الفهرس 
AbstractOnly 14 pages are availabe for public view
 |  | from | 119 |  |  |
| | | from | 119 | | |
Abstract
Real time applications such as audio and video are expected to be a dominant part in B-ISDN. However, the overall end-to-end network delay represents a major problem to the performance of such applications in packet switching. Therefore, audio and video packet discarding at statistical multiplexers is regarded as a means for dealing with this serious problem. In the previous investigations, two branches were discussed, the first used several queuing models to study and evaluate the discarding probability. On the other hand, the second concerned with the reduction of the discarding effects on the quality of the reconstructed signals. Although these investigations fit the problem to some extent, they have some deficiencies.
In this thesis, a queuing model is used to analyze the discarding process for audio systems, then it is extended to cover video systems as well. A more detailed study on the periods in which packet discarding occurs - which are called Blocking Periods - is performed since the overall discarding probability does not represent an accurate measure for the packet discarding in the network. The discarding probability during these periods, and the duration distribution of these periods and their repetition rate distribution are evaluated. Moreover, an improved technique for discarded cells recovery was suggested and it was -observed that it performs much better than the conventional techniques.
Finally, as a conclusion, the system parameters can be evaluated more accurately, and the system performance has greatly improved in comparison with the other conventional investigations.