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Use of the Devices Justin Champion Room C208 - Tel: 3273 www.staffs.ac.uk/personal/engineering_and_technology/jjc1
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Using the data device Contents Why use the methods WAP I-mode Benefits of them Problems with them
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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
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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
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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
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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 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
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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
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Using the data device WAP Requirements Non-proprietary Interoperable Scalable Efficient Reliable Secure WAP protocol stack was designed to be secure from day one
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Using the data device WAP Continued Infrastructure BS Phone Network BS WAP Gateway Internet WML Server HTML Server Filter
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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
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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)http://www.zvon.org/xxl/WMLTutorial/Examples/Example1/index.html Miloslav Nic Introduction to WML. Miloslav Nic Introduction to WML.
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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 Transport Layer (WDP) Security Layer (WTLS) Transaction Layer (WTP) Session Layer (WSP) Application Layer (WAE)
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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
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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
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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 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
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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
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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
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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)
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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
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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
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Using the data device i-Mode infrastructure packet based BS PPM BS PGWM-SCPM-PGW i-MODE Server Internet
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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
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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
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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
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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
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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.)” http://w3.org/TR/1998/NOTE-compactHTML-19980209
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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
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Using the data device Link If you wish to try out WAP http://www.yospace.com/spedemo.html Links to the LIVE WAP Network
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Using the data device Summary Why not use HTML WAP Software Hardware I-Mode Software Infrastructure
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