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WAP and WML
DBI – Representation and
Management of Data on the Internet
Internet Connectivity Outlook
Millions
1,400
1,200
1,000
More handsets than PCs
connected to the Internet by
the end of 2003!
Projected
cellular
subscribers
Projected Web
handsets
800
600
Projected PCs
connected to
the Internet
400
(Dataquest 10/98)
200
0
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
'putting the Internet in everyone's pocket'
WAP
• WAP = Wireless Application Protocol
• A protocol and set of specifications to
connect wireless applications to the Web
Needs for WAP
• Wireless networks and phones
– have specific needs and requirements
– not addressed by existing Internet technologies
• WAP enables any data transport
– TCP/IP, UDP/IP, GUTS (IS-135/6), SMS, or USSD
• The WAP architecture
– several modular entities
– together form a fully compliant Internet entity
– all WML content is accessed via HTTP 1.1 requests
Advantages of WAP
• WAP utilizes standard Internet markup language
technology (XML)
• Optimizing the content and airlink protocols
• The WML UI components map well onto existing
mobile phone user interfaces
– no re-education of the end-users
– leveraging market penetration of mobile devices
• WAP utilizes plain Web HTTP 1.1 servers
– CGI, ASP, NSAPI, JAVA, Servlets, etc.
The Specification Includes
•
•
•
•
•
WAP Architecture
Wireless Application Environment
Protocol Layers
Interoperability
Security
WAP Architecture
Web Server
WAP Gateway
WML
WML Encoder
WMLScript
WSP/WTP
WMLScript
Compiler
HTTP
CGI
Scripts
etc.
WTAI
Protocol Adapters
Etc.
Content
WML Decks
with WML-Script
Client
Internet vs. WAP
Wireless Application Protocol
Internet
HTML
JavaScript
Other Services and
Applications
Wireless Application
Environment (WAE)
Session Layer (WSP)
HTTP
Transaction Layer (WTP)
Security Layer (WTLS)
TLS - SSL
Transport Layer (WDP)
TCP/IP
UDP/IP
Bearers:
SMS
USSD
CSD
IS136
CDMA
CDPD PDC-P
Etc..
Big Pipe - Small Pipe Syndrome
Internet
<HTML>
<HEAD>
<TITLE>NNN Interactive</TITLE>
<META HTTP-EQUIV="Refresh" CONTENT="1800,
URL=/index.html">
</HEAD>
<BODY BGCOLOR="#FFFFFF"
BACKGROUND="/images/9607/bgbar5.gif" LINK="#0A3990"
ALINK="#FF0000" VLINK="#FF0000" TEXT="000000"
ONLOAD="if(parent.frames.length!=0)top.location='http://
nnn.com';">
<A NAME="#top"></A>
<TABLE WIDTH=599 BORDER="0">
<TR ALIGN=LEFT>
<TD WIDTH=117 VALIGN=TOP ALIGN=LEFT>
HTTP/HTML
Wireless network
<WML>
WAP
<CARD>
<DO TYPE="ACCEPT">
<GO URL="/submit?Name=$N"/>
</DO>
Enter name:
<INPUT TYPE="TEXT" KEY="N"/>
</CARD>
</WML>
Content encoding
<HTML>
<HEAD>
<TITLE>
NNN
Interac
tive</T
ITLE>
<META
HTTPEQUIV="
Refresh
"
CONTENT
="1800,
URL=/in
dex.htm
l">
010011
010011
110110
010011
011011
011101
010010
011010
WAP Application
Environment Goals
• Network- neutral application environment
• For narrowband wireless devices
• With an Internet/WWW programming
model
• And a high degree of interoperability
Device-Side Problems
•
•
•
•
Device Independent
Network Independent
Different vendors – requires interfaces
Initial focus on phones
–
–
–
–
–
Slow reactions
Small memory
Limited CPU
Small screen
Limited input model
WML
Wireless Markup Language
WML
• Tag-based browsing language:
– Screen management (text, images)
– Data input (text, selection lists, etc.)
– Hyperlinks & navigation support
• Based on XML
WML (cont.)
