Quality of Service in Distributed Object Systems

Abstract

The suitability of the object-oriented programming model for implementing distributed systems has lead to middleware platforms, such as CORBA, DCOM, and Java/RMI. Originally, these middleware systems aimed at distribution transparency for application programmers. However, distributed systems are exposed to system issues, such as dynamic performance changes or partial errors, which prevent complete distribution transparency. Quality of Service (QoS) management addresses these system issues. The goal is to add QoS management to the interactions between clients and services. Support for QoS management in distributed object systems is a hot topic of current research which poses a number of open questions: How is QoS integrated with the object model that emphasizes encapsulation and information hiding? Can one build generic support frameworks for multiple QoS categories, in contrast to specialized, single category systems, such as TAO, Electra, Eternal, DOORS among others. Can QoS be viewed as an aspect in the sense of Aspect Oriented Programming (AOP) or are other classifications more appropriate? This ECOOP-workshop has discussed the open questions and aimed at a summary of the state of the art in the field. The workshop stimulated discussions about how next generation QoS management facilities can be built into object infrastructures.