The modelling of TCP traffic in MPLS networks

Villet, Marcel (2003-04)

Thesis (MSc)--Stellenbosch University, 2003.

Thesis

ENGLISH ABSTRACT: The Internet has experienced tremendous growth in the last three decades and has emerged as a platform to carryall forms of communications including voice, video and data. Along with this growth came the urgency for quality of service (QoS) controls in IP networks as different types of traffics have different service requirements. Although the IP protocol is able to scale to very large networks, it does not provide sufficient functionality for traffic engineering in order to enable QoS control. Multi-protocol label switching (MPLS) is a new routing technology that enhances IP with some QoS concepts from ATM and uses relatively simple packet forwarding mechanisms. MPLS has the ability to perform traffic engineering and QoS control by routing traffic flowson virtual connections called label switched paths (LSPs) which are assigned capacity. A large portion of the traffic carried on the Internet consists of data traffic in the form of TCP traffic. This thesis investigates several TCP models to find the ones most suitable to represent TCP traffic in MPLS networks. The models consist of three types. The first type models a single TCP source and the second type models a fixed number of TCP sources. The third type models an infinite number of TCP sources. The models were evaluated by comparing their throughput predictions and results obtained from simulation experiments that were done with the widely-used simulator ns. We also present a simple derivation of the 1/,;e law for the TCP congestion window size where e is the packet loss probability.

AFRIKAANSE OPSOMMING:In die afgelope drie dekades het die Internet beduidende groei ervaar, soveel so dat dit ontluik het as 'n medium om alle tipes van moderne kommunikasies te hanteer insluitend telefoon, video en data. Hierdie groei het gepaard gegaan met die behoefte na diensvlak (QoS) meganismes in IP netwerke aangesien verskillende tipe kommunikasies verskillende diens vereistes het. Alhoewel die IP protokol skalleerbaar is tot baie groot netwerke, voorsien dit nie voldoende funksionaliteit om QoS beheer toe te pas nie. "Multi-protocol label switching" (MPLS) is 'n nuwe roeterings tegnologie wat IP aanvul met QoS konsepte van ATM en dit maak gebruik van relatief eenvoudige pakkie versendings-meganismes. MPLS het die vermoe om netwerk-verkeer reeling en QoS beheer toe te pas deur verkeers-strome te roeteer op virtuele roetes genaamd "label switched paths" (LSPs) aan wie kapasiteit toegeken is. 'n Beduidende gedeelte van Internet-verkeer bestaan uit TCP-verkeer. Hierdie tesis ondersoek verskillende modelle van TCP om die te vind wat die mees geskik is om TCP verkeer in MPLS netwerke te verteenwoordig. Drie tipes modelle is ondersoek. Die eerste tipe moduleer 'n enkele TCP verkeersbron en die tweede tipe moduleer 'n vasgestelde aantal TCP verkeersbronne. Die derde tipe moduleer 'n oneindige aantal verkeersbronne. Die modelle is geevalueer deur hul voorspellings van die tempo van data transmissie te vergelyk met resultate van simulasies. Die simulasies is gedoen met die veelgebruikte simulator ns. Hierdie tesis bevat ook 'n eenvoudige afleiding vir die 1/,;e wet vir die TCP oorlading venster grootte met e die verlies waarskeinlikheid van 'n netwerk pakkie.

Please refer to this item in SUNScholar by using the following persistent URL: http://hdl.handle.net/10019.1/53658
This item appears in the following collections: