With the rise of cloud computing, distributed services are supplanting the role of traditional host-based systems. The performance of such applications is dependent on the properties of the network that connects their nodes. However, measurement studies have shown that the end-to-end performance for almost all network paths is suboptimal with regards to latency and throughput-alternative paths which could improve upon those metrics can be seen to exist, but applications have no means by which to exploit them. The performance of network paths can be improved with detour routing, an approach which can enhance path performance by redirecting end-to-end communication flows via tertiary detour nodes, exploiting otherwise unrealised connectivity in the network. However, discovering effective detour nodes for arbitrary end-to-end Internet paths incurs a high measurement cost, and discovering such nodes in a scalable fashion remains an open problem. Existing proposals have been restricted to optimising simple metrics, such as latency, or have exploited third-party infrastructure to gather measurements. Where they have been evaluated within a practical context, such systems have shown limited performance improvement, especially with regards to throughput. In this thesis, we show through large scale measurement that the existence of detour routes is widespread, and develop a concrete architecture for improving latency and throughput on arbitrary Internet paths. We find that to achieve effective detour routing in practice, it is necessary to consider entirely separate approaches for latency and throughput. We propose two novel approaches for scalable detour discovery: a network-structure based approach for discovering latency detours, which identifies detour paths by analysing AS-paths; and a statistical approach for discovering bandwidth detours, which identifies the most effective detours based on their aggregate detouring potential. Furthermore, we establish that network-layer detouring cannot be effective for optimising TCP throughput and instead develop a transport-layer approach, which is demonstrated to achieve significant bandwidth improvements over a diverse range of Internet paths.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:666484 |
| Date | January 2014 |
| Creators | Haddow, Thom |
| Contributors | Pietzuch, Peter |
| Publisher | Imperial College London |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/10044/1/25886 |
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