Transcript Document

WAP/ WML
Author :Hsien-Pang Tsai
Outlines
Introduction
 WAP Architecture
 WML
 Conclusion
 Reference

Outlines
Introduction
 WAP Architecture
 WML
 Conclusion
 Reference

Wireless Application Protocol (WAP)

An specification that empowers mobile
users with wireless devices to easily
access and interact with information and
services instantly.
Purpose
Bring Internet content and to digital cellular
phones.
 Create a specification that will work across
differing wireless network technologies.
 Embrace and extend existing standards
and technology wherever appropriate.

WWW Model vs. WAP Model
WAP Push

Real-time applications that send
notifications to their users
 Poll
application servers for new information or
status.
 Push functionality provides control over the
lifetime of pushed messages, store & forward
capabilities at the Push Proxy and control
over bearer choice for delivery.
Feature-Enhancing Proxies
Outlines
Introduction
 WAP Architecture
 WML
 Conclusion
 Reference

WAP Stack Architecture
Protocol Stack

Legacy Protocol Layers
 Optimized
for low bandwidth bearer networks
with relatively long latency.
 Protocol Layers for Networks Supporting IP
 Motivated by the emergence of high-speed
wireless networks (e.g. 2.5G and 3G) .
 Provide IP support directly to the wireless
devices.
Legacy Protocol Layers

WAE：Wireless Application Environment
 WAP
2.0 provides the foundation for such a
micro-browser in its markup languages,
namely the XHTML Mobile Profile markup
language (XHTMLMP).
 Enhances the presentation of content by
supporting style sheets.

WSP：Wireless Session Protocol, provides the
upper-level application layer of WAP with a
consistent interface for two session services.
 connection-mode
 connectionless service
Secure datagram
 Non-secure datagram

 WTP：Wireless Transaction Protocol, defined
as a light weight transaction oriented protocol for
mobile stations and operates efficiently over
wireless datagram networks.

WTLS：Wireless Transport Layer Security,
designed to provide privacy, data integrity and
authentication between two communicating
applications.
 Provides an interface for managing secure
connections.
 Datagram support, optimized handshake and
dynamic key refreshing.

WDP：Wireless Datagram Protocol, a general
datagram service, offering a consistent service
to the upper layer protocols and communicating
transparently over one of the available
underlying bearer services.
Protocol Layers for Networks
Supporting IP

WP-HTTP：Wireless Profiled HTTP, is a
profile of HTTP for the wireless environment and
is fully interoperable with HTTP/1.1.
 Message body compression of responses.
 The establishment of secure tunnels.

TLS：Transport Layer Security, permit
interoperability for secure transactions.

WP-TCP：Wireless Profiled TCP, provides
connection-oriented services, which is optimized
for wireless environments and is fully
interoperable with standard TCP.
Dual WAP Stack


WAP 2.0 provides
support for both stacks, it
should be noted these
stacks operate
independently.
would not be mixing and
matching of protocols in
accomplishing an end-toend transaction.
WAP Network
Outlines
Introduction
 WAP Architecture
 WML
 Conclusion
 Reference

Wireless Markup Language (WML)


WML2 is a language which extends the XHTML
Basic and CSS Mobile Profile.
Optimised for specifying presentation and user
interaction on limited capability devices such as
mobile phones and other wireless mobile
terminals.
GOAL

There are five goals for WML2:
 Backward
compatibility.
 Convergence with existing and evolving
Internet standards.
 Optimisation of access from small, limited
devices.
 Allowance for the creation of distinct user
interfaces.
 Internationalisation of the architecture.
WML2 Document Structure
Ex：
Card & Deck
User Agent Behaviour
Variables
 Navigation History
 Navigation Reference Processing Model
 Form Processing Reference Model
 WML2 Event Model

Variables


A WML variable is a name-value pair, where the
value is any string in the document character set.
WML variables can be used in the place of
strings and are substituted at run-time with their
current value.
Navigation History


The user agent history is modelled as a stack of
entries that represent the resources in the
navigational path the user traversed to arrive at
the current location.
Three operations may be performed on the
history stack:
 Reset
 Push
 Pop
Navigation Reference Processing
Model

A task is a navigational directive executed
by the user agent in response to an event
such as the activation of a wml:do element
or the expiration of a timer.
 The
go task
 The prev task
 The noop task
 The refresh task
Event Model


Intrinsic event: an event generated by the user
agent
Extrinsic event: an event sent to the user agent
by some external agent
Event Binding

Card-level: the event binding may appear
inside a body or wml:card element and specify
event-processing behavior for that particular
card or body.
 Document-level: the event binding may
appear inside the html element and specify
event-processing behavior for each body/card in
the document.
 A document-level
event binding is equivalent to
specifying the event binding in each body/card.
Ex：
Conclusion
Introduction
 WAP Architecture
 WML

Reference


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WAP Architecture Spec. [WAP-210-WAPArch-20010712]
 http://www.wapforum.org
WAP 2.0 White Paper [2002-Jan]
 http://www.wapforum.org
Wireless Markup Language v2.0 [WAP-238-WML20010626-p]
 http://www.wapforum.org /Jan-26-2001
WML輕鬆打 .wap手機網站
 http://www.class2u.idv.tw/html/wml/index.htm

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