introduction to mobile internet

Strathmore Mobile Boot CampNovember 2010

Mobile Website DevelopmentIntroduction to Mobile Internet

Facilitated by:Michael WakaheShujaa Solutions Ltd

Table of Contents

Copyright © Shujaa Solutions Ltd. 2010. All Rights Reserved.

The Need for Mobile Web

Mobile Web History



Limitations of mobile phones

Limited Processor Power and Memory

Limited Battery Life

Limited Input and Output Facilities

Low Bandwidth

Unpredictable Availability and Stability



TCP/IP protocol suite was not designed for a

wireless environment

Bandwidth resource is expensive

HTML pages are not suitable for use in mobile

devices with limited processor power and

screen.



Users consume mobile services differently.

They buy and pay for their mobiles and mobile

software differently.


Mobile devices available today can bebroken down in to a few broad classes:

1. Feature Phones

2. Smart Phones

3. PDAs

4. Voice-Only Phones



Feature Phones are the most common device type.

They usually come in candy bar, clamshell or slider form.

They have a 12-key layout and typically come with voice, messaging and data capabilities.



Figures: Feature Phones



Smart phones share the same features as a

feature phone with two primary differences:

its ability to run additional third-party applications

a slightly larger screen.



Smart phones typically use a more full featured operating system

Companies market them as them as advanced multimedia devices to consumers or as productivity devices to the business sector.



Figure: Smartphone - iPhone



PDAs evolved from the PDAs of the ‘90s Now often include voice, messaging, and data

capabilities. PDAs have much in common with smart

phone But differ in that much of their functionality is

oriented towards organizational tasks rather then voice communications.



Figure: Personal Digital Assistants



Voice-Only Phones are typically extremely low-cost phones aimed at developing markets

Are not relevant in the context of the Mobile Web.



Feature Phones lead the market by a large margin

However the borderline between the Feature Phones and Smart Phones is constantly shifting towards the Smart Phone category

The newest Feature Phones are often equal in functionality to yesterday’s Smart Phones.



Figure: Distribution of Mobile Handsets



The Web is a vast collection of servers linked by TCP/IP computer networks.

These web servers, implement the Hypertext Transfer Protocol (HTTP) to share documents and files.

Web servers provide access by Uniform Resource Identifiers (URIs) to text files, markup documents, and binary resources.



In an HTTP request, the client sends a web server the URI of the desired resource and a collection of request headers

One of the request headers contains a list of MIME types that advertise the content types supported on the client.



In an HTTP response, the web server sends the client the document itself (markup, text, or binary) and another set of headers

One of the response headers contains the MIME type describing the file type of the document transmitted to the client.


Mobile Web History


Mobile Web History


Wireless Application Protocol (WAP) Forum was

founded in 1997 by Ericsson, Motorola, Nokia, and

Phone.com.

WAP 1.1 was published in 1999

WAP 2.0 was published in 2001

Mobile Web History


In 2002, the WAP Forum consolidated into the Open

Mobile Alliance (OMA) and the specification work

from WAP continues within OMA

Mobile Web History


WAP is designed with two main goals

to minimize bandwidth requirement

to maximize the number of supported network

types (e.g., 9.6 Kbps in GSM).

Mobile Web History

Figure: The WAP protocol stack


Mobile Web History


WAP protocol stack is a lightweight protocol stack

that is designed to address the limitations of wireless

devices and the wireless network.

To access ordinary web servers, WAP-enabled mobile

devices can rely on a WAP gateway to provide

protocol conversion between WWW protocol stack

and WAP protocol stack.

Mobile Web History


WAP tries to utilize existing Internet protocols and

standards as much as possible

For example XML, HTML, HTTP & TLS

Mobile Web History


Each layer of the protocol stack is designed to be scalable and efficient.

For example, in Wireless Transaction Protocol (WTP), there is no explicit connection setup or teardown

Mobile Web History


To describe the capabilities of a mobile device, WAP

has defined a user agent profile (UAProf)

The capabilities of a mobile device are related to

software and hardware

This includes things like processor type, memory

capacity, display size, browser type and version,

network type, etc.

Mobile Web History


The aim of using UAProf is to allow all elements of the WAP infrastructure (i.e., content servers, application servers, gateways, etc.) to provide mobile devices with device-specific contents.

A user agent profile is basically an XML document containing information about hardware and software characteristics of a mobile device and network to which it will be connected.

