-
9 DNSTelnetE-mailFTPWWW*
-
9.1 DNSwww.xjtu.edu.cnIP202.117.0.2032 TCP/IPIPIPDomain Name
SystemDNSName ResolutionMAC12-FA-9B-23-DB-1148/ IPMACARPDNSRFC
1035TCP/IPUDP53
-
IPIPIPIPIPwwwFTPIPIP
-
root
com net org edu gov mil int cn uk hk ...
ibm hp intl 3com
com edu gov net
tsinghua pku sjtu fudan xjtu
www mail ftp bbs
-
.63255www.xjtu.edu.cnnetcourse.xjtu.edu.cnxjtu.edu.cn
-
DNSDNSDNSDNSDNSDNSDNSDNSIPDNS202.117.0.20xjtu.edu.cnIPDNSDNSDNS202.117.0.21
-
DNSLocal Name Server/DNSRoot Name ServerAuthoritative Name
ServerDNSDNS
-
DNSDNSDNSDNSDNSDNS DNSDNSDNSDNSDNSDNS
-
Awww.xjtu.edu.cnxjtuIPADNS1DNS1xjtuJDIPADNS1xjtuDNS1cnBIPDNS1DNS1Bedu.cnDNSCDNS1Cxjtu.edu.cnDNSDDNS1Dwww.xjtu.edu.cnIPnslookupDNS
-
AAddress A IP NSName ServerDNS CNAME WWWFTPMAIL[]MXMail
Exchanger[]PTR DNS202.117.0.20PTRSOADNSabc.mydomain.comA
WWWMAILCNAMEWWWMAIL
www.mydomain.commail.mydomain.comabc.mydomain.comInternet
[email protected] DNSmail.mydomain.comMXDNSMX MX
-
DNSRRs
-
DNSARPDNS()IP()ARP IP() MAC() DNSARPLANDNSARPLAN
-
9.2 TelnetTelnetTelnetTelecommunication Network
ProtocolIPUNIX
-
Telnet Server Username:Password:
InternetTelnet
-
TelnetTelnetClient/ServerTCPTelnetTCPTCP,TelnetTelnetTCP
-
Telnettelnettelnet [remote-system] [port-number]telnet
NVT220remote-system()IPport-number telnet telnet23telnet
telnet>
-
UNIX $telnet www.xjtu.edu.cn $telnet 202.117.35.70 IP
$telnettelnettelnet> open telnet>open www.xjtu.edu.cn
telnet>open 202.117.35.70
-
login passwordemaillynxpicolspwdexitlogoutCtrl-D
-
9.3 E-mail90User AgentOutlookOutlook ExpressFoxmail
-
E-mail Server/SMTPSimple Mail Transfer Protocol[RFC
821822]MIMEMultipurpose Internet Mail Extension[RFC 1521]POP3Post
Office Protocol[RFC 1939]IMAP4Internet Message Access Protocol[RFC
2060]
-
TCPTCPTCPTCP SMTPTCP SMTPSMTPSMTP TCP POP3 SMTP
Cloud
Processor
Minicomputer
Workstation
Internet
E-mail Server
E-mail Server
User Agent
SMTP
SMTP
User Agent
POP3
OutlookFoxMail
OutlookFoxMail
-
@ @[email protected]@xaonline.com
-
SMTPSMTPTCPSMTP25TCPSMTPRFC821RFC822SMTP7ASCIISMTP
-
[RFC822]headerbody
-
Received: from web10905.mail.yahoo.com (unknown
[216.136.131.41])by 192.168.30.102 (Coremail) with SMTP id
XQEAACPEeD3FAIMp.1for ; Fri, 06 Sep 2004 23:05:16 +0800
(CST)Message-ID: Received: from [67.242.159.232] by
web10905.mail.yahoo.com via HTTP; Fri, 06 Sep 2004 08:11:04
PDTDate: Fri, 6 Sep 2004 08:11:04 -0700 (PDT)From: Joy Li Subject:
ThanksTo: ChenWenge Cc: [email protected]:
MIME-Version: 1.0Content-Type: text/plain; charset=us-ascii
012345678 21
-
Received From DateMessage-ID To SubjectContent-typeMIME CcCarbon
copy
-
SMTPSMTP/SMTPSMTPHELOMAIL FROMRCPT TODATAQUIT
-
TelnetSMTP $ Telnet mail.xjtu.edu.cn 25 Trying 202.117.1.21...
