network 기본2
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PowerPoint
HTTP Network Basic2016.11.30()
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I N D E X
01HTTP
01HTTP HTTP(HyperText Tranfer Protocol) .HTTP Request , Response ., Request Response .
ClientServerURL , .( .)HTTP (Client )PC runningFirefox browserserver runningApache WebserveriPhone runningSafari browser
HTTP request
HTTP response
HTTP request
HTTP response
client: browser that requests, receives, (using HTTP protocol) and displays Web objects server: Web server sends (using HTTP protocol) objects in response to requests
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01HTTP HTTP(HyperText Tranfer Protocol) Request Message HTTP Request .request line(GET, POST, HEAD commands)
header lines
carriage return, line feed at startof line indicatesend of header linesGET /index.html HTTP/1.1\r\nHost: www-net.cs.umass.edu\r\nUser-Agent: Firefox/3.6.10\r\nAccept: text/html,application/xhtml+xml\r\nAccept-Language: en-us,en;q=0.5\r\nAccept-Encoding: gzip,deflate\r\nAccept-Charset: ISO-8859-1,utf-8;q=0.7\r\nKeep-Alive: 115\r\nConnection: keep-alive\r\n\r\n
carriage return characterline-feed character
MethodURI
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HTTP request message: general formatrequestlineheaderlines
body
methodspspcrlfversionURL
crlfvalueheader field name
crlfvalueheader field name
~~
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crlf
entity body
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~~cr lf = carriage return line feed
01HTTP HTTP(HyperText Tranfer Protocol) Response Message Request Response .status line(protocolstatus codestatus phrase)
header lines
data, e.g., requestedHTML fileHTTP/1.1 200 OK\r\nDate: Sun, 26 Sep 2010 20:09:20 GMT\r\nServer: Apache/2.0.52 (CentOS)\r\nLast-Modified: Tue, 30 Oct 2007 17:00:02 GMT\r\nETag: "17dc6-a5c-bf716880"\r\nAccept-Ranges: bytes\r\nContent-Length: 2652\r\nKeep-Alive: timeout=10, max=100\r\nConnection: Keep-Alive\r\nContent-Type: text/html; charset=ISO-8859-1\r\n\r\ndata data data data data ...
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01HTTP HTTP(HyperText Tranfer Protocol) stateless ( )HTTP stateless . HTTP , Request Response . , HTTP Request Response .
HTTP Request Response . , cookie session .HTTP(HyperText Tranfer Protocol) Request URI HTTP URI(Uniform Resource Identifiers) .
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01HTTP HTTP(HyperText Tranfer Protocol) Method -> .
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01HTTP HTTP(HyperText Tranfer Protocol) Method -> .Request , Method . . , .HTTP 1.0 1.1 .Method typesHTTP/1.0:GETPOSTPUTDELETEHEADasks server to leave requested object out of response
HTTP/1.1:GET, POST, HEAD, TRACE, CONNECTPUTuploads file in entity body to path specified in URL fieldDELETEdeletes file specified in the URL field
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01HTTP TCP (Non-persistent)HTTP , Text , HTTP .Non-persistent HTTP: response time
time to transmit file
initiate TCPconnection
RTT
requestfile
RTT
filereceivedtimetime
HTTP:1. HTTP HTTP 80 www.someschool.edu TCP . TCP .
2. HTTP 1 TCP HTTP . /somedepartment/home.index .
3. HTTP 1 . /somedepartment/home.index , HTTP .
4. HTTP TCP TCP .( TCP )
5. HTTP ,TCP . HTML . HTML 10 JPEG .
6. JPEG 4 .RTT : Round Trip Time. = .
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01HTTP TCP (Persistent)TCP . TCP .( HTTP () , .)TCP , .persistent HTTP:server leaves connection open after sending responsesubsequent HTTP messages between same client/server sent over open connectionclient sends requests as soon as it encounters a referenced objectas little as one RTT for all the referenced objects
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Thanks. Have a good day.
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