Implementation and performance analysis of switch fabric schedulers with a new accurate simulator software


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Elektrik ve Elektronik Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2014

Öğrenci: AHMET ADA

Danışman: ŞENAN ECE SCHMİDT

Özet:

The switches and routers in computer networks forward the incoming packets that arrive at input ports to their output ports where the connections between input lines and output lines are made by a switch fabric. If the fabric speed can match the aggregate capacity of all input ports, the queuing of the packets is at the output ports. Such output queued arrangements yield the best throughput and delay for the packets together with different levels of Quality of Service Support (QoS) to different flows. However, the speed limits for these fabrics result in queuing at the input ports in practical switch/router implementations. Such devices require the scheduling of the switch fabric which is the decision of the matched input output port pairs. To this end, the design of these fabric schedulers for achieving high throughput, low delay as well as QoS support is an important research problem. The first contribution of this thesis is a software simulator that is called SwitchSim that accurately simulates switch fabric schedulers. The design of the simulator is modular with well defined interfaces following an Object Oriented Approach to enable integrating different scheduler algorithms and traffic generation patterns. It is important to note that SwitchSim is verified by comparing its results to a hardware scheduler together with to the results of the legacy ISLIP scheduler. The second contribution of the thesis is extending ISLIP to support different priority flow to support QoS. Experiments are carried out using SwitchSim to evaluate the proposed fabric schedulers with QoS support and their results are presented with discussions. The results show that upto loads of 70% the proposed algorithms can provide less delay to the high priority flows without starving the low priority flows.