Patent ID: 9124426
Filing Date: 2015-09-01
Classification: H04L

Abstract:
1. A sliding purge window and snapshot feedback method to reduce packet losses and synchronization time, and improve transport control protocol throughput in a wireless network between a receiver having a receive window, fed by a fragmentation buffer and a re-assembly buffer to re-assemble fragments of packets received, and a transmitter having a transmission window and that monotonically assigns each packet sent by the transmitter with a packet ID number up to a maximum packet ID number, said wireless network using a Hybrid Automatic Repeat Request transmission scheme having a re-transmission logic that ensures an oldest unacknowledged packet is re-transmitted first wherein the sliding purge window method ensures that the packets in the receive window match the packets in the transmission window such that if there is a transmission error the Hybrid Automatic Repeat Request transmission scheme recovers and the receiver and transmitter remain in synchronization comprising: said receiver having a sliding purge window; setting a threshold packet number for said sliding purge window that is less than the maximum packet ID number; said receiver purging an oldest received packet from said re-assembly buffer and fragmentation buffer each time a fragment is received by said receiver that belongs to a packet having a packet ID number that is greater than the packet ID number of a packet in the fragmentation buffer and re-assembly buffer by said threshold packet number; said transmitter regularly storing a snapshot of the packets in the transmission window and said transmitter sending said snapshot to said receiver when transmission bandwidth allows; and, then said receiver receiving and comparing said snapshot to packets in said sliding purge window and when the comparison shows a difference in said snapshot and said sliding purge window nonmatching packets in said sliding purge window are purged by said receiver.