Performance considerations for TCP/IP in wide area networks

The transport control protocol (TCP) was introduced in the early 1970´s to enhance the service of the Internet protocol (IP) and to provide reliable data transfer across heterogeneous packet switching networks. Since then it has probably become the most widely used transport protocol. Recently, several mechanisms, such as slow start and congestion avoidance, have been added to most TCP implementations to improve its performance and to help in controlling and avoiding congestion in high speed and long delay networks. This paper investigates the performance of TCP within wide area networks and quantifies the impact that the TCP built-in congestion control mechanisms, have on overall network performance. The results show that these mechanisms have improved overall network performance, minimized network vulnerability to congestion and made it possible for TCP to operate effectively in wide area networking environments. The results also show that although disabling the congestion control mechanisms may improve the application´s end-to-end performance, it introduces a higher proportion of busty traffic onto the underlying networks. This, however, makes the network more vulnerable to congestion and presents a challenge for network planning and engineering