TCP Performance Enhancement over UMTS Network with RNC Feedback

TCP optimization for wireless networks to deal with packet losses due to fading, shadowing and contention should preferably maintain TCP end-to-end semantics with minimal dependence on intermediate nodes. The development of advanced 3G networks and services makes it necessary to find a way of improving TCP's efficiency and resource utilization. Previous research on this issue suggests that TCP needs radio network feedback to distinguish wireless related losses from congestion related losses. This paper presents such a mechanism that notifies the TCP sender of any noncongestion related losses by introducing a proxy at the RNC node of the UMTS network. Only a minimal change to the standard TCP is required to achieve this. OPNET is used in this study and the simulation results show that the proposed scheme significantly improves the TCP performanc

Performance Evaluation of Real Time Traffic in LTE Networks

Long-Term Evolution, commonly known as 4G LTE, is a standard for wireless communication of high-speed data for mobile phones and data terminals. TCP protocol plays a significant role in LTE network. Congestion control algorithm is an integral module of TCP that directly determines the performance of the protocol in IP Network. Many TCP variants like TCP-Vegas, TCP-Tahoe, TCP-Reno, TCP-NewReno, TCP-SACK, and TCP-FACK have been proposed for high bandwidth real time services in LTE network [1]. These TCP variants can be used to improve quality of service parameters i.e., throughput, average delay and lost packet in LTE network [2]. Since LTE systems has high-data-rate, low-latency and packet-optimized radio access technology therefore these parameters directly affect the traffic. In this paper, complete LTE Network is simulated using the OPNET simulator to evaluate network performance in real time [3]. The simulated LTE network is tested for each type of TCP protocol and the result is monitored for throughput, end to end delay, http and FTP traffic, re-transmission response time and packets drop etc and the results are plotted. At the end, it is concluded that TCP New Reno has outperformed in terms of throughput, re-transmission rate and http uplink and downlink traffic. In medium size network, the performance of Reno is satisfactory. Similarly changes in mobility rate enhance the performance of TCP Reno in other congestion control algorithms. On the other hand, TCP Cubic is found to be the worst performer for throughput, re-transmission rate and http traffic parameters. Keywords: LTE, QoS, EUTRAN, TCP, http, Opne