The purpose of this study was to examine the performance of transport Protocols by combining explicit router feedback with different window control algorithms. TCP does not perform well in networks with high bandwidth and delay. Two different approaches to alleviate this problem namely, various window control algorithms and eXplicit Congestion Control protocol were studied and their performance were observed when they are combined and the window control algorithm that gives the best results when combined with the eXplicit Control Protocol is chosen. Simulations were done in ns-2. A modified fourth-root Square Increase Multiplicative Decrease window control algorithm was found to significantly improve the performance of the existing eXplicit Control Protocol (XCP) in terms of fairness, utilization, congestion window and the number of packets being sent. Other window control algorithms were also evaluated but did not improve the performance of the current XCP. Thus, a new window control algorithm is obtained by modifying the existing Square Increase Multiplicative Decrease (SIMD) algorithm to suit the eXplicit Control Protocol and the resulting graphs show a considerable improvement in performance to the existing eXplicit Control Protocol.