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Use of the Devices. Justin Champion Room C208 - Tel: 3273 www.staffs.ac.uk/personal/engineering_and_technology/jjc1. Using the data device. Contents Why use the methods WAP I-mode Benefits of them Problems with them. Using the data device. Internet
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Use of the Devices Justin Champion Room C208 - Tel: 3273 www.staffs.ac.uk/personal/engineering_and_technology/jjc1
Using the data device • Contents • Why use the methods • WAP • I-mode • Benefits of them • Problems with them
Using the data device • Internet • The ability to display information on the Internet is its most widely used feature • World Wide Web (WWW) pages • Hyper Text Mark-up Language (HTML) • eXtended Mark-up Language (XML) • Math Mark-up Language (MathML) • Java • Java Applets • Plug ins • Extend the capabilities • Assumes • A standard monitor (display size) • Performance of the machine • Audio support • Storage • Interactions
Using the data device • Money • To charge user to receive data a method must be used to provide information to the user • The methods available for portable devices are • WAP • I-Mode • Java2Me • HTML – New 3 and 2.5 G devices
Using the data device • These protocols are higher level in the OSI network stack • Telling us that • They are independent of the technology that transfers and displays them • The receiving device just needs to have the knowledge of how to deal with the data • Newer devices with OS’s that are updatable can just download new technologies as it becomes available • If HTML is upgraded no need to replace the device
Using the data device • Wireless Application Protocol • Widely pushed in Europe for use with GSM devices “Surf the net surf the BT Cellnet” • Developed as a standard and controlled by the WAP forum • www.wapforum.org • Intended to bring together developments which several manufacturers were working on. • They all recognised a requirement to present information on mobile devices • Motorola, Nokia, Siemens, Erricson and more • Based on thin client technology with the server doing all of the work • WAP is a set of different protocols for communications
Using the data device • WAP Continued • A number of parts need adding to the network to allow WAP • WAP aware handsets • WAP Gateway • Versions • 1.0 - 1998 • 1.1 - 1999 • 1.2 – 1999 • 2.0 - 2001
Using the data device • WAP Requirements • Non-proprietary • Interoperable • Scalable • Efficient • Reliable • Secure • WAP protocol stack was designed to be secure from day one
Using the data device • WAP Continued • Infrastructure Filter WAP Gateway Phone Network Internet HTML Server BS BS WML Server
Using the data device • WAP Continued • A device makes a request for a webpage from the Internet • Request is sent to the WAP Gateway • The gateway then makes this request from the Internet server • If the server has content which is WAP enabled then this is returned • Obviously as the content has been written for a WAP device • If the webpage is only available in HTML this is converted by the WAP gateway into WML • The WAP gateway compresses the content and this is returned to the requesting device • This allows for less bandwidth and time for the transmission
Using the data device • WAP continued • Example of WML • WML uses the concept of a deck of cards • The entire deck is loaded into the device at once • Each of these cards are then called • This demo is taken from a tutorial on the Internet (http://www.zvon.org/xxl/WMLTutorial/Examples/Example1/index.html, 2004) <?xml version="1.0"?><!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" "http://www.wapforum.org/DTD/wml_1.1.xml"><wml> <card><br/> <p><b><i>Miloslav Nic</i></b></p> <p><strong>Introduction to WML.</strong></p> <do label='Click to visit other Zvon tutorials (XML,XSL,CSS,Perl,...)' type='accept'><go href='http://www.zvon.org/ZvonHTML/Zvon/zvonTutorials_en'/></do> </card> </wml>
Application Layer (WAE) Session Layer (WSP) Transaction Layer (WTP) Security Layer (WTLS) Transport Layer (WDP) Using the data device • WAP Continued • Stack • WAE • Allows the interpretation of WML • Allows interaction with any application • WSP • Allows the storing of session information, rather than creating new session for each packet. Allows connection orientated and connectionless services • WTP • Allows the messages to be brought together and presented to the WSP layer • Three classes • 0 - unreliable • 1- reliable with automated acknowledgements • 2 – reliable, request response • WTLS • This is similar to the SSL used on the internet for secure communications • WDP • This is the transport protocol the data is encapsulated into
Using the data device • WAP • WAE • Application environment • User agents are runs at this level • Allowing any software to use WAP • The most common is a user agent which interprets WML and display • Could be just as easy a client server environment, with a front end to the server
Using the data device • WAP Continued • Infrastructure • WAP Gateway • Acts as a firewall to the network • Acts as a proxy to get the web pages • Translation can be carried out on pages which are based on HTML content • Data will be compressed if required • Binary encoding
Using the data device • WAP Continued • Usage • WAP is increasingly used on phones • Not for displaying information but for downloading ring tones • 30 Million hits per day in September, 2003 • www.text.it/wap/default.asp?intPageId=580 • WAP got bad press when it was first launched as a information service • Service was slow and unreliable • A lot of the blame for this lay with the service providers not the technology • A connection has to be made each time you start a WAP session, this does take time • Expensive to use • The business model used charges you for the time you view a page • Original images were sent as Wireless BMP (WBMP) • In version 1.1 these images are black and white only
