Wireless
Application Protocol and 3-G Technology
Wireless Application Protocol (WAP)
Wireless Application Protocol (WAP) is
a defacto world standard that makes it possible to enhance
enterprise applications so that they can be accessed from virtually all
web-enabled phones. By 2005, the use of
Internet-enabled cell phones is expected to reach 96 million in
Before wireless applications can take
hold, what’s needed is a standard that corporate developers can use to provide
enterprise applications on the hundreds of different types of wireless devices
in use around the world. WAP addresses
this issue as it is an open specification standard for presentation and
delivery of wireless information and telephony services on mobile phones,
pagers, PDAs, and other wireless terminals.
At the heart of WAP applications is the microbrowser. A microbrowser is
needed because of the unique characteristics of wireless devices:
·
One finger
navigation
·
Smaller
screens
·
Limited
Ram/ROM
·
Usefulness of
location-based information
Wireless markup language (WML) provides
the foundation of a microbrowser specially designed
to capitalize on these unique factors.
It accomplishes this task by:
1.
Unlike a flat
document structure (like HTML in Internet applications) ,
WML structures it document in decks and cards.
2.
A card is
usually small enough to be displayed on even the smallest cell phone screens.
3.
The use of
decks provides the navigation model that calls for minimum interpage
navigation—the user is guided through a series of cards rather than having to
scroll up and down a page.
4.
WAP addresses
the limited memory and CPU of mobile phones and wireless devices by defining a
lightweight protocol stack that makes small claims on computational power and
memory resources.
5.
It addresses
bandwidth limitations by encoding transmissions into a compact form that
minimizes on-air traffic.
How does a WAP connection operate?
A
WAP connection consists of three elements:
1.
A WAP-enables
mobile phone
2.
A gateway that
provides the link between the mobile phone and the Internet
3.
The
application that is hosted on a conventional web server
A user select options from the
WAP-enabled devices using arrow keys, phone buttons, pen selectors, or some
other device to jump to specific pages.
The WAP stack of protocols covers the entire process of wireless content
delivery and resides on the gateway. The
actual request goes to the gateway, which translates requests from the WAP
protocol stack to the web protocol stack.
Content must be formatted to suitably
for the mobile phone’s small screen and low bandwidth/high latency
connection. Content is written in WML,
which includes a scripting language to provide client-side intelligence.
Tips for Content Conversion to WAP
At the heart of Wireless Applications is it’s content conversion form client-side applications to WAP’s card and deck structure. It is best to consider the value that would
be gained by accessing each application under consideration for the
protocol. Some points to remember are:
1.
Look for a
low-bandwidth application, keeping mind that you may be able to reduce the
amount of data handled by the application and still maintain its value
2.
In reducing
the amount of data, if current reporting presents 3-dimensional graphics that are
far too complex to be shown the screen of a cell phone, change its
presentation. Perhaps, only a few key
numerical values would fit or a different graphic could display the same
information.
3.
Try to save
money and time by leveraging existing code.
This is possible if applications are built with separate business logic
and presentation layers.
4.
Try to place
the entire screen within a single column, so that the application does not wrap
around the screen. There is no
horizontal scroll bar. Each object
should be placed on the left-hand edge of the interface and have the same
horizontal position of the other objects.
Long objects such as labels need editing.
5.
Eliminate all
unnecessary text and graphics to conserve screen space and bandwidth.
6.
If possible
combine host screens. For example, host
screens that show different currencies can be rewritten to a global variable
and the variables can be written to a second currency screen. All values may then be viewed
simultaneously.
WAP Organization Website:
White Papers on Wireless Application Protocol:
http://www.syntelinc.com/syntel/english/00000297/Syntel_wireless_naturalevolution.pdf
http://www.wapforum.org/what/WAP_white_pages.pdf
3-G
Cellular Technology
The UMTS (Universal Remote Telecommunications System) is the
so-called Third Generation (3G) Technology.
It is a broadband packet-based transmission of text, digitized voice,
video, and multimedia at data rates up to and possibly higher than 2 megabits
per second.
3G Technology will be available to
mobile computer and phone users throughout the world. Based on the GSM communication standard,
UMTS, endorsed by major standard bodies and manufacturers, it is currently
being implement as a standard for mobile users around the world.
Once UMTS is fully implemented, computer and phone users can be constantly attached to
the Internet as they travel and have the same set of capabilities no matter where they
travel to. Users will have access through a combination of terrestrial wireless and
satellite transmissions. (Until UMTS is fully implemented, users can
have multi-mode devices that switch to the currently available technology (such
as Gprs
and Edge ), and where UMTS is not yet available (Cf
spectrum page))
Today's cellular
telephone systems are mainly circuit-switched,
with connections always dependent on
circuit availability. Packet-switched
connections (WAP), using the Internet Protocol (IP), means that a virtual connection is always available
to any other end point in the network.
The higher bandwidth of UMTS also promises new services, such as video
conferencing. UMTS promises to realize the Virtual Home Environment in
which a roaming user can have the same services to which the user is accustomed
when at home or in the office, through a combination of transparent terrestrial
and satellite connections.
UMTS is a
network consisting of two main elements connected over a standard interface,
called Iu. These two
elements are:
·
UTRAN (UMTS Terrestrial Radio Access Network). This is composed of Node B which is equivalent to
the GSM BTS and the Radio Network Controller (RNC) which is equivalent to the
GSM BSC. A novelty with the UTRAN concept is the
existence of a new modulation scheme: the Frequency Division Duplex (FDD) and W-CDMA. This mode offers the
highest efficiency within a single system whatever the conditions—wide area,
urban, indoor coverage from outdoor, indoor, and so on. One carrier use 5 Mhz.
·
The Core Network. This
is the equivalent of the GSM NSS. There are two
options for the implementation of 3G and the evolution of the GSM Core
Network:
1.
Iu-PS (Packet Switched) interface instead of Gb on the packet domain.
2.
Iu-CS (Circuit
Switched) interface instead of A on the circuit domain.
3-G Technology also has a Transport Independent and
multimedia architecture: this R'00 (2000) architecture is
in line with the Next Generation Networks architecture and introduces separation of control and user planes.
It also integrates multimedia capabilities.
Differences between Conventional CDMA
and WCDMA:
Note the frequency band changes (Consolidation):
Note the limiting of
distortion because of rake processing available in W-CDMA
3-G Technology Website:
FOMA was the first in
http://www.3g-generation.com/foma.htm
Location of companies to view prototypes of Phones:
http://www.3g-generation.com/prototype.htm