Internet _ Wireless

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					Today, after more than a century of electric technology, we have
extended our central nervous system itself in a global embrace,
abolishing both space and time as far as our planet is concerned.

The Internet is a complex space with a rich set of useful features and
functions. Knowing how to get the most out of the Internet can help
you as much as knowing how to read, maybe more.

Internet History
In 1957, the Soviet Union launched the first satellite, Sputnik I,
triggering US President Dwight Eisenhower to create the ARPA agency
to regain the technological lead in the arms race. ARPA appointed
J.C.R. Licklider to head the new IPTO organization with a mandate to
further the research of the SAGE program and help protect the US
against a space-based nuclear attack. Licklider evangelized within the
IPTO about the potential benefits of a country-wide communications
network, influencing his successors to hire Lawrence Roberts to
implement his vision.

Roberts led development of the network, based on the new idea of
packet switching discovered by Paul Baran at RAND, and a few years
later by Donald Davies at the UK National Physical Laboratory. A
special computer called an Interface Message Processor was
developed to realize the design, and the ARPANET went live in early
October, 1969. The first communications were between Leonard
Kleinrock's research center at the University of California at Los
Angeles, and Douglas Engelbart's center at the Stanford Research
Institute.

The first networking protocol used on the ARPANET was the Network
Control Program. In 1983, it was replaced with the TCP/IP protocol
developed by Robert Kahn, Vinton Cerf, and others, which quickly
became the most widely used network protocol in the world.

In 1990, the ARPANET was retired and transferred to the NSFNET. The
NSFNET was soon connected to the CSNET, which linked Universities
around North America, and then to the EUnet, which connected
research facilities in Europe. Thanks in part to the NSF's enlightened
management, and fueled by the popularity of the web, the use of the
Web Browser Application
Internet exploded after 1990, causing the US Government to transfer
management to independent organizations starting in 1995.

There are three leading web browser applications, and several other options.


Dozens of browsers have been developed over the years, many of which are
described in the section on browser history. Today, most people use one of the
mainstream browsers: Explorer or Mozilla. Some people run more than one browser,
but you can conveniently keep all of your bookmarks only in one, and links only get
marked as visited in the browser you use, so you probably want to standardize on
one browser for most of your surfing.


A high-level trade-off matrix between the top three browsers is shown below. You
can also ask your friends for their experiences, and download and try several
browsers.


               Trade                Pro                     Con

            Internet    Faster.                 Integrated with OS, more
            Explorer                            vulnerable to viruses.
                        More web application
                        features.               More complex, deeper
                                                menus.

            Mozilla     Open source.            Not quite as fast for some
            FireFox *                           functions on Windows.
                        Good bookmark
                        functionality.          Less widely used on
                                                Windows.
                        Multi-platform.


                        Available email
                        (Thunderbird),
                        newsgroups, and IRC
                        clients


This Living Internet site recommends Mozilla Firefox because it is well coded,
multi-platform, open source, compliant with web standards, and has the best
bookmarking and tabbed viewing functionality.
Mozilla also has developed a suite of basic Internet applications, including an email
program and newsgroup reader called Thunderbird, and an associated ChatZilla IRC
client. These open source applications perform well on all platforms, and get better
with each release.


Other browsers. There are several other web browsers which compete on various
feature sets and have different strengths:


   Arachne -- A graphical full screen web browser for DOS computers.


   Lynx -- A venerable web browser for character mode terminals without graphics
   originally developed at the University of Kansas Academic Computer Services
   Distributed Computing Group.


   NeoPlanet -- Integrates several Internet applications together, including a
   browser, email, and chat.


   NetCaptor -- A user-friendly browser built on top of Internet Explorer.


   Opera -- Small, fast, customizable application.


Usenet Newsgroup Descriptions

Various kinds of newsgroup descriptions are maintained in different places around
the Internet. There are three main places you can look for newsgroup descriptions:


Charters. Some newsgroups regularly post a description to the group that describes
its intention. These descriptions are posted by the people involved with the
newsgroup creation and/or administration. If the group has such a description, it
almost always includes the word "charter", so you can quickly find it by searching
the newsgroup for that word.


RFD. You can check to see if the group has an original "Request For Discussion"
description in the archive of all news, announce, newgroups postings from late 1989
to March 1996.


Descriptions. Many newsgroups have short descriptions at newsgroup review sites,
although these are of varying quality.
Short Message Service (SMS)

Short Message Service (SMS), a service that delivers text messages of up to 160
alphanumeric characters, is one option for delivering wireless advertisements. When
marketers send SMS messages, the length, creativity and interactivity of the message
are limited because the message cannot contain graphics. However, text messages
take far less time to load than do rich multimedia and graphics-packed messages.
SMS can also be used to send mobile alerts, which provide customers with valuable
news and product updates.