• Card metaphor
– User interactions are split into cards
– Navigation occurs between cards
– Cards are put in to decks
• Explicit inter-card navigation model
– Hyperlinks
– User interface Event handling
– History
• State management and variables
– Reduce network traffic
– Results in better caching
All Decks Must Contain…
• Document prologue
– XML & document type declaration
• <WML> element
– Must contain one or more cards
<?xml version="1.0“?>
<!DOCTYPE WML PUBLIC "-//WAPFORUM//DTD WML 1.0//EN"
"http://www.wapforum.org/DTD/wml.xml">
<WML>
...
</WML>
Hello World Example
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card id="Card1" title="The dbi Course">
<p>
<!-- Hello World example -->
Hello World
</p>
</card>
</wml>
Basic Tags
• <wml> </wml> defines the
beginning and the ending of the
‘deck’, like <html> </html>
• <card> </card> defines the
beginning and the ending of a
card
The Result on Different Phones
Seeing the Result
• The content type of a WML text is
text/vnd.wap.wml
• You can send a created WML file with a
correct content type by
– Using
setContentType(“text/vnd.wap.wml”) in a
servlet
– By configuring Tomcat to return the right
content type for WML pages
Configuring Tomcat
• Due to a bug in Tomcat we will not use
/conf/web.xml
• We set the content type in the local
web.xml file
• For example, if the files are under a
directory webapps/dbi then we change the
file webapps/dbi/WEB-INF/web.xml
Setting the Content Type
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE web-app
PUBLIC "-//Sun Microsystems, Inc.//DTD Web
Application 2.2//EN“ "http://java.sun.com/j2ee/dtds/
web-app_2_2.dtd">
<web-app>
<mime-mapping>
<extension>
wml
</extension>
<mime-type>
text/vnd.wap.wml
</mime-type>
</mime-mapping>
</web-app>
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN“
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card title=“Text Formats">
<p> normal,
<strong>strong</strong>,
<em>emphasized</em>,
<b>bold</b>,
<i>italic</i>,
<u>underline</u>,
<big>big</big> and
<big><big>very big</big></big>,
<small>small</small>
<br/>
</p>
</card>
</wml>
Text Formats
deckit
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN“
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card title=“Table">
<p>
<table columns="2">
<tr><th><b>Name</b></th>
<th><b>Phone</b></th></tr>
<tr><td>Bart</td><td>123</td></tr>
<tr><td>Lisa</td><td>321</td></tr>
</table>
</p>
</card>
</wml>
Tables
Anchors
• The <anchor> tag defines what to do when
a user choose a link
– Comes with a task: go, pre, refresh
– For example,
<anchor>Login page
<go href=“login.wml"/> </anchor>
A Tag
• The <a> tag always performs a "go" task,
with no variables
• For example,
<a href=“login.wml">Login page</a>
Example
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN“
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card title=“Using A Tag">
<p>
<a href=“hello.wml">To Hello World</a>
</p></card>
</wml>
Handling User Input
• Select lists
– Choose from a list of options
• Input fields
– Enter a string of text or numbers
• KEY variables
– Set by SELECT and INPUT elements
– How user input is passed to other cards and the
application server
Select From Options
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN“
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card title=“Tutorials">
<p>
<select>
<option value="htm">HTML Tutorial</option>
<option value="xml">XML Tutorial</option>
<option value="wap">WAP Tutorial</option>
</select>
</p>
</card>
</wml>
Select From Options
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN“
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card title=“Tutorials">
<p>
<select multiple="true“ default=“htm; xml”>
<option value="htm">HTML Tutorial</option>
<option value="xml">XML Tutorial</option>
<option value="wap">WAP Tutorial</option>
</select>
</p>
</card>
</wml>
Input Fields
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN“
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card title="Input">
<p>
Name: <input name="Name" size="15"/><br/>
