A study of QoS-based multimedia data retrieval systems

Multimedia applications that treat various types of data like videos, audios, and images are becoming popular amongst the Internet users. Assuming best-effort networks as the infrastructure, we are developing a multimedia data retrieval system based on QoS (quality of service) concept that searches and retrieves various types of multimedia data from plural multimedia data archives. As one of QoS parameters, we select the user´s response time. Since the response time is related with network throughputs, throughput measurement becomes an important technology in the system. So far, we have developed a mechanism to decide a retrieval order of multimedia data that match with the user´s searching request. The mechanism is called QoS scenario and it balances the user´s searching request (keyword matching) and the QoS factor related with the user´s response time that can be determined by the throughput measurement. The QoS scenario was used in the first version of our multimedia data retrieval system. In this paper, we study the active and passive throughput measurement technologies. Also, a multimedia data structure is introduced on the basis of the Dublin Core that has been standardized. Owing to the multimedia data structure, the system is able to hold interoperability and wide-area-network search and retrieval can be realized.