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Wireless Communication Understand the trend of wireless communication Understand WAP protocol, PCS, GSM and CDMA Understand the power of combining mobile communication with the Internet called Mobile Internet. Terminologies
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Wireless Communication Understand the trend of wireless communication Understand WAP protocol, PCS, GSM and CDMA Understand the power of combining mobile communication with the Internet called Mobile Internet.
Terminologies • 3G, "3rd generation",, generally applied to wideband mobile services and applications. • 3GPP, Third Generation Partnership Project,, set up to speedup the development of open globally-accepted technical specifications for G. • Bluetooth, A global initiative by Ericsson,, IBM,, Intel,, Nokia and Toshiba to set a standard for cable-free connectivity between mobile hones,, mobile PCs,, hand held computers and other peripherals.
Terminology • CDMA, Code Division Multiple Access. The code division technology was originally developed for military use over 30 years ago. CDMA is a multiple access technique,, which uses code sequences as traffic channels within common radio channels - used for CDMA One (IS-95) air interface. • EDGE, Enhanced Data rates for GSM Evolution. EDGE has been developed for those networks that didn't but a UMTS license and while it promises only about a third of the bandwidth
Terminology • GPRS, General Packet Radio Systems. GPRS is hailed as the 2.5 for mobile phones and will be with us from the beginning of 2001. GPRS will give you a permanent connection at about 50 kbps or so to your mobile phone. • GSM, Short for Global system for Mobile Communications,, it is the mobile phone platform used in Europe,, Hong Kong and much of the rest of the world. However,, it is not mainstream in the USA. Dual band phones are capable of operating on other bandwidths aboard.
Terminology • iMode, Japanese network NTT DoCoMo has had a great deal of success with iMode,, with the main advantage over WAP being that it is packet-switched network. • UMTS, Universal Mobile Telephony System. This is almost universally subscribed to standard for the third generation and is generally based on W-CDMA (Wideband Code Division Multiple Access) telephony students. It promises a permanent internet connection of at least 384kbps and up to about 2mbps,,
Terminology • WAP, Wireless Application Protocol. The development of WAP is being driven by the WAP Forum,, initially founded by Motorola
Digital Television • The television signals that we are using are analogous, not digital. Digital TV not just the change of signal transmission format, but also the interactivity between the TV set and audience. • Cost and Benefitthere are cheaper ways to get a picture as good as digital as within the 100hz screen technology costing around US900+, • That is similar to the real Dolby Digital sound that we hear in DVD machines.
Components • To receive ONDigital Terrestrial TV (BBC-ITV), there is a need to install a set top box connected to the existing TV. • To receive Sky Digital satellite TV, Old and new customers will need a brand New Satellite Dish & Decoder. The box will also have to be connected to the telephone socket • To receive Digital cable services, we need a new digital set top box which will also be upgraded automatically to old customers from the local telephone company.
Set Top box • Set Top box is needed, as the boxes are being made by Nokia, Phillips, Toshiba, Sony & Pace, with another new contract just being signed by Northern Telecom and Cable & Wireless for Pace to supply their home set top boxes for the coming summer 2000 launch for Digital Cable.
PCS • Personal Communications Services, a whole family of next-generation wireless communications services that include new categories of wireless voice, two-way messaging and high-speed data transmission using lightweight, multi-function, • PCS networks operate similarly to other radio technologies in that signals are sent using a series of transmitters (also called base stations) mounted on buildings, free-standing towers and other structures. • PCS phones send and receive digital signals via these base stations and a system of computerized switches.
GSM • The "Global System for Mobile Communications" or GSM is an international digital radio standard created by the European Telecommunications Standards Institute (ETSI). PCS network uses GSM technology.
Wireless Application Protocol • Wireless Application Protocol (WAP) provides a universal open standard for bringing internet content and advanced value added services to mobile phones and other wireless devices. It is the platform for a new generation of "media phones" which will enable users to easily access web based interactive information services and applications from the screens of their mobile phones.
The Need • WAP gives mobile access to information and services for small wireless devices as i.e. mobile phones and PDAs. • WAP takes care of the limitations those kinds of devices have and the demand of flexibility they need.
