1.大包发送
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udp限制64k,切割若干个小packet.
totalLength = x ;
perPack = 50k ;
count = x / 50 ; //计算包的数量
//组报文
2.URL:统一资源定位符。Uniform Resource Locator
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http://www.example.com/docs/resource1.html
HyperText Transfer Protocol
http://www.baidu.com:80/xx/x/x/x.txt
http://localhost:8080/xx/x/x/x.txt
http://www.baidu.com
protocal :// domain name : port / path
http://192.168.12.5:8080/a/b/c/d.txt?id=123&&name=tom
protocal : http
port : 8080
host : 192.168.12.5
authority : host : port //授权
file : /a/b/c/d.txt?id=123&&name=tom //path + ? + query
path : /a/b/c/d.txt
query : id=123&&name=tom
header :消息头
body :消息主体