Age: <input name="Age" size="15"
format="*N"/><br/>
Sex: <input name="Sex" size="15"/> </p>
</card>
</wml>
Other INPUT Attributes
• DEFAULT=key_value
– Default KEY variable (displayed to user)
• FORMAT=format_specifier
– If omitted, free-form entry is allowed
• EMPTYOK="TRUE"
– Browser will accept null input, even with format
• TYPE=TEXT | PASSWORD
– Special entry mode handled by the browser
• MAXLENGTH=number
– Maximum number of allowed characters
FORMAT Control Characters
–
–
–
–
N
A, a
X, x
M, m
Numeric character
Alphabetic character
Numeric or alphabetic character
Any character
• Leading backslash specifies forced characters
• Forced characters included in KEY variable value
• Leading * specifies 0 or more characters
• Password:
FORMAT=“mmmm*m”
• Leading number specifies 0..N characters
• Zipcode: FORMAT=“NNNNN\-4N”
Tasks
• The <go> task represents the action of switching
to a new card
• The <prev> task represents the action of going
back to the previous card
• The <refresh> task refreshes some specified
card variables
– If any of the variables are shown on the screen, this task
also refreshes the screen
• The <noop> task says that nothing should be
done
The do Action
• The <do> tag can be used to activate a task
when the user chooses a word/phrase on the
screen
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card>
<p>
<do name="back" type="prev" label="Back">
<noop/> </do>
</p>
</card>
Overrides the Back link to
</wml>
noop
The DO Element
• Binds a task to a user action
– Action type:
– Label:
– Task:
– Destination:
– Post data:
ACCEPT, OPTIONS, HELP
PREV, DELETE, RESET
Text string or image (optional)
GO
PREV, REFRESH, NOOP
URL
if METHOD=POST
<DO TYPE="ACCEPT" LABEL="Next">
<GO URL="http://www.mysite.com/file.wml"/>
</DO>
Task Binding Rules
• User actions are scoped at three levels
• Deck
• Card
• Anchored links & select list options (ACCEPT)
– When tasks are bound to an action at different levels,
the action with narrower scope takes precedence
• Default task bindings
User Action
ACCEPT, PREV
Others
Task
PREV
NOOP
Variables
• Variables store data when a user switches
from card to card in a deck
• WML variables are case sensitive
• Setting a value to a variable:
<setvar name="i" value="500"/>
Set a value to i
Setting Variables From Input
<card id=“card1">
<select name=“i">
<option value=“500">The Number 500</option>
<option value=“Five Hundred">500 in Text</option>
</select>
</card>
Set a value to i
Get the value of i
<card id="card2">
<p>You selected: $(i)</p>
</card>
Detecting a Click
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card id=“Card1” title=“The DBI Course”>
<do type=“accept” label=“Next”>
<go href=“#Card2”/>
</do>
<p> Select Next to go to Card 2. </p>
</card>
<card id=“Card2” title=“The DBI Course”>
<p> I'm Card 2. </p>
</card>
</wml>
Events
• There are three types of events:
– onenterbackward – Occurs when the user
navigates into a card using a “prev” task
– onenterforward – Occurs when the user
navigates into a card using a “go” task
– ontimer – Occurs when the "timer" expires
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD
WML 1.1//EN“ "http://www.wapforum.org/
DTD/wml_1.1.xml">
<wml>
<card id="Intro" ontimer="#Main"
title=“DBI Course">
<timer value="150"/>
<p> Welcome to the dbi site!! We will
bring you to our main page after 15
seconds. </p> </card>
<card id="Main" title="Menu">
<p> This is our main page. Under
construction. </p>
</card>
</wml>
Timer
After 15
seconds
== DBI Course ==
Welcome
the dbi
===
Menuto
===
site!! is
This
We
ourwill
main
bring
page.
you
to our main
page after
Under
construction.
15 seconds.
___________________________
___________________________
Back
Back
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card id="main" title=“DBI Example">
<do type="accept" label="Next">
<go href="#wel"/> </do>
<p> Please enter your name:
<input type="text" name=“iname"/> </p>
</card>
<card id="wel" title="Welcome">
<do type="prev" label="Back"> <prev/> </do>
<p> Your name is $(iname).
Click Back to go to previous page.
