Penentuan Contention Window untuk Meningkatkan Kinerja Trafik Video Up Link pada Jaringan WiMAX

Abstract

WiMAX technology can support quality of service which is required in multimedia services, such as transmission of video signals. However, when the WiMAX was used to transmit video traffic on up link channel, it will occur increasing of delay while video bit rate and frame duration were increased This will reduce the performance of video communication, which is requiring low delay. Therefore, it is important to minimize increasing of delay in video transmission. One of efforts is to determine the proper contention window as part of bandwidth request mechanism. Size of contention windows must be adjusted to the number of subscriber station that occupies the same channel multiplied by size of frame duration. To see effect of frame duration and bit rate traffic changes, so a few combination of both parameters were selected and then simulated using NS 2.34 simulator. Method of determining value of contention window proposed success to reduce video transmission delay until 20.27% for variation of bit rate traffic. The proposed method also minimizes delay up to 19. 69% of variation of frame duration. On the other hand, proposed method does not affect the value of throughput and packet loss.