Task Modelling for a Holistic Quality of Service Model - TRAQS

This paper focuses on task modelling of a Three Layer Quality of Service (QoS) model (TRAQS). The TRAQS model comprises of three perspective layers, namely: User Perspective Layer (UPL), Application Perspective Layer (APL) and Transmission Perspective Layer (TPL), for the provision and negotiation of QoS in multimedia communications. We provide a review of current QoS protocols and architectures and identify that in these models the provision and negotiation of QoS is administered mainly in the Application and/or Transmission Perspective Layers. We present a taxonomy for classifying applications and QoS parameters, modelled as a QoS Parameter Architecture (QPA). Our classification of parameters is given in a QoS Parameter Taxonomy and an Application Taxonomy. We provide a summary of our previously developed Quality Cost & Temporal Triangle, Application Classification Model, and Application Profile model. We expatiate our research to the next level by investigating the requirements and operations of the TRAQS model operating in a distributed environment. We provide a TRAQS communication model identifying the five stages of QoS provision, and model it using formal Task Modelling techniques. We identify the functional requirements and represent it as a taxonomy of tasks and sub-tasks in a task modelling tool called Concur Task Tree Environment (CTTE). Finally, we provide an overview of the next step to be taken and the future direction of this research.