</p> </card> </wml>
Input
Choosing the “Next”
Entering a name Choosing the “Options”
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card id="main" title=“DBI Example">
<do type="accept" label=“Send">
<go method=“POST"
href=“dbi/registerServlet">
<postfield name="firstname"
value="$(first)"/>
<postfield name=“course" value=“dbi"/>
</go> </do>
<p> Please enter your first name:
<input type="text" name="first"/> </p>
</card>
</wml>
Sending Data to the Server
Sending Data to the Server
<CARD>
<DO TYPE="ACCEPT">
<GO URL=“dbi/myServlet?id=$(sno)"/>
</DO>
<SELECT KEY=“sno” MULTIPLE="TRUE"
DEFAULT="1;3;5">
<OPTION VALUE="1">Bart</OPTION>
<OPTION VALUE="2">Lisa</OPTION>
<OPTION VALUE="3">Homer</OPTION>
<OPTION VALUE="4">Marge</OPTION>
<OPTION VALUE="5">Milhouse</OPTION>
<OPTION VALUE="6">Nelson</OPTION>
<OPTION VALUE="7">Smithers</OPTION>
<OPTION VALUE="8">Maggie</OPTION>
<OPTION VALUE="9">Burns</OPTION>
<OPTION ONCLICK="#card2">More...</OPTION>
</SELECT>
</CARD>
Collecting Data from More Than
One Card
<CARD>
<DO TYPE="ACCEPT" LABEL="Next">
<GO URL="#card2"/>
</DO>
First name:
<INPUT KEY="fname"/>
</CARD>
<CARD NAME="card2">
<DO TYPE="ACCEPT" LABEL="Done">
<GO URL=“dbi/myServlet" METHOD="POST"
POSTDATA="first=$fname&amp;last=$lname"/>
</DO>
Last name:
<INPUT KEY="lname"/>
</CARD>
Template Element
• The <template> tag defines a template for
all the cards in a deck
• The "code" in the <template> tag is added
to each card in the deck
• You can specify only one <template> tag
for each deck
• A template tag can only contain <do> and
<onevent> tags
The TEMPLATE Element
• Defines actions & events for all cards in a deck
<WML>
<TEMPLATE>
<DO TYPE="OPTIONS" LABEL="Main">
<GO URL="main_menu.wml"/>
</DO>
</TEMPLATE>
<CARD NAME="msg1">
<DO TYPE="ACCEPT" LABEL="Next">
<GO URL="#msg2"/>
</DO>
First story
</CARD>
<CARD NAME="msg2">
Second story
</CARD>
</WML>
First story
…
_____________
Next
Main
Second story
...
_____________
OK
Main
Another Template
<?xml version="1.0"?>
Example
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<template>
<do type="prev" label="Back">
<prev/>
</do>
</template>
<card id="card1" title="Card 1"> <p> <a
href="#card2">Go to Card 2</a> </p> </card>
<card id="card2" title="Card 2"> <p> <a
href="#card3">Go to Card 3</a> </p> </card>
<card id="card3" title="Card 3"> <p> Hello World!
</p> </card>
</wml>
Another Template
<?xml version="1.0"?>
Example
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<template>
<onevent type="onenterbackward">
<go href="#card1"/>
</onevent>
</template>
<card id="card1" title="Card 1"> <p> <a
href="#card2">Go to Card 2</a> </p> </card>
<card id="card2" title="Card 2"> <p> <a
href="#card3">Go to Card 3</a> </p> </card>
<card id="card3" title="Card 3"> <p> Hello World!
</p> </card>
</wml>
Displaying Images
• It is possible to insert images or local icons
within display text
– 1-bit BMP format
• Images are ignored by non-bitmapped devices
<CARD>
<DO TYPE="ACCEPT">
<GO URL="#c2"/>
</DO>
Continue <IMG LOCALSRC="righthand"
ALT="forward..."/>
</CARD>
<CARD NAME="c2">
<IMG SRC="../images/logo.bmp"
ALT="Unwired Planet"/>
<BR/>Welcome!
</CARD>
Image Attributes
• alt=“..”
– ‘Names’ the image
– If the image is not displayed by the browser the
label is displayed instead
• src="..
– Image source - where the image is located
• width="..
• height="..
– Sets the dimensions of the image.
