Patent ID: 8036112
Filing Date: 2011-10-11
Classification: H04L

Abstract:
1. A method of adjusting the transmission rate for a window-based transport control protocol (TCP) used by a sender to transmit data to a receiver across a network connection of a computer network, the method comprising the steps of: detecting a packet drop in the network; detecting a current congestion window variable value at the time of the packet drop, wherein the current congestion window variable value represents the size of the current congestion window, the size of the current congestion window identifying the maximum number of packets the sender can send to the receiver before waiting for an acknowledgement from the receiver; filtering the current congestion window variable value using a discrete time low pass filter to estimate a new congestion window variable value; decreasing the TCP transmission rate by decreasing the current congestion window variable value to equal the new congestion window variable value in response to the packet drop in the network; and transmitting the data to the receiver at the decreased TCP transmission rate; wherein the step of filtering the current congestion window variable value using a discrete time low pass filter to estimate a new congestion window variable value further comprises the steps of: identifying a congestion type corresponding to the packet drop in the network; determining a time interval of the packet drop; and filtering the current congestion window variable value using a discrete time low pass filter to estimate a new congestion window variable value according to the following relation: where: cwnd cwnd 1/τ is the cut-off frequency of the low pass filter; t cwnd_sample last_cwnd_sample