The Limitations • Small display screens with low resolution. • The input devices have limited capacity and mostly no pointing device • Low power CPU, less memory and less reliable power supply. • The network offers less bandwidth and less reliable contact.
The Flexibility • When it is compared to i.e. HTML-C, the WAP-standard does not specify how a WAP-device should look like.
Importance • It is important because the combination of mobile phone and the Internet is the trend. WAP is the standard for this.
The operation • The WAP standard was created because the world's leading companies in the business of telecommunication saw the need for a global standard for wireless communication with extended services on a small handheld device. • WAP combines two techniques; wireless communication and the Internet.
WAP architecture • Application Layer • It is based on a combination of Mobile Telephony and World Wide Web technologies. and consist of the following • Session layer • Wireless Session Protocol (WSP) This layer offers mainly two session services; connection session and connectionless session. • Transaction Layer • It provides a light-weight transaction-oriented protocol that is suitable for mobile clients.
WAP architecture • Security Layer • It is based on the industry-standard TLS (Transport Layer Security) protocol, • It can be used for secure communication between terminals and business cards. • Transport Layer • It operates above the data capable bearer services and offers a consistent service to the upper layer protocols in the WAP • Network Layer • It is the Wireless bearers and is designed to operate over a variety of bearer services, like SMS, CDMA, CSD and more.
WAP Gateway • The WAP Gateway is a device for converting the TCP/IP protocols to the different WAP protocols and vice versa. It is able to translate HTML to WML.
Wireless Markup Language • WML (Wireless Markup Language) is similar to HTML and is used to create pages to be shown in a WAP-browser. A WAP-browser is always included in a WAP-device.
WAP-browser • A WAP-browser (WAP micro-browser) interprets WML in a WAP-device. It is similar to a web browser in a PC.
WMLScript • WMLScript is similar to JavaScript but there are also differences. • WMLScript is precompiled, as WML is, before it reaches the wireless device. WML contains no WMLScripts, only references to WMLScript URLs. • WAP version 1.2 has now been approved. This version introduces WAP Push Architecture, user agent profiles (UAPROF), WDP-tunling,.
Use of PC to test WAP • We can use PC to test WAP, but cannot use an ordinary web-browser to view a WAP-site. To be able to access a WAP-site through Internet, we need a WAP-emulator in PC. You can try the following URLs.http://wap.combra.se/The Nokia WAP Toolkit 1.1 is downloadable from http://www.forum.nokia.com/developers/wap/wap.htmlEricsson has a similar SDK, downloadable from http://mobileinternet.ericsson.se/emi/Dynamical Systems Research offers a commercial development environment, read more at http://www.wap.net/devkit/Slob-Trot Software has the WML-browser WinWAP, downloadable at http://www.slobtrot.com/winwap/
secure transactions using WAP • WAP 1.1 has a security-layer, in the protocol stack, named WTLS handling the security. A strongly secure solution should be built using an WAP-server connected directly to the GSM-network. Security is not though something that comes automatically and applications demanding a high level of security must be developed with great care.
Conversion from HTML to WML • There are systems for automatic conversion from HTML to WML. How well this works in reality depends on the device, the application and the complexity of the HTML-page to convert.
HTML-C • This is a variant of HTML with some added tags to make it usable on a cellular like wap-device. NTT Docomo, the biggest cellular phone operator, has used it in Japan since 1999. Many people see this as a first step towards WAP.
HDML (Handheld Device Markup Language) • has been available since 1996. It is developed by Phone.com, which also is one of the promoters to WAP. In USA HDML is more common than WAP so far, because HDML came first. A HDML FAQ is found at this site http://www13.w3.org/TR/NOTE-Submission-HDML-FAQ
3G • A new radio communications technology that will create a "bit pipe" for providing mobile access to internet-based services.. • In the near future, mobility won't be an add-on: it will become a fundamental aspect of many services. We'll expect high-speed access to the internet, entertainment, information and electronic commerce. • 3G services will add an invaluable mobile dimension to services that are already becoming an integral part of modern business life:. • We will use 3G services enter our day -to-day lives in all sorts of new ways: for example, in shopping, banking, or playing interactive computer games over the Net.