– For example, the screen sizes of the devices is
Nokia 7110 (48 x 96 pixels)
WBMP
• Wap supports WBMP (Wireless Bitmap
Picture) 2 bit images
• It is possible to convert existing images
to wbmp
• The MIME type of the images is declered
with the following header:
Content-type: image/vnd.wap.wbmp
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card id="main" title="Where are you?">
<timer value="10"/>
<img src="snail2.wbmp" alt="A search snail"/>
</card>
<card id="look" title="I found you">
<img src="snail3.wbmp" alt="A looking snail"/>
</card>
</wml>
Adding Images
Special WML Characters
• Use character entities in display text
&quot;
&amp;
&apos;
&lt;
&gt;
&nbsp;
&shy;
"
&
'
<
>
Blank space
Soft hyphen (discretionary line break)
• Replace the “&” character in URL strings
URL=“myServlet?first=$fname&amp;last=$lname”
• Use “$$” to display a single “$” character
The <head> Tag
• The <head> tag contains information about
the document
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<head>
<access domain="www.cs.huji.ac.il"/>
<meta name="keyword" content="WAP"/>
</head>
....
....
</wml>
Doing more with WML
• Setting card styles to create forms
• Using variables to cache user data
• Using card intrinsic events to trigger
transparent tasks
• Using timers
• Securing WML decks
• Bookmarking decks
WMLScript
• Scripting language:
– Procedural logic, loops, conditionals, etc.
– Optimized for small-memory, small-cpu devices
• Derived from JavaScript™
• Integrated with WML
– Reduces overall network traffic
• Bytecode-based virtual machine
– Stack-oriented design
– ROM-able
WMLScript Standard Libraries
• Lang – VM constants, general-purpose math
functionality, etc.
•
•
•
•
•
String – string processing functions
URL – URL processing
Browser – WML browser interface
Dialog – simple user interface
Float – floating point functions
WMLScript Example Uses
• Reduce network round-trips and enhance
functionality
• Field validation
– Check for formatting, input ranges, etc.
• Device extensions
– Access device or vendor-specific API
• Conditional logic
– Download intelligence into the device
WMLScript Example
Functions
Variables
Programming
Constructs
function currencyConvertor(currency, exchRate) {
return currency*exchRate;
}
function myDay(sunShines) {
var myDay;
if (sunShines) {
myDay = “Good”;
} else {
myDay = “Not so good”;
};
return myDay;
}
WMLScript Example
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
"http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card id=“card1" title="Go to URL">
<do type="options" label="Go">
<go href="check.wmls#go_url(‘abc’)"/>
</do>
</card>
</wml>
WMLScript Example
extern function go_url(val)
{
if (val==“abc") {
WMLBrowser.go
("http://wap.google.com/start.wml")
}
}
Wireless Telephony Applications
• Tools for building telephony applications
• Designed primarily for:
– Network Operators / Carriers
– Equipment Vendors
• Network security and reliability a major
consideration
WTA (cont.)
• WTA Browser
– Extensions added to standard WML/WMLScript
browser
– Exposes additional API (WTAI)
• WTAI includes:
–
–
–
–
–
Call control
Network text messaging
Phone book interface
Indicator control
Event processing
WTA (cont.)
• Network model for client/server interaction
– Event signaling
– Client requests to server
• Security model: segregation
– Separate WTA browser
– Separate WTA port
• WTAI available in WML & WMLScript
WTA Example
Placing an outgoing call with WTAI:
WTAI Call
Input Element
<WML>
<CARD>
<DO TYPE=“ACCEPT”>
<GO URL=“wtai:cc/mc;$(N)”/>
</DO>
Enter phone number:
<INPUT TYPE=“TEXT” KEY=“N”/>
</CARD>
</WML>
WTA Example
Placing an outgoing call with WTAI:
WTAI Call
function checkNumber(N) {
if (Lang.isInt(N))
WTAI.makeCall(N);
else
Dialog.alert(“Bad phone number”);
}
References
• WAP Forum. http://www.wapforum.org/
• Unwired Planet, Inc. “Wireless Internet Today.” PDF File.
February 1999. http://www.phone.com/industry/wap.html
• Nokia Wireless Data Forum. “ Wireless Application
Protocol.” Web Page.
http://www.forum.nokia.com/developers/wap/wap.html
• Motorola “Wireless Application Development” PDF File
http://www.mot.com/MIMS/MSPG/spin/library_files/wad.
pdf
