2002 - cesnet

9 Quality of Service in HighspeedNetworksThis project deals with theoretical and practical aspects of implementing serviceswith defined quality (Quality of Service, QoS) in high-speed networks.A particular emphasis is on the high performance of the entire network communication,or the end-to-end performance.The project has its own website 12 , where visitors can find articles, presentations,results of experiments and created software. For a summary of the mostimportant project outputs, see below:9.1 QoS Implementation on JuniperRoutersIn the previous work, we have learned about the possibilities of implementingQoS on Cisco routers, on which the CESNET2 network is based. Among othersignificant producers of routers, there is Juniper Networks. Routers producedby this company are used within some backbone lines of the European networkGéant. The Premium IP service is being considered for implementation in theGéant network, in order to provide for priority to certain data packets withrespect to the rest of network traffic. We therefore checked the possibilities ofimplementing QoS on Juniper routers.For the purposes of experimentation, we used M10 type, with a performanceand offer of ports comparable to that of the Cisco 7500 model. All Juniper routershave almost identical hardware architecture and make use of the sameoperating system – JUNOS. We therefore expect that the collected data are alsovalid for other types of routers.We based our experiments on the latest available version of the operating system,JUNOS 5.0. At present, there is a newer version available, offering severalother functions useful for the purpose of QoS implementation. For the experimentconfiguration, see Figure 9.1.We measured the basic characteristics of QoS, i.e., throughput, loss rate, delayand jitter, with the use of the RUDE/CRUDE programs, together with qosplot,which we created during the project.As an example of an evaluated feature, we would like to point out the WRR(Weighted Round Robin) algorithm, used by Juniper routers for the control of12http://www.cesnet.cz/english/project/qosip/High-speed National Research Network and its New Applications 2002121