Introducing TCP in a 3G load generator

Abstract: In this thesis we investigate, implement and evaluate a solution for introducing the TransmissionControl Protocol (TCP) into the software of a load generator. The load generator is a simulator usedfor simulating end-user generated activities in the Universal Mobile Telecommunication System(UMTS) network. The purpose of simulating traffic on the network is in this case to verify thefunctionality and robustness of the Radio Network Controller (RNC) node within the UMTSnetwork.TCP is a protocol that provides reliable data transfer over unreliable underlying networkprotocols. It is used as the main transport protocol of the Internet, thus it is also used in the UMTSnetwork in order to provide connectivity for user equipment, such as 3G mobile phones, to servicesover the Internet. For the load generator to be able to produce more realistic traffic scenarios is itdesirable to give it the ability to use TCP.This thesis presents a solution of the problem where an open-source implementation of the TCPfunctionality was chosen, ported to the running platform of the load generator and then tested in asimulated test environment. The choice of the open source implementation of TCP was made byperforming an investigation of available options. In the investigation an open source TCP/IP stackcalled lwIP was chosen. lwIP was then ported to the running platform of the load generator bywrapping and modify the source code. The tests of the ported TCP implementation were made in asimulated test environment with focus on testing basic TCP functionality. The tests showed that theTCP implementation produced provided the basic functionality that was asked for.