OST/otn/login/loginAysnSuggestHTTP/1.1Host:kyfw.12306.cnConnection:keep-aliveContent-Length:203Accep
OST /otn/login/loginAysnSuggest HTTP/1.1Host: kyfw.12306.cnConnection: keep-aliveContent-Length: 203Accept: */*Origin: https://kyfw.12306.cnX-Requested-With: XMLHttpRequestUser-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.95 Safari/537.36Content-Type: application/x-www-form-urlencoded; charset=UTF-8Referer: https://kyfw.12306.cn/otn/login/initAccept-Encoding: gzip, deflateAccept-Language: zh-CN,zh;q=0.8,en;q=0.6Cookie: JSESSIONID=059319E9BB0614197D515D6A0213EC58; _jc_save_fromStation=%u6DF1%u5733%2CSZQ; _jc_save_toStation=%u5409%u5B89%2CVAG; _jc_save_fromDate=2015-02-13; _jc_save_toDate=2014-12-16; _jc_save_wfdc_flag=dc; BIGipServerotn=854589962.50210.0000; _jc_save_detail=true; current_captcha_type=C上面的是请求头，下面的是相应头HTTP/1.1 200 OKDate: Mon, 29 Dec 2014 02:48:04 GMTServer: Apache-Coyote/1.1X-Powered-By: Servlet 2.5; JBoss-5.0/JBossWeb-2.1ct: c2_50Content-Type: application/json;charset=UTF-8Content-Length: 164X-Via: 1.1 zhj168:5 (Cdn Cache Server V2.0)Connection: keep-alive请求头描述了客户端向服务器发送请求时使用的http协议类型，所使用的编码，以及发送内容的长度，refer，等等。refer干嘛的，一般用来做简单的防跨站攻击。
相应的响应头用来描述服务器回给你对所返回的content的一些一些描述，我是什么服务器，我返回的是啥编码，我返回的内容有多长等等。