SMS Benefit on business

Alternatively, companies can send promotions to customers by distributing e-coupons
to user’s wireless devices. For example, wireless promotions delivered to automobile
drivers and passengers can alert them to nearby shopping malls, gas stations and
restaurants that are offering special deals. However, some users might find this kind
of advertising intrusive. A wireless promotional strategy can enable opt-in users to
indicate the type and amount of promotional information they wish to receive, as well
as allowing them to select the time of day that the coupons will be sent.


Wireless Payment

Secure electronic funds transfer and positive user transaction experiences are crucial
to the success of e-commerce and m-commerce. Businesses that offer domestic and
international products and services must ensure that m-payments )payments made via
wireless devices) will be received securely and that the transactions are valid.


The variety of wireless devices, the lack of m-payment interoperability and the
immaturity of the m-payment industry have led to inconsistent user experiences.
Interoperability, the ability for transactions to be performed using and software or
device, is a major hurdle for the m-payment market. Organizations such as Global
Mobile Commerce Interoperability Group (GMCIG) and Mobile Electronic
Transactions (MeT) Group support standards that enhance interoperability.


Privacy and the Wireless Internet

The Internet presents many new consumer privacy issues. When people communicate
through wireless devices, privacy is further threatened; transmissions can be
intercepted, and users can be located with a high degree of accuracy. Wireless
location-tracking will offer access to information about users¡¦ activities, including
where they go, when they go and the length of their stay. Over time, a compilation of
this data could contribute to a substantial profile of a user’s habits.


Currently. the accepted protocol for collecting a use this information is called an
opt-in policy - i.e. the user agrees to the collection of his or her personal information
in exchange for receiving targeted content. In some cases, a business installs a double
opt-in policy. Double opt-in policies require the user to request information and then
to confirm that request by replying to a follow-up e-mail. This practice provides
greater protection of privacy theoretically. An opt-out policy enables an ?Id arketing
information to consumers until individual users request to mailing list.


When an opt-in policy is used. consumers should request and expect the information
that they receive from advertisers. Companies that wish to collect personal
information must inform consumers as to how their information will be managed. The
complicated legalese of privacy policies could be difficult to display effectively on
small interfaces. making the wireless Internet more susceptible to privacy violations.
For example, if a company has partners or affiliates, location information might be
shared with and used by these companies. As a result, consumers could find
themselves bombarded with unsolicited email-while they are in their cars, at the
movie theater or enjoying an evening out. In addition, although the Federal
Communications Commission (FCC) has guidelines outlining a telecommunications
carriers responsibilities for protecting a users privacy, marketers and vendors are not
subject to the same guidelines. 12 Third-party vendors. in most cases. will have their
own privacy policies.


To date. there is no legislation that monitors the use and misuse of
location-identification technology. Industry leaders and government agencies fear that
such legislation could slow the development of wireless technology. Even if the
government perceives a need for regulation. there are many ways to approach privacy
legislation: one comprehensive¡¦ privacy law could target some issues. but miss others.
Personal information collected from wireless users, for example, can be of a different
nature than that collected from wired users.


International Wireless Communications

Wireless communications and related technologies are driving forces behind the
global economy. The United States does not dominate the worlds wireless
communications market; in fact, researchers estimate that the United States is up to
two years behind the forefront of wireless technology. Although more Americans
subscribe to cell-phone service than do citizens of any other country, the U.S. market
penetration (i.e.. the percentage of the population using the service) is lower than that
in 10 of the top 20 wireless markets. Competing wireless standards and the
availability of inexpensive wireline phone service have slowed the adoption of
wireless technology in the United States. As a result, the percentage of Europeans
who own cell phones is nearly twice that of Arnericans.


The popularity of certain wireless applications differs greatly from country to country.
For example, European consumers have embraced text-messaging services, whereas
Americans often limit cell-phone use to voice applications. In addition, the United
States has an extensive wireline telecommunications infrastructure that delivers
relatively inexpensive telephone service and Internet access. Many other parts of the
world do not have the same level of infrastructure, making telephone and Internet
service costly and difficult to access . Some developing regions are turning to wireless
infrastructure solutions by implementing wireless local access, as well as wireline
networks. 15 Wireless local access refers to the establishment of wireless networks
that serve as primary telephone and Internet connections.


Next to voice service, messaging is the most popular cell-phone application in the
global market. Messaging refers to the transmission of brief text messages to the
display of another cell phone. According to the Global System for Mobile
Communications (GSM) Association. an organization that supports the extensive
GSM cell-phone system, 15 billion Short Message Service (SMS) text messages were
sent over GSM wireless networks during December 2000. SMS is used to send short,
e-mail-like messages, as well as to alert subscribers to new c-mails, faxes or voice
messages. Carriers worldwide are launching SMS Web portals that offer rn-commerce
applications, corporate services, sports, financial news and weather-based information
services. In addition, individuals are creating innovative uses for SMS services;
televised award ceremonies poll audiences via SMS, and some religions use SMS to
send reminders regarding prayer time.


