The forwarding delay and throughput of a proxy server play significant role in the overall network performance. It is widely known that the forwarding delay of proxy¡¦s application layer is much larger than that of lower layers. This is because for a general purpose operating system, the receiving or sending data in application layer needs to move data through the TCP/IP stack and also cross the user/kernel protection boundaries.
TCP Splice can forward data directly in TCP layer without going up to the application layer. This can be achieved by modifying the packet headers of one TCP connection from the original server to the proxy so that the TCP connection can be seamlessly connected to another TCP connection from the proxy to the client.
To maintain the caching ability of proxy, TCP Tap can duplicate packets before they are forwarded by TCP Splice. The duplicated packets are copied into a tap buffer, so the application layer can read data from the tap buffer. We fully utilize the original TCP receive queue as the tap buffer and allow application layer to read data as usual.
We chose Linux as the platform for experiment. The TCP Splice and Tap are implemented as Linux modules. Finally, we develop an HTTP proxy to test and verify our implementation. It is shown that the performance of proxy in terms of lower forwarding delay, higher throughput, and increased CPU utilization, can be improved significantly.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0710102-112353 |
| Date | 10 July 2002 |
| Creators | Wang, Cheng-Sheng |
| Contributors | Chung-Ming Huang, Ce-Kuen Shieh, Tsang-Ling Sheu, Wei-Kuang Lai, Shie-Jue Lee |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0710102-112353 |
| Rights | campus_withheld, Copyright information available at source archive |
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