计算机网络实验报告一

1计算机网络实验报告一班级：智能1401姓名：蒙寿伟学号：201408070120一、HTTP1.TheBasicHTTPGET/responseinteraction实验步骤：1.Startupyourwebbrowser.2.StartuptheEtherealpacketsniffer,asdescribedintheIntroductorylab(butdon’tyetbeginpacketcapture).Enter“http”(justtheletters,notthequotationmarks)inthedisplay-filter-specificationwindow,sothatonlycapturedHTTPmessageswillbedisplayedlaterinthepacket-listingwindow.(We’reonlyinterestedintheHTTPprotocolhere,anddon’twanttoseetheclutterofallcapturedpackets).3.Waitabitmorethanoneminute(we’llseewhyshortly),andthenbeginEtherealpacketcapture.4.Enterthefollowingtoyourbrowser实验结果：1.IsyourbrowserrunningHTTPversion1.0or1.1?WhatversionofHTTPistheserverrunning?结果：我的浏览器HTTP的版本是1.1，服务器的HTTP版本是1.12.Whatlanguages(ifany)doesyourbrowserindicatethatitcanaccepttotheserver?结果：浏览器可以接受的语言版本：zh-Hans-CN,zh-Hans;q=0.8,en-US;q=0.5,en;q=0.33.WhatistheIPaddressofyourcomputer?Ofthegaia.cs.umass.eduserver?结果：电脑的IP地址为192.168.1.8服务器IP为:128.119.245.1224.Whatisthestatuscodereturnedfromtheservertoyourbrowser?结果：状态代码是200（请求成功）5.WhenwastheHTMLfilethatyouareretrievinglastmodifiedattheserver?结果：Last-Modified:Tue,18Apr201705:59:01GMT\r\n6.Howmanybytesofcontentarebeingreturnedtoyourbrowser?结果：返回到浏览器的内容的字节1267.Byinspectingtherawdatainthepacketcontentwindow,doyouseeanyheaderswithinthedatathatarenotdisplayedinthepacket-listingwindow?Ifso,nameone通过检查数据包内容窗口中的原始数据，您会看到任何标题在数据包列表窗口中未显示的数据中？如果是这样，找出一个。结果：没有。2.TheHTTPCONDITIONALGET/responseinteraction实验步骤：•Startupyourwebbrowser,andmakesureyourbrowser’scacheiscleared,as3discussedabove.•StartuptheEtherealpacketsniffer•EnterthefollowingURLintoyourbrowser•QuicklyenterthesameURLintoyourbrowseragain(orsimplyselecttherefreshbuttononyourbrowser)•StopEtherealpacketcapture,andenter“http”inthedisplay-filter-specificationwindow,sothatonlycapturedHTTPmessageswillbedisplayedlaterinthepacket-listingwindow.•(Note:IfyouareunabletorunEtherealonalivenetworkconnection,youcanusethehttp-ethereal-trace-2packettracetoanswerthequestionsbelow;seefootnote1.Thistracefilewasgatheredwhileperformingthestepsaboveononeoftheauthor’scomputers.)实验结果：8.InspectthecontentsofthefirstHTTPGETrequestfromyourbrowsertotheserver.Doyouseean“IF-MODIFIED-SINCE”lineintheHTTPGET?结果：第一次HTTPGET没有看到“IF-MODIFIED-SINCE”9.Inspectthecontentsoftheserverresponse.Didtheserverexplicitlyreturnthecontentsofthefile?Howcanyoutell?检查服务器响应的内容。服务器是否显式返回文件的内容？你怎么知道？结果：返回内容：410.NowinspectthecontentsofthesecondHTTPGETrequestfromyourbrowsertotheserver.Doyouseean“IF-MODIFIED-SINCE:”lineintheHTTPGET?Ifso,whatinformationfollowsthe“IF-MODIFIED-SINCE:”header?客户端第二次请求此URL时，根据HTTP协议的规定，浏览器会向服务器传送If-Modified-Since报头结果：有“IF-MODIFIED-SINCE:”，内容是：If-Modified-Since:Sat,22Apr201705:59:01GMT\r\n11.WhatistheHTTPstatuscodeandphrasereturnedfromtheserverinresponsetothissecondHTTPGET?Didtheserverexplicitlyreturnthecontentsofthefile?Explain.答案：状态码和相应状态信息的值为302MovedTemporarily。代表的意思是新的URL应该被视为临时性的替代。3.RetrievingLongDocuments5实验步骤：•Startupyourwebbrowser,andmakesureyourbrowser’scacheiscleared,asdiscussedabove.•StartuptheEtherealpacketsniffer•EnterthefollowingURLintoyourbrowser•StopEtherealpacketcapture,andenter“http”inthedisplay-filter-specificationwindow,sothatonlycapturedHTTPmessageswillbedisplayed.•(Note:IfyouareunabletorunEtherealonalivenetworkconnection,youcanusethehttp-ethereal-trace-3packettracetoanswerthequestionsbelow;seefootnote1.Thistracefilewasgatheredwhileperformingthestepsaboveononeoftheauthor’scomputers.)实验结果：12.HowmanyHTTPGETrequestmessagesweresentbyyourbrowser?结果：2个GET请求13.Howmanydata-containingTCPsegmentswereneededtocarrythesingleHTTPresponse?需要多少数据包含TCP片段来承载单个HTTP响应？结果：4个14.WhatisthestatuscodeandphraseassociatedwiththeresponsetotheHTTPGETrequest?答案：状态码和短语是200OK：表示请求成功，信息包含在响应的报文中。615.ArethereanyHTTPstatuslinesinthetransmitteddataassociatedwithaTCPinduced“Continuation”?结果：有，对于一个大的HTML文件会被TCP分为若干个独立的包。4.HTMLDocumentswithEmbeddedObjects实验步骤：•Startupyourwebbrowser,andmakesureyourbrowser’scacheiscleared,asdiscussedabove.•StartuptheEtherealpacketsniffer•EnterthefollowingURLintoyourbrowser’slogoisretrievedfromthe’scoverisstoredatthemanic.cs.umass.eduserver.•StopEtherealpacketcapture,andenter“http”inthedisplay-filter-specificationwindow,sothatonlycapturedHTTPmessageswillbedisplayed.•(Note:IfyouareunabletorunEt