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| Author(s): |
Adilson Eduardo Guelfi
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Escola Politécnica (EP/BC) |
| Defense date: | 2002-06-28 |
| Examining board members: |
Sergio Takeo Kofuji;
Martha Ximena Torres Delgado;
Edward David Moreno Ordoñez;
Pedro Frosi Rosa;
Joao Antonio Zuffo
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| Advisor: | Sergio Takeo Kofuji |
| Abstract | |
Based on the current third generation network paradigm that consolidates widely varying capabilities, characteristics and medias, distributed multimedia applications request communication services more and more flexible, and that also support Quality of Service (QoS) parameters. Such parameters are closely related with several available communication protocols, existing network infrastructures and other additional properties. They should still be treated in an efficient and integrated way into end systems and network. On the other hand, it is desired that future generation multimedia applications present a good level of modularity, availability and scalability for a great variety of devices and heterogeneous environments that are spreaded for extensive areas. This way, regarding the current context of possible network technologies, we can see that applied general infrastructure could satisfactorily support the desired requirements through its resources as bandwidth, delay and losses control etc. However, the development of such types of applications look likes that it was not stimulated sufficiently to use in an including way all the attributes that are being provided. Thus, to support common users and/or programmers in general, the presence of a \"middleware\" could provide a certain level of flexibility and transparency for the scope of multimedia application communication requirements, doing with that they could be configured and monitored in a coherent way. Inthis context, the goal of this thesis is to describe architecture, implementation and evaluation of a middleware dedicated to provide the management of multimedia communication services in third generation networks. Basically, general middleware aspect regards the presence of modules, whose functions is to control the following items: multimedia sessions, QoS and its associated management processes (specification, mapping, adaptation, monitoring and ) renegotiation), data and control connections, security, session scheduling, treatment of heterogeneity and legacy applications, logs and billing. Initially, after QoS specification by an user, the middleware functional schema defines a specific service context through and instantiation of the corresponding modules, which they interact to each other during the whole multimedia session to maintain contracted QoS. For the middleware proposed in this work, operation and applicability aspects were determinated through the creation of a prototype that it supported client and server sides of a VoD (Video on Demand) distributed multimedia application. Such prototype allowed an experimental evaluation, whose results showed several practical and validation conclusions that demonstrated the feasibility related to the performance and quality of management services applied on heterogeneous communication environments. (AU) | |