Using the data device • WAP Continued • Will also increase its usage as interfaces improve • It was difficult with older phones to select what you wanted • Even harder to type it ! • New device use touch screen technology • Virtual keyboards onboard • These will allow a better HCI experience
Using the data device • WAP Usage • WAP is not WML • WML is just one use of the WAP stack • WAP is intended to be a transport protocol for mobile devices • Available on all networks • Not specific to GSM • Most commonly used to view WML pages • There is a user agent installed on the device to display the WML data • WML data can be compressed into binary XML, to decrease the amount of time required for transmission
Using the data device • i-Mode • Developed and owned by a single company • NTT DoCoMo (translated to “Anywhere”) • I in i-mode is “information” • Launched in Japan in 1999 • Only available in the Japanese market • This is changing with European and American companies considering using it now • Based on the premise that you only pay for the data you receive (like GPRS)
Using the data device • i-Mode • Was developed to allow extra revenue for NTT • They required the money to update there old telecommunication infrastructure, similar to GPRS • Created by Mari Matsunaga • She had no background in computing or telecommunications • She was a magazine editor by training! • Is a service portal and not a protocol • Owned and run by NTT and only subscribers can use these services • Gives a monopoly to NTT • It is not a open standard, but devices showing the i-mode symbol are capable of connecting to the portal
Using the data device • i-Mode • Based on a packet based service • Uses the NTT Personal digital cellular (PDC) infrastructure • This is similar to GSM • Based on TDMA • Voice and data are transmitted using packets • Operates at 800Mhz and 1500Mhz frequencies • Transmission speeds are • 5.6 kbps and 9.6 kbps
Using the data device • i-Mode infrastructure packet based i-MODE Server M-SCP PGW M-PGW PPM BS BS Internet
Using the data device • i-Mode Infrastructure parts explained • Mobile Station (MS) • The actual communicating device • Base station (BS) • Base station, allow the transmission and receipt of packets over the air interface • Packet Processing Module (PPM) • This part is responsible for the management of the packets sent to and received by the MS • Packet Gateway Module (PGW) • Provides the functionality to connect to other packet switched networks • Internet • Private LANS • Other public packet switched networks
Using the data device • i-Mode Infrastructure parts explained • Mobile Message Packet Gateway Module (M-PGW) • This device is responsible for the terminating of communications with the device • i-MODE uses a different transport protocol inside the network to reduce the overhead from the usual TCP. This is Transfer Layer Protocol (TLP) • TLP increases the ratio of data to header and reduces the amount of delivery receipts sent • The M-PGW handles the conversion between the packet types for coming in or and gong to the Internet • Mobile Service Control Point (M-SCP) • Authenticates and approves packet communications to the device • i-MODE server • Either supplies the data from the local servers or connects to the internet to gain the required pages
Using the data device • i-Mode very successful • The use of I-Mode is not only successful but profitable • The end user pays a monthly subscription • Services are offered which require additional payment • News services • Football results • Ticket ordering • NTT • Take commission for on-line sales of about 10% • The user pays for receiving the data per packet (128 bytes) • Slow connection speeds max 9.6 Kbps
Using the data device • Logic dictates it should fail • Why does it not • The main issue is that the amounts charged are small • Micro Payments • This means that the end user does not notice how much they are spending • 600 packets of data is £1 • Monthly subscription is £1 • These little and often charges do not offend users as once they have downloaded a page they view it there leisure • Unlike WAP • Japanese language does not have spaces, so not a problem with words that will not fit onto the line wrapping to the next • Usage • 60% of worldwide mobile internet users use i-MODE • 39% use WAP • marketed from day 1 at the youth market, WAP was initially pushed at the business market
Using the data device • i-Mode technology • 9.6 Kbps data rate • Always uses Compact HTML (cHTML) as the display format • Supports colour GIF images • “cHTML is defined so that all basic operations can be done by a combination of four buttons: Cursor Forward, Cursor Backward, Select, and Back/Stop (return to the previous page). Any functions that require two- dimensional focus pointing, like image map and table, are excluded from cHTML” (Extract from the cHTML submission to the W3C. For details of cHTML, access http://w3.org/TR/1998/NOTE-compactHTML-19980209.)”
Using the data device • cHTML • Is fully complaint with internet HTML • The conversion takes place transparently at the application layer • Features will be removed like • Tables, jpg images, fonts and styles • Advantage of this is any ‘normal’ web server can provide content for i-MODE • Web page size limit is 5KB, but this may change in the future • Mail messages are also limited to 500 bytes • The excess is just thrown away! • cHTML is NOT a Internet standard, it has been submitted but not approved
Using the data device • Link • If you wish to try out WAP • http://www.yospace.com/spedemo.html • Links to the LIVE WAP Network
Using the data device • Summary • Why not use HTML • WAP • Software • Hardware • I-Mode • Software • Infrastructure