18 lines
476 B
Markdown
18 lines
476 B
Markdown
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Lecture Topic: HTTP
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# Conditional Get
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## Last-Modified
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You can check the Last-Modified header to only get contents if the contents are newer than the contents of the cache
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## ETag
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Use the hash of an object to check for modification to solve cache invalidation problem
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## TCP and HTTP
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HTTP runs on top of TCP
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- Client initiates TCP request to server
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- Server accepts TCP connection
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- Clint confirms request
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- Three way handshake
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## Non-persistent HTTP
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RTT = Round trip time
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