Ghassan A. Abed

Traffic Modeling of LTE Mobile Broadband Network Based on NS-2 Simulator

Recently, Long-Term Evolution (LTE) is the result of ongoing work by the Third Generation Partnership Project (3GPP) toward Fourth Generation (4G) systems. LTE will be used for mobile, fixed and portable wireless broadband access, and will offer several benefits to operators, aimed at increasing capacity, reducing network complexity and thus lowering deployment and operational costs. It will enable operators to meet the growing demand for mobile data solutions, making it possible for richer services to be delivered to consumers more cost effectively. The targets for LTE indicate bandwidth increases as high as 100 Mbps on the downlink, and up to 50 Mbps on the uplink. However, this potential increase in bandwidth is just a small part of the overall improvement LTE aims to provide. This study illustrates the model and representation of LTE links and traffics using NS-2 network simulator and observation of TCP Reno performance investigated. The Evaluation of the network performance with TCP Reno is mainly based on congestion window behavior, throughput, average delay and lost packet.

Appraisal of Long Term Evolution System with Diversified TCP's

Long Term Evolution (LTE) is a 4G wireless broadband technology developed by the Third Generation Partnership Project (3GPP), and its represent the competitiveness of Universal Mobile Telecommunications System (UMTS) for the next 10 years and beyond. The concepts for LTE systems have been introduced in 3GPP release 8, with objective of high-data-rate, low-latency and packet-optimized radio access technology. In this paper, performance of different TCP variants over LTE network investigated. This paper describes analysis of TCP-Vegas, TCP-Tahoe, TCP-Reno, TCP-New reno, TCP-SACK, and TCP-FACK, based on NS-2 Simulator with full modeling of all traffics of LTE system. The analysis of TCP performance over LTE ensures that all TCPs have a similar throughput and the best performance return to TCP-Vegas than other variants.

A comparison and analysis of congestion window for HS-TCP, Full-TCP, and TCP-Linux in long term evolution system model

TCP performance over high bandwidth network still represents the major challenge, since the large numbers of data flows through bottleneck, TCP forces a high packet loss rate and that causing delays that users are likely to notice. Congestion window (cwnd) is maintained, which indicates the number of Transmission Control Protocol (TCP) segments that the existing connection is capable of holding safely. In high bandwidth networks, such as 4th Generation (4G) Long Term Evolution (LTE) systems, we expect a high rate of traffics, and then each TCP variants perform a different behavior of cwnd. In this study, three TCPs variants: TCP-Linux, FullTCP, and High Speed TCP (HSTCP), observed and the cwnd of each variant analyzed and compared with other two variants, over a model of high bandwidth network topology using network simulator (NS-2). All these TCPs tested under high rate of data transferred through a bottleneck. We found that each variant can provide a good cwnd size performance and stability but the differences was in cwnd phases such as slow start threshold (ssthresh), congestion avoidance, slow-start, and maximum congestion points.

Influence of parameters variation of TCP-Vegas in performance of congestion window over large bandwidth-delay networks

Major challenge for TCP is to keep up the new and modern generation in communications networks such as networks with large bandwidth and long delay because when TCP applies on next generation networks will suffer from degradation in performance. The reason behind this shortcoming in performance is due to the congestion control mechanisms supported by TCP variants where these mechanisms depending on linear or exponential growth to increasing the transmission window. In TCP-Vegas, in spite of the performance degrades if applied in large bandwidth-large delay networks, but it can give acceptable performance when TCP receiver support delayed acknowledgment (ACK). Vegas congestion control algorithm developed in different manner and not support the same techniques used in other TCP source variants, because it minimizes the delay in connection queue and also provides a far less in loss of packets where that increase the throughput of network. This article presents results from a series of simulation experiments designed to study TCP Vegas performance in large bandwidth and large delay network model using NS-2 network simulator. The analysis and observation of Vegas behavior performed using the main two parameters, alpha and beta, to configure the congestion window (cwnd) phases. After used multiple values, the behavior of cwnd of TCP Vegas is very sensitive to the variation of the parameters values and then we got a wide variety results corresponding to parameters variation.

Links Interfacing Demonstration of LTE-Advanced Networks Using NS-2 Modeller

Society of 3rd Generation Partnership Project (3GPP) is presently evolving Long Term Evolution Advanced (LTE-Advanced) as a development of the standard of LTE. This generation aims to produce specifications for a new radio-access technology geared to higher data rates, low latency and greater spectral efficiency. LTE-Advanced is an evolutionary step in the continuing development of LTE where the description in this article is based on LTE release 10. This paper provides detailed interfacing parameters and factors, which effect to implement the traffics and links of the transport layer for LTE-Advanced networks using the network simulator NS-2. Furthermore, it provides a deeper insight for the interface of protocol stacks, user plane, and control plane of protocol stack with the investigation to the links between the main parts LTE-Advanced structure in terms of events, activities, organizations and other factors that have played an important role over transport layer.