| Research Abstract |
In this study, in order to establish the essential technology to realize the highly enhanced high-speed multimedia network in the future, the following two techniques are focused on and actually studied in detail ;
1. Construction technology of the multimedia router.
2. On-demand retrieval and information delivery techniques using hierarchical link sharing.
As for the issue 1., fast MPLS label look-up mechanism using CAM(Content Addressable Memory) has been proposed to implement the MPLS traffic engineering. As a result of the quantitative evaluation by using the existing CAM speed, Our proposed mechanism can be attained to 10Gbps processing speed. Next, hierarchical buffer management scheme has been proposed, where buffer space and transmission
speed to the output links are shared fairly taking into account the hierarchy of output ports, priority class, and flows. Furthermore, proposed buffer management scheme was designed by hardware level specification language partly.
As for the issue 2., Block transfer type VOD scheme called Burst-VOD suitable for the future broadband network has been proposed, and main and fundamental parts were implemented by software. Proper behavior of the prototype system was confirmed in the IP network. Next, as way to enhance the QoS for general MPEG video transfer, we presented the cooperative combination of the End-to-End control such as priority class transfer according to the frame attributes, i.e. I, P, B frames, frame-base dropping and GOP-base shuffling, and the intra-router control such as class-base RED(Random Early Detection), class-base buffer scheduling RR(Round Robin) and Weighted RR(WRR). Then, these combinational methods are evaluated by computer simulation. As results, in particular, it is confirmed that WRR is very effective though it requires quite complicated weight estimation mechanism, and RED control to the B-frame class which belongs to lowest priority class is more effective, and so on.
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