Mobile Web History


The user agent profile of a mobile device is stored in its manufacturer's server, called the profile repository.

In order to provide mobile devices with device-specific contents, when a mobile device performs a request to a server, the URL of its user agent profile will be included in the header of the request message.

Mobile Web History


Example of UAProf: For Sony Ericsson K750i, found at: http://wap.sonyericsson.com/UAprof/K750iR101.xml

Open example XML

Mobile Web History


To reduce transmission time, WAP uses binary-coded

WML (wireless markup language) pages.

Also WAP specifies a caching model and user agent

profile (UAProf) for efficient delivery of device-

specific content.

Mobile Web History


HTML pages are not suitable for use in mobile

devices with limited processor power and screen.

Wireless Markup Language (WML) is designed to

describe data and the format that data should be

presented on mobile devices

Mobile Web History


WML is a tagged language.

WML adopts a deck and card metaphor.

Each WML document is made up of multiple cards,

and cards are grouped into a deck.

WML pages can be encoded in a binary format

before transmission.

Mobile Web History


<wml>

<card id=“Card1" title="First Card"><p>

Hello World!</p>

</card>

<card id="Card2" title="Second Card"><p>

WAP is fun!</p >

</card>

</wml>

Mobile Web History


Figure: A WML deck with two cards.

Mobile Web History


WMLScript is a scripting language which

complements WML.

Similar to JavaScript for HTML

WMLScript bytecode interpreter is compact in size,

which allows efficient execution of scripts will less

memory and processor requirements

Mobile Web History

Three elements in a WAP architecture: Client: the WML browser in a wireless device.

It issues WAP requests to a server.

Server: the entity which provides services and where resources are located. This can be an ordinary Internet-based server or a WAP-capable server.


Mobile Web History

Gateway: provides protocol conversion between the WWW protocol stack and the WAP protocol stack, by using content encoders and decoders

Thus a gateway acts as a proxy server


Mobile Web History

Figure: WAP infrastructure.


Mobile Web History

When protocol conversion is performed at the gateway, it can minimize wireless communication overhead at the client side.

The gateway can also cache frequently requested contents so as to reduce the request - response time.


Mobile Web History

The architecture discussed so far is the common pull architecture based on the client - server paradigm

WAP system architecture also specifies a push architecture to enhance the WAP services

Here the server sends messages to the client without explicit request from the client.


Mobile Web History

Push architecture is very useful in delivering messages like instant news, email indication, advertising etc

In the push architecture, the server and the gateway are called the push initiator (PI) and the push proxy gateway (PPG), respectively.


Mobile Web History

Figure: WAP push architecture


Mobile Web History


WAP is designed to meet the following requirements

Interoperability

Scalability

Efficiency

Reliability

Security

Mobile Web History

Mobile Web uses the plumbing of Desktop Web and adds new MIME types, markup languages, document formats, and best practices

Web content provided is optimized for the small screens, resource constraints, and usability challenges of web browsers on mobile devices.


Mobile Web History

The Mobile Web introduces new components into the web ecosystem, including: Markup languages and styles optimized for

mobile devices MIME types that differentiate mobile markup

from desktop HTML Browser clients with a wide variety of capabilities Network proxies that further adapt your content

to cater for those clientsCopyright © Shujaa Solutions Ltd. 2010. All

Rights Reserved.

Mobile Web History

Rich Web 2.0 features such as JavaScript frameworks and Asynchronous JavaScript and XML (AJAX) must be used judiciously, or you risk draining battery power.

Operators frequently control and block traffic to Mobile Web sites.


Mobile Web History

Transcoding proxies often attempt to reformat mobile markup en route to a mobile browser.

Defensive programming is essential to reduce exposure to transcoders and mobile network problems.


Mobile Web History

Mobile users are keenly goal-directed and location-aware.

Roaming in and out of coverage areas, mobile users count network access problems among the top factors affecting the Mobile Web browsing experience.


Mobile Web History

The mobile browser is totally new & has unique benefits, quirks, and workarounds.

Partial and flawed implementations of web standards are commonplace.


Mobile Web History

Improperly formatted web pages can have drastic effects on mobile devices, including crashing the browser or resetting the device.

Advanced web features such as JavaScript and AJAX are highly desirable but drain battery life.


Mobile Web History


introduction to mobile internet

Technology

mobile web voice

mobile web pdas

mobile web users

mobile web feature phones

mobile web smart phones

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