POSTECH DPNM Lab POSTECH DPNM Lab Introduction Providing

POSTECH DPNM Lab

POSTECH DPNM Lab Introduction • Providing Quality-of-Service (Qo. S) to users of distributed multimedia services is a difficult problem. • The service user must be given the capabiltiy to express his requirements for the receiving service in terms of Qo. S parameters familiar to him. • It requires a vertically integrated architecture that can deliver end-toend Qo. S guarantees at multiple levels of an entire distributed system. • We present an object-oriented Qo. S management middleware for managing Qo. S of distributed multimedia services and applications. • A key component in this middleware is Qo. S Management Service Object (QMSO), providing multimedia applications with Qo. S management service APIs.

POSTECH DPNM Lab Related Work • Int-serv Architecture – Provides controlled Qo. S for multimedia applications over an integrated services internetwork. • OSI Qo. S Framework – Defines terminology and concepts for Qo. S and provides a model which identifies objects of interest to Qo. S in open system standards • Qo. S-A – Provides a layered architecture of services and mechanisms for quality of service management • Qu. AL – Quality Assurance Language (Qu. AL) for the specification of Qo. S constraints on underlying computing and communication platforms. • Quality of Service for CORBA Objects (Qu. O) – Supports Qo. S at the CORBA layer and extends the CORBA functional Interface Description Language (IDL) with a Qo. S Description Language (QDL)

POSTECH DPNM Lab Qo. S Management Framework Multimedia App. Qo. S Management API QMSO Qo. S MIB QMSO Qo. S Specification Qo. S Mapping Qo. S Monitor Admission Control Qo. S Negotiation QMIO Service Objects Multimedia Communication Service Object Multimedia Session Service Object QMIO Network Service Object QMIO System Service Object Qo. S MIB

POSTECH DPNM Lab Qo. S Management Information Base (MIB) • Qo. S MIB can be used to monitor and control Qo. S values in multimedia services • Composed of 4 Informational Groups – Service, Application, System and Network • Qo. S MIB can be extended by adding the service-specific Qo. S management information

POSTECH DPNM Lab QMSO Services (1) • Qo. S Specification – The value of Qo. S parameter can be acquired using the three methods • device specification, off-line testing and on-line testing • Qo. S Monitoring – Qo. S monitoring modes: a query mode and a report mode – We use the report mode • Negotiation and Renegotiation – The Qo. S parameters are exchanged between server and client through peer-to-peer negotiation and layer-to-layer negotiation • peer-to-peer negotiation : between server and client • layer-to-layer negotiation : between the layers

POSTECH DPNM Lab QMSO Services (2) • Qo. S Mapping – Maps one layer Qo. S parameters onto other Qo. S parameters and vice versa (bidirectional translation) • One-to-one mapping, Mixing and Splitting (Demultiplexing) • Admission Control – The QMSO performs admission control at both layers : system and network – System level • device quality test, local schedulability test, end-to-end (EED) delay test and buffer allocation test – Network level • throughput test, rate control test and network EED delay test

POSTECH DPNM Lab Procedure of Qo. S Services

Prototype Implementation of Qo. S Management System POSTECH DPNM Lab

POSTECH DPNM Lab Video Conferencing Example with Qo. S Guarantees

POSTECH DPNM Lab Conclusion & Future Work • We presented a Qo. S management framework which includes Qo. S Management Service Object (QMSO) and a generic Qo. S MIB. As a realization of the Qo. S management framework, object-oriented Qo. S management middleware has been developed. • This provides distributed multimedia applications with Qo. S management APIs. It simplifies the development and maintenance of distributed multimedia applications, providing Qo. S guarantees. • We also described our effort on the prototype implementation of a Web-based Qo. S management system for MAESTRO. • The prototype Qo. S management system uses Orbix. Web to interface with the management server, which is implemented as a CORBA object. • This Qo. S management middleware can be used to provide Qo. S in CORBA-based as well as non-CORBA-based multimedia systems.

POSTECH DPNM Lab