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Traffic Control in Data Center Networks
PhD Thesis Proposal Defence Title: "Traffic Control in Data Center Networks" by Ahmed MOHAMED ABDELMONIEM SAYED Abstract: Cloud computing defines a new computational approach that has led to the restructuring of the whole IT industry, by making computing available to customers at a reasonable cost in a man- ner similar to governments or private companies providing utilities (water, electricity, gas) to the citizens. This new computing paradigm is becoming widely popular and increasingly replacing the legacy infrastructures within the public and private IT sectors. As a natural consequence, data centers have seen a dramatic increase in their rate of deployment energized by a sense of compe- tition among big Cloud Service Providers (CSP) such as Amazon, EMC, Google, Microsoft and Softlayer. It is widely believed that in the near future any piece of data or information that circu- lates the Internet originates in fact from some data center. Data centers consist of tens of thousands of servers mutually interconnected via high speed network interconnects, running a large number of applications that serve a huge number of users simultaneously. As such these applications typi- cally adopt a multi-tiered design model where several services residing on distributed servers work together to satisfy a single client request. Hence, the overall performance of such applications depends greatly on the ability of the underlying communication network to provide efficient and timely data transfers. In this thesis proposal, first, we give the background of the architectural design of data center networks and inspect how such networks would affect application performance with more attention to network congestion and related work. Then, we explore and analyze the causes of performance degradation in such high-throughput low-latency Data Center Networks (DCNs) to provide guide- line in the design of an efficient congestion control scheme. Motivated by the popularity of TCP as the major transport protocol in data centers, we pro- pose two novel TCP-AQM schemes to improve TCP efficiency without incurring any changes to the TCP protocol stack. First, we present an equal-share allocation AQM “RWNDQ” for DCN switches. RWNDQ relies on TCP flow control to efficiently and explicitly control TCP’s sending rate and hence achieve improved performance. Then, to address the popularity, scale and severity of Incast congestion in datacenters, we propose an Incast-Aware Queue Management “IQM” system which predicts possible on-set of Incast events and proactively slows down and limits everybody to a constant minimal rate. We also address the recent increase in popularity of DCNs adopting the Software Defined Networking (SDN) paradigm which differs from the conventional way of networking. To this end, we re-design our proposed systems to leverage the powerful control of SDN-based DCNs in order to implement SDN-based congestion and traffic control schemes. Finally, we demonstrate the effectiveness of our proposals by conducting simulation and real- testbed experiments on various network topologies. Then, we point out possible future directions to be explored before final thesis completion. Date: Wednesday, 1 March 2017 Time: 2:30pm - 4:30pm Venue: Room 4475 (lifts 25/26) Committee Members: Dr. Brahim Bensaou (Supervisor) Dr. Pan Hui (Chairperson) Prof. Gary Chan Dr. Kai Chen **** ALL are Welcome ****