29 lines
1.3 KiB
Markdown
29 lines
1.3 KiB
Markdown
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Lecture Topic: Web Protocols
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# Encapsulation/Decapsulation
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Each layer of a network adds a header, that encapsulates the rest of the data
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When a packet is decapsulated, each layer strips away its header after it is done processing
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# Network Applications
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Applications are *distributed* since they involve multiple end systems that exchange dat which each other
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## Application Architectures
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Dictates how applications interact on a network
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- Client/Server architecture
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- Server: An always on host which services requests from many other hosts
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- Data is often stored on the server
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- Data centers can be used to create powerful virtual servers
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- Clients: Connect through to the server
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- Peer to peer architecture
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- No always on server
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- Arbitrary end systems directly communicate
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- Peers request service from other peers and provide service in return to other peers
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- Self scalability: New peers bring new service capacity as well as new service demands
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- Peers are intermittently connected and change IP addresses (complex management)
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- Examples include BitTorrent (P2P file sharing)
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# Basics of Web and HTTP
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Invented by Tim Burners-Lee
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Client Server model
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- Client is a web browser that requests and receives, and then displays web objects
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- Server is a web server that sends objects in response to
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