Producing a configuration requires going through a number of steps and decisions, where the order in which those steps are performed can effect both the quality of the final solution and the efficiency of reaching that solution. To date, it has not been possible to construct an ordering for those steps that is best for a sufficiently high number of cases. DESSERT has developed a support tool called the Task Orderer for use in the GSAC decision support system.
The Task Orderer provides decision support to the user by continually monitoring the progress towards problem solution, advising the user of which tasks could be carried out next and recommending which of those tasks should be addressed. The user can then select which task to perform based on the Task Orderer's recommendations.
The Task Orderer has been implemented by extending an agenda-based control mechanism taken from a blackboard. In a traditional blackboard system, whenever a tool can perform some work it informs a blackboard controller which obeys some strategy in determining which of the tools that can be used should be used. In GSAC this has been extended so that when tools can perform some work they inform the Task Orderer, which then supports the user in deciding which tool to run next. The Task Orderer continuously monitors the reports coming from each tool and the tools in turn continually monitor what they can contribute to a problem solution. As a result the user is offered active support to decide what task should be performed next.
The user interface to the Task Orderer is divided into five regions (see Figure 1).
A the current toolset button panel which displays those tools that are available in the GSAC DSS. If a tool's button is greyed out then there is no problem for that tool to work on.
B the list of possible next tasks to perform region which lists those tasks that the currently selected tool can perform. This list is ordered
C a list of current running tasks region which lists those tasks that the currently selected tool is performing.
D a graphical display of requirements network window which gives a pictorial representation of the current state of the problem/solution network. This displays the entities (i.e. customer sites, service and network resources) involved in the current set of requirements, and the communication requirements between them. The entities are represented by nodes with edges representing the communication requirements. The status of progress towards a global solution is indicated by colouration of the arcs. Also, the thickness of the arcs indicates the amount of requirements placed on this link.
E a message area outputs messages as feedback to user initiated commands.
Figure 1: Example Task Orderer Window
"Decision Support for Configuring Telecommunication Services", R. Davison, P. O'Brien, D. O'Sullivan, Information and Decision Technologies 19, North Holland, (1994).
"The blackboard model of problem solving and the evolution of blackboard architectures", H.P. Nii. Blackboard systems (part one), The AI Magazine, pp 38-53, (Summer 1986).
