protocols for the w eb and the mobile Internet 1 November 2005
agenda � HTTP � History � Evolution � W@P � History � Architecture � WAP in the real world 1 November 2005
http history � 1992 : HTTP/0.9 � 1996 : HTTP/1.0 informational RFC 1945 � 2001 : HTTP/1.1 formal standard 1 November 2005
http overview � request-response type of protocol � stateless protocol � independent of data representation 1 November 2005
http evolution � HTTP/0.9 � only GET method defined for request messages � in the reply only HTML content is transmitted 1 November 2005
http evolution � HTTP/1.0 (1/2) � HTTP Request/Response � new message format introduced: structured multiline message including headers � appending the HTTP version in the request message � MIME type included 1 November 2005
http evolution � HTTP/1.0 (2/2) � new methods defined: HEAD, POST, PUT, DELETE, LINK, UPLINK � basic user authentication 1 November 2005
http evolution � HTTP/1.1 (1/2) � Request/Response message formats finalized Response = Status-Line Request = Request-Line *(( general-header *(( general-header | response-header | request-header | entity-header ) CRLF) | entity-header ) CRLF) CRLF CRLF [ message-body ] Status-Line = HTTP-Version SP [ message-body ] Status-Code SP Reason-Phrase CRLF Request-Line = Method SP Request-URI SP HTTP-Version CRLF 1 November 2005
http evolution � HTTP/1.1 (2/2) � Persistent connection added � New request methods:PUT, OPTIONS, TRACE & CONNECT � Headers: general-header, request-header, response-header and entity-header used to send information about the HTTP message � host header � Range, Content Range headers 1 November 2005
� HTTP and the Web in the future... 1 November 2005
w ireless application protocol � Why is it need? � The web gained enormous popularity � Mobile telecommunications matured � Next step: Internet anywhere anytime The web though is designed for desktops that have access to high bandwidth and reliable network connections WAP will provide for optimization for the wireless environment and will address its limitations 1 November 2005
w ap: challenges � Device constrains � Network constrains � Less powerful CPUs � Low bandwidth � Less memory � High network latency � Restricted power � Less connection consumption stability � Smaller displays � Less predictable availability � Different input devices (e.g a phone keypad, voice input, etc.) 1 November 2005
w ap history � 1997: WAP Forum established (Nokia, Ericsson and Motorola, Phone.com ) � 1998: WAP 1.0 � 2002: WAP 2.0 1 November 2005
w ap 1.0 � Objectives � To bring Internet content to the wireless terminals � To create a protocol specification that will work across different wireless network technologies � To enable the creation of content that scales across many wireless bearer networks and wireless device types � To extend existing standards wherever appropriate 1 November 2005
w ap 1.0 architecture � WAP 1.0 Programming model fig.WAP 1.0 Programming Model [2] 1 November 2005
w ap 1.0 architecture � WAP 1.0 Protocol Stack fig. WAP 1.0 Components [2] 1 November 2005
w ap in the real w orld � Massive publicity started well before WAP was available. Marketed as the next Internet revolution � First WAP services launched in 1999 (Sonera the first operator to provide wap services) 1 November 2005
w ap in the real w orld � Usability issues � Usability studies � Difficult to configure. over-the-air configuration available � Transactions(browsing) are really slow � Service is expensive 1 November 2005
w ap in the real w orld � ”Broken promisses or wrong expectations” � The killer application never materialize � Not so many WAP resources available 1 November 2005
w ap 2.0 � Objectives � Add support for the standard Internet protocols � Continues to work on the goals set by WAP 1.0 1 November 2005
w ap 2.0 architecture � WAP 2.0 Programming model WAP 2.0 Programing Model [3] 1 November 2005
w ap 2.0 architecture � WAP 2.0 Legacy Protocol Layers WAP 2.0 Components [3] 1 November 2005
w ap 2.0 architecture � WAP 2.0 Protocol layers for IP support WAP 2.0 with support for standard Internet protocols [3] 1 November 2005
w ap 2.0 architecture � WAP 2.0 Components � Wireless Profiled HTTP � Transport Layer Security � Wireless Profiled TCP 1 November 2005
the competitor � i-mode � A proprietary service (owned by NTT DoCoMo) � Can practically read any Web page � i-mode uses compact HTML (cHTML) which is practically subset of HTML with some I-mode specific tags � Packets-witched � Charging based on transfer not air time.WAP initially used circuit switching 1 November 2005
i-mode � “If i-mode was a superior specification or technology, then other companies would have adopted it by now. But 500-and-some companies have gotten behind the WAP standard rather than the I-mode standard. That's got to tell you something.” , article 2000 WAP or I-Mode: Which Is Better?, www.wired.com � the service is expanding globally since 2002 � Available in Germany, Taiwan, The Netherlands, Belgium, France, Italy, Greece, Australia, Israel, Russia , United Kingdom and Ireland 1 November 2005
� The future of wap... 1 November 2005
references � Hypertext Transfer Protocol – HTTP/1.1 , Standard Track � Wireless Application protocol White Paper At http://www.wapforum.org/what/WAP_whitepages.pdf � Wireless Application Protocol WAP2.0 Technical White Paper At http://www.wapforum.org/what/WAPWhite_Paper1.pdf � WAP Field Study Findings At http://www.useit.com/alertbox/20001210.html � WAP: Broken Promises or Wrong Expectation? , The Internet Protocol Journal, Volume 6, Number 2, June 2003. Available at www.cisco.com 1 November 2005
references � The unofficial independent imode FAQ At http://www.eurotechnology.com/imode/faq.html � I-mode , At www.nttdocomo.com � Content Networking in the Mobile Internet, Sudhir Dixit and Tao Wu, ISBN: 0-471-46618-2 1 November 2005
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