http - What is the source of packet size in a GET request? -

i analyzing http network traffic different websites. have noticed packet size differs between websites.

i thought uri length decided packet size, yet different websites have different values. example "get /" has size of 339 1 website, yet 390 another.

also, noticed websites longer uri text have smaller packet sizes, , vice versa.

who responsible size of packet? browser, client, server or who?

thanks

first of all, discrepancy observing due either different host headers or passing of cookies between client , server, although referrer source of variation.

a given get packet of following format. in case of below example, packet size 361 bytes.

get / http/1.1\r\n host: google.com\r\n user-agent: mozilla/5.0 (windows; u; windows nt 6.1; en-us; rv:1.9.1.2) gecko/20090729 firefox/3.5.2 (.net clr 3.5.30729)\r\n accept: */*\r\n accept-language: en-us,en;q=0.5\r\n accept-encoding: gzip,deflate\r\n accept-charset: iso-8859-1,utf-8;q=0.7,*;q=0.7\r\n keep-alive: 300\r\n connection: keep-alive\r\n \r\n \r\n 

the first line determined url; however, subsequent lines headers. headers passed client communicate details of expected response , current request server.

additionally, response server packet. packet, too, have headers chosen explicitly communicate information other party.