed from an prototypical implementation of an X.400 user agent called ‘Iris’. The Iris reference model was the result of a comprehensive usability study of the graphical user interface for the Iris user agent.
The X.400 issues focused upon in the Iris reference model include the complexity of specifying message recipient addresses and management of a large number of message options. The graphical user interface issues include large list management and forms-based screen design.
One of the most promising international standards is the X.500 Directory Services. X.500 provides a global distributed database of information on people and an extensible range of other objects. The directory enables users to store their complex X.400 addresses and provides a more consistent and reliable method to access this information. The reference model also describes the requirements for the integration of X.500 Directory Services with X.400 Message Handling Systems. This tightly coupled integration is considered to be a powerful enabling technology for electronic mail users.
The Iris reference model provides the computing science discipline with a proven and functional specification for graphical user interfaces to X.400 user agents with X.500 directory support. The processes in developing the model were based on sound design principles backed up by extensive usability trials.
Date of Award4 Jun 1994
Original languageEnglish
SupervisorMichael Rees (Supervisor)

Cite this