Connected to mail.xjtu.edu.cn. Escape character is '^]'. 220 ESMTP
ready [202.117.35.70/unknown] HELO 250 MAIL FROM 250 OK RCPT TO 250
OK DATA 354 go ahead This is a test message. Be sure is send by
Telnet. . 250 OKhas queued QUIT 221 close connection Connection
closed by foreign host. TCPSMTP//email25
-
SMTPMessageASCIIMIMEASCII
-
E-mailUU(Unix-to-Unix Encoding) UnixDOSASCIIUUMIME(Multipurpose
Internet Mail Extensions)
MIMEInternetMIMEBase64QP(Quote-Printable)QP787QPASCII,QP16=QP=A4j=AEa=A6n=A1I=A7=DA=AC0=B1=E7=A9s=A7g=A1A=AB=DC=B0Base647
Base64pGquYaZuoUmn2qxPseepc6dnoUGr3LCqv70msMIMEEmailQPBase64 Binhex
BinhexAppleMacPC
-
POP3IMAPPOP3TCP/Outlook ExpressFoxmailExchangeTCPPOP
-
IMAPTCPPOP3/POP3IMAPIMAPWeb Mail
-
Outlook ExpressOutlook
-
Outlook Express.emlOutlookExcelOutlookOEExcel
-
Outlook Express
-
9.4 FTPFTPFTPFile Transfer
ProtocolUploadPutDownloadGetFTPASCIIBinaryFTPFTPAnonymous
-
Software ProgramDocumentsVideoAudioftp ftp.xjtu.edu.cnUsername:
anonymousPassword: [email protected] FTP
Serverftp.xjtu.edu.cn
-
FTPFTPTCPTCPFTP/FTPCuteftpFTPServ-U
-
FTPTCPControl ConnectionFTP21,FTPFTPData ConnectionFTP20FTP
-
TCPFTPTCPFTPX2120Y
-
FTP1 TCP SYNTCP21 2SYN ACK213ACKFTPFTP
-
PORTPORT 1SYN20PORT2SYN ACK20 3ACK
-
1FIN2ACK3FIN4ACK FTP1FIN2ACK3FIN4ACK
-
ftp Client ftp Server TCP:21 , SYN Port xxxx
----------------------> Port 21 SYN, ACK Port xxxx Port 21
: Port, IP, Port yyyy Port xxxx ----------------------> Port
21 Port Successful Port xxxx Port 21
TCP:20 , SYN Port yyyy Port 20 ACK Port yyyy
-
FTPFTPFTP [host] %ftp ftp.xjtu.edu.cn ftp>open
ftp.xjtu.edu.cn usernamecw024001001 password******
usernameanonymous [email protected]
-
1ftpftp>?ftp>helpftpopenftp>help open2ftp>open host
ftp>close ftpftp>disconnect ftpftp>bye ftpftp>quit
ftp
-
3ftp>pwd ftp>cd ftp>cdup ftp>ls [remote-dir]
[local-file] ftp>mls remote-file local-file txtdirfile.list
ftp>mls *.txt dirfile.listftp>nlist - [remote-dir]
[local-file] rtrcftp>nlist -rt /disk1/test test.list
-
4ftp>put local-file [remote-file] ftp>send local-file
[remote-file]ftp>append local-file [remote-file]ftp>mput
local-file ftp>get [local-file] remote-fileftp>recv
[local-file] remote-fileftp>reget [local-file] remote-file
getftp>mget remote-file
-
FTP ClientFTP Serverput mputget mgetrecv regetsend append
-
5ftp>ascii ftp>binary 6ftp>chmod mode remote-file
modeftp>chmod 666 aa 7ftp>get filename
-filename-8renamedeletemdeletesize
-
FTP[01]~[15] [01] ftp ftp.xjtu.edu.cn[02] Connected to
vineyard.xjtu.edu.cn.[03] 220 vineyard.xjtu.edu.cn FTP server
(Version wu-2.5.0(1) Tue Jul 13 10:20:43 CDT.[04] Name
(ftp.xjtu.edu.cn:teng): anonymous[05] 331 Guest login ok, send your
complete e-mail address as password.[06] Password:
[email protected][07] 230 Guest login ok, access restrictions
apply.[08] ftp>cd /pub/rfc[09] 250 CWD command successful.[10]
ftp>get rfc959.txt ftpinfo[11] 200 PORT command successful.[12]
150 Opening ASCII mode data connection for rfc959.txt (147316
bytes).[13] 226 Transfer complete. local: ftpinfo remote:
rfc959.txt 151249 bytes received in 2.1 seconds (71.27
Kbytes/s)[14] ftp>quit[15] 221-You have transferred 151249 bytes
in 1 files. 221-Total traffic for this session was 152964 bytes in
1 transfers. 221-Thank you for using the FTP service on
vineyard.xjtu.edu.cn. 221 Goodbye.
