Quality of Service Provisioning in Optical CDMA Packet Networks

An enhanced media access control (MAC) layer protocol that uses the signaling method benefits of the physical layer in order to provide different levels of quality to different users in optical code-division multiple-access (OCDMA) packet networks is presented. In the proposed network architecture the users are categorized into two classes of service, one having a higher quality level and the other having a lower quality level. Users of each class transmit at the same power level and different from the other classes' users. Also, the MAC of each user estimates the amount of interference on the channel and adjusts the packet transmission's time to improve network performance. Through simulation it is shown that the combination of appropriate power assignment to users and proper MAC algorithm parameters can provide various quality of service (QoS) metric levels on metrics such as normalized throughput and packet error rate. This is achieved by dividing the available resources of the OCDMA network between the users of each class. To make the QoS provider method more practical in data communication networks, we have studied the fairness issue by defining two parameters related to the normalized throughput of each class.