Exploiting cross layer feedback To enhance up link tcp performance For best effort applications in IEEE 802 16 BWA systems

Abstract

newline It is known that the performance of TCP has got degraded in wireless and newlinehybrid wired wireless networks The main reason for such a degradation in newlinethese networks is its inability to discriminate packet losses due to network newlinecongestion from those due to wireless link errors In order to provide reliable newlinewireless link IEEE 802 16 supports Automatic Repeat reQuest ARQ using newlinewhich the receiver can request the retransmission of MAC PDUs received in newlineerror MAC PDU refers to Medium Access Control Protocol Data Unit The newlineretransmissions can be carried out for a fixed number of retries within its lifetime newlineTo transmit PDUs of Best Effort BE applications the SS acquires newlinebandwidth BW allocation on a contention basis BE applications are newlineserviced based on the space availability Hence even if ARQ is enabled for newlineBE connections there is still a possibility of wireless loss which may be due newlineto repeated error and or lack of BW allotment So once a drop has occurred newlineit is hard to pin point the exact reason for the drop newline