Wireless-Communications Technologies

The proliferation ofwireless consumer devices. such as personal digital assistants
(PDAs). digital cell phones and two-way pagers is increasing the demand for
rn-business and rn-commerce. Wireless devices enabled with Internet access allow
users to manage their personal and professional lives while away from their desktop
computers. By using PDAs, such as the Palm handheld computer and the Pocket PC,
as well as digital cell phones and laptop computers, users can buy airline tickets and
groceries, trade stocks and check their e-mail from remote locations.


Wireless communications technologies are categorized and identified h generation.
These include first generation (1G). second generation (2G), two-and-a half
generation (2.5G). third generation (3G) and even fourth generation (4G). The analog
cell phone is an example of a first-generation technology. As wireless
communications evolved from analog to digital transmission, first-generation
technologies gave way to second-generation technologies. Second-generation
technology, which offers transmission speeds of up to 9.6Kbps, is the current standard
for the United States. Today. service providers are developing the next
generation-third generation (3G) of transmission technologies, which promises speeds
far greater than those of standard dial-up connections.


3G

The 2.5-generation technologies represent an intermediate step between
second-generation and third-generation technologies. These technologies rely on
networks that use packet switching technologies (information is divided into packets
when it is sent and then reassembled at the receiving end). Many countries, with the
exception of Japan and parts of Europe, do not have the spectrum available or the
networks to support 3G technologies. Even in Japan and Europe, 3G technologies are
not expected to be widely available until 2003 or even 2005. The services are not
expected to be released in the United States until 2006.
3G technology enables increased data speeds, larger network capacity and
transmission support of multiple data types, video, multimedia, voice and data.
Japan¡¦s NTT DoCoMo leads the world in the development of third-generation
technologies with the anticipated release of Wideband Code Division Multiple Access
(WCDMA).


NTT DoCoMo is also the developer of i-mode, the most popular wireless Internet
service, which boasts over 25 million subscribers. Using a compact version of HTML
called dHTML, i-mode offers voice services combined with text messaging, animated
graphics and Web browsing.
WAP and WML

In the wireless world, there are many programming platforms and technologies. The
Wireless Application Protocol (WAP) and Wireless Markup Language (WML) are the
most commonly used technologies for wireless communications in the United States;
they also are popular in parts of Europe and Asia. In the following sections, we
demonstrate how to build wireless applications that use WAP/WML.


Bluetooth Wireless Technology

Bluetooth wireless technology enables kwower. short-range wircless communications
between computers, PDAs, cell phones and other devices. This technology has the
potential to reduce and even eliminate the need for wires in offices, homes, cars and
elsewhere.


Bluetooth wireless technology communicates by using radio frequencies to create a
personal area network (PAN) of connected devices, a so called a piconet. Bluetooth
technology supports point-to-point communication, through which a
Bluetooth-enabled device, such as a wireless phone, sends a signal to one other device,
as well as point-to-multipoint communications, that connects one device to up to
seven others. One Bluetooth device can recognize and connect to any other Bluetooth
-enabled device within a 30 feet radius. For example, imagine that an employee uses a
FDA to schedule a meeting with another user in the network. When both users return
to their desktop computers, the information stored on their PDAs can be transferred to
the users¡¦ desktop computer calendars by using Bluetooth wireless technology
instead of user commands. This eliminates the need for users to perform a manual
synchronization process later to update devices.


More than 2.200 companies are members of the Bluetooth Special Interest Group
(SIG) (www.bluetooth.com). The SIG pools the patents of member companies and
provides a free intellectual property license to member companies as long as the
members submit products to qualification testing before sending their Bluetooth
products to market.


Wi-Fi

Wi-Fi is a brand originally licensed by the Wi-Fi Alliance to describe the underlying
technology of wireless local area networks (WLAN) based on the IEEE 802.11
specifications. It was developed to be used for mobile computing devices, such as
laptops, in LANs, but is now increasingly used for more services, including Internet
and VoIP phone access, gaming, and basic connectivity of consumer electronics such
as televisions and DVD players, or digital cameras. More standards are in
development that will allow Wi-Fi to be used by cars in highways in support of an
Intelligent Transportation System to increase safety, gather statistics, and enable
mobile commerce (see IEEE 802.11p). Wi-Fi and the Wi-Fi CERTIFIED logo are
registered trademarks of the Wi-Fi Alliance - the trade organization that tests and
certifies equipment compliance with the 802.11x standards.


