MEASURING AND OPTIMIZING CORBA LATENCY AND SCALABILITY OVER HIGH-SPEED NETWORKS

There is increasing demand to extend object-oriented middleware, such as OMG CORBA, to support applications with stringent quality of servic e (QoS) requirements. However, conventional CORBA Object Request Broke r (ORB) implementations incur high latency and low scalability when us ed for performance-sensitive applications. These inefficiencies discou rage developers from using CORBA for mission/life-critical application s such as real-time avionics, telecom call processing, and medical ima ging. This paper provides two contributions to the research on CORBA p erformance. First, we systematically analyze the latency and scalabili ty of two widely used CORBA ORBs, VisiBroker and Orbix. These results reveal key sources of overhead in conventional ORBs. Second, we descri be techniques used to improve latency and scalability in TAO, which is a high-performance, real-time implementation of CORBA. Although conve ntional ORBs do not yet provide adequate QoS guarantees to application s, our research results indicate ii is possible to implement ORBs that can support high-performance, real-time applications.