-
[01] FTPFTPFTPftp.xjtu.edu.cn[02] FTP[03] 220[04]
FTPanonymousFTP[05] [06] [email protected][07]
230[08]ftp>FTPhelp,dircdRFC[09] CWDChange Working Directory[10]
rfc959.txtftpinfo[11] PORT200[12] 150[13] 226[14] [15] FTP
-
FTPWindowsFTPFTP WS_FTP CuteFTP LeapFTP LeechFTP FTP
202.117.35.70 k1010anonymous xxxx abc@edf c:\ /home/k1010 /pub
-
FTPFTPWindowsFTPWS_FTPCuteFTPLeapFTPLeechFTP FTP IP anonymous
xxxxxx [email protected]
-
FTP(cuteftp)
-
4.4 FTP
-
4.5 WWWBrowserWebWebWebWeb
-
HypertextLink)Hyperlink)Hypermedia
-
WebWebAPACHE (Hypertext Markup LanguageHTML)WebWebHypertext
Transport ProtocolHTTPWeb
-
WWWHTTPHTTP
-
HTTPClient/ServerHTTPHTTPURL
-
HTTP(content-type)HTTPHTTP
-
HTTPHTTP
-
HTTP(Meta Information)HTTPHTTP
-
http : request http messages: request, responsehttp request
message:ASCII ()GET /somedir/page.html HTTP/1.0 User-agent:
Mozilla/4.0 Accept: text/html,
image/gif,image/jpegAccept-language:fr
(extra carriage return, line feed) request line(GET, POST, HEAD
commands)header linesCarriage return, line feed indicates end of
message
-
http request message: general format
-
http: responseHTTP/1.0 200 OK Date: Thu, 06 Aug 1998 12:00:15
GMT Server: Apache/1.3.0 (Unix) Last-Modified: Mon, 22 Jun 1998 ...
Content-Length: 6821 Content-Type: text/html data data data data
data ... status line(protocolstatus codestatus phrase)header
linesdata, e.g., requestedhtml file
-
http 200 OKrequest succeeded, requested object later in this
message301 Moved Permanentlyrequested object moved, new location
specified later in this message (Location:)400 Bad Requestrequest
message not understood by server404 Not Foundrequested document not
found on this server505 HTTP Version Not SupportedIn first line in
server->client response message.A few sample codes:
-
Trying out http (client side) for yourself1. Telnet to your
favorite Web serverOpens TCP connection to port 80(default http
server port) at www.eurecom.fr.Anything typed in sent to port 80 at
202.117.35.70telnet 202.117.35.70 802. Type in a GET http
requestGET /~k1010/hello.html HTTP/1.0By typing this in (hit
carriagereturn twice), you sendthis minimal (but complete) GET
request to http server3. Look at response message sent by http
server!
-
Conditional GETClienthttp requestIf-modified-since:
ServerHTTP/1.0 304 Not Modifiedclientserverhttp request
msgIf-modified-since: object not modifiedhttp request
msgIf-modified-since: http responseHTTP/1.1 200 OK
object modified
-
URL
-
Uniform Resource Locator URL
WebWebhttp://www.xjtu.edu.cn/index.htmURL URL
-
http:// ftp:// gopher:// telnet:// news: mailto:
-
jpg/
-
/
-
()
-
*URLURLWebBookmarkHotlist)Web
-
Web Caches (proxy server)web cachewebhttp requestsweb cacheweb
cacheweb cacheweb cacheclientProxyserverclienthttp requesthttp
requesthttp responsehttp responsehttp requesthttp responseorigin
server
-
HTML HTMLHypertext Markup Language(tag)HTML(element)(start
tag)(end tag)
-
HTMLHTML HTMLHTML(DHTMLASPPHPJAVA Script)HTML
-
HTML Test
-
HTML
HTML
Describing the appearance and contents of a page
-
HTML ()
rosessunflowersdaffodils
-
HTML ()
I am having funAre you having fun too?
applesorangesmangoes
-
JanuaryFebruaryMarch 12562957256
-
HTMLHEADBODYHTMLHTML.htm.html HEAD BODYHTML
-
HTML
-
*4.6 loss tolerant:Streaming stored audio and video Streaming
live audio and videoReal-time interactive video
- Streaming stored MM (VCR: pause, resume, fast forward, rewind,
etc.): 110Unidirectional Real-Time: Interactive Real-Time :Video:
< 150 msec acceptableAudio: < 150 msec good,
-
TCP/UDP/IP(best-effort service) 5-10Real-Time Interactive packet
jitter
-
Streaming Stored Audio & VideoStreaming stored
media:Audio/video audio/videoAudio/video Media player:
-
Streaming from Web server (1)AudiovideoWeb server HTTP Web
serverHTTP content-type header line audio/videoBmedia playermedia
playermedia player : Web
-
Streaming from Web server (2) Web meta file Content-type header
audio/video TCPHTTP Some concernsHTTPUDP
-
Streaming from a streaming serverHTTPTCP/UDP
-
TelnetFTPE-mialWWW*
***************************************************************************************************