A typical Wi-Fi setup contains one or more Access Points (APs) and one or more
clients. An AP broadcasts its SSID (Service Set Identifier, "Network name") via
packets that are called beacons, which are usually broadcast every 100 ms. The
beacons are transmitted at 1 Mbit/s, and are of relatively short duration and therefore
do not have a significant effect on performance. Since 1 Mbit/s is the lowest rate of
Wi-Fi it assures that the client who receives the beacon can communicate at at least 1
Mbit/s. Based on the settings (e.g. the SSID), the client may decide whether to
connect to an AP. If two APs of the same SSID are in range of the client, the client
firmware might use signal strength to decide which of the two APs to make a
connection to. The Wi-Fi standard leaves connection criteria and roaming totally open
to the client. This is a strength of Wi-Fi, but also means that one wireless adapter may
perform substantially better than another. Since Wi-Fi transmits in the air, it has the
same properties as a non-switched wired Ethernet network, and therefore collisions
can occur. Unlike a wired Ethernet, and like most packet radios, Wi-Fi cannot do
collision detection, and instead uses a packet exchange (RTS/CTS used for Collision
Avoidance or CA) to try to avoid collisions.


Except for 802.11a, which operates at 5 GHz, Wi-Fi uses the spectrum near 2.4 GHz,
which is standardized and unlicensed by international agreement, although the exact
frequency allocations vary slightly in different parts of the world, as does maximum
permitted power. However, channel numbers are standardized by frequency
throughout the world, so authorized frequencies can be identified by channel
numbers.


Wi-Fi Channel

The frequencies for 802.11 b/g span 2.400 GHz to 2.487 GHz. Each channel is 22
MHz wide and there is a 5 MHz step to the next higher channel.
The maximum number of available channels for wi-fi enabled devices are: – 13 for
Europe - 11 for North America - 14 for Japan


Advantages of Wi-Fi

i). Allows LANs to be deployed without cabling, typically reducing the costs of
network deployment and expansion. Spaces where cables cannot be run, such as
outdoor areas and historical buildings, can host wireless LANs.


ii). Wi-Fi silicon pricing continues to come down, making Wi-Fi a very economical
networking option and driving inclusion of Wi-Fi in an ever-widening array of
devices.


iii). Wi-Fi products are widely available in the market. Different brands of access
points and client network interfaces are interoperable at a basic level of service.
Products designated as Wi-Fi CERTIFIED by the Wi-Fi Alliance are interoperable and
include WPA2 security.


iv). Wi-Fi is a global set of standards. Unlike cellular carriers, the same Wi-Fi client
works in different countries around the world.


v). Widely available in more than 250,000 public hot spots and millions of homes and
corporate and university campuses worldwide.


vi). As of 2006, WPA and WPA2 encryption are not easily crackable if strong
passwords are used


vii). New protocols for Quality of Service (WMM) and power saving mechanisms
(WMM Power Save) make Wi-Fi even more suitable for latency-sensitive
applications (such as voice and video) and small form-factor devices.


Disadvantages of Wi-Fi

i). Wi-Fi can be interrupted by other devices, notably 2.4 GHz cordless phones and
microwave ovens.


ii). Spectrum assignments and operational limitations are not consistent worldwide;
most of Europe allows for an additional 2 channels beyond those permitted in the US
(1-13 vs 1-11); Japan has one more on top of that (1-14) - and some countries, like
Spain, prohibit use of the lower-numbered channels. Furthermore some countries,
such as Italy, used to require a 'general authorization' for any Wi-Fi used outside an
operator's own premises, or require something akin to an operator registration.


iii). Power consumption is fairly high compared to some other standards, making
battery life and heat a concern.


iv). The most common wireless encryption standard, Wired Equivalent Privacy or
WEP, has been shown to be breakable even when correctly configured.


v). Many 2.4 GHz 802.11b and 802.11g Access points default to the same channel,
contributing to congestion on certain channels.


Conclusion

Wireless technology has developed into one of today’s hottest topics because of its
ability to bring the power of communications and the internet into the hands of users
worldwide. Wireless communications affects many aspects of society, including
business management and operations, employee productivity, consumer purchasing
behavior, marketing strategies and personal communications. As the popularity of
wireless services grows, manufacturers are enabling wireless devices with an
increasing array of features and capabilities.


Wireless communications also can be used to improve customer relationship
management (CRM). CRM focuses on providing and maintaining quality service for
customers by effectively communicating and delivering products, services,
information and solutions. By using wireless devices, customers can receive timely
and relevant information on demand, and companies can interact more efficiently with
their sales and field forces.


For employers and employees, wireless access provides the ability to communicate,
access corporate databases, manage administrative tasks (such as answer e-mail and
schedule meetings) and enhance customer relations.


In addition, wireless communications enables the streamlining of product shipment
and tracking. Furthermore, both employees and consumers can manage
responsibilities and complete tasks during idle time-waiting for a bus, or standing in
line at a bank.

				
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