Wireless

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Sara Saad Al-Qahtani 427201054 Ebtissam
Al-Motairy 427202249 Section 2518 Time
(8-9) English 104
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Wireless
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Wireless What is Wireless?

• The purpose of this guide is to identify the
  concepts of wireless technology and how to use it
  effectively.
• The word wireless is one of those industry
  buzzwords that has many different meanings, and
  each is different depending on the circumstances.
  
• In general, you can safely divide the world of
  wireless into two types of technology.

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Wireless What is Wireless?

• Types of wireless technologies
• Cellular
• Cellular wireless technology encompasses all that
  has to do with long-range wireless communication
  cellular phones, pagers, and Short Message
  Service (SMS) devices, for example.
• Wifi
• Wi-fi (short for Wireless Fidelity) technology is
  all that has to do with transferring data between
  devices over a short range, and encompasses uses
  like wireless local networks, Bluetooth
  networking for PDAs, and wireless keyboards, for
  instance.

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Wireless What is Wireless?

• Understanding Cellular
• Understanding Wi-fi

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What is Wireless? Understanding Cellular
Cellular Network                                
                                        

• The biggest difference between cellular and wi-fi
  wireless technology is the range and the
  frequency. Cellular devices broadcast their
  signals on lower frequencies than wi-fi cellular
  signals are usually measured in Megahertz (Mhz).
• For example, in the US, most cellular phones
  operate in the 800 or 1900 Mhz frequency bands.
• Cellular was designed from the beginning to offer
  service over a large area, like an entire city.
  Cellular wireless is called cellular because a
  complete access area is made up of a network of
  cells. Each transmitter sends and receives
  signals only within a certain range, known as a
  cell. As the phone moves between cell ranges, the
  phone seamlessly switches the signal from one
  cell's channel to the other.

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What is Wireless? Understanding Cellular

• The generation gap
• Cellular phones are nothing new, of course. Over
  the last thirty years, the technology has gone
  through enough changes to identify three distinct
  "generations". Currently, cellular devices are
  starting to make use of third generation (3G)
  technology.

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What is Wireless? Understanding Cellular

• Analog
• Analog means that the signal is sent and received
  is continuous. It is not broken down into tiny
  chunks (called samples) like a digital signal.
• The standard for analog cellular telephone
  service in the US since 1983 has been AMPS
  (Advanced Mobile Phone Service) for many years
  now. This is now known as the first generation
  technology. Analog cellular service is still in
  use (in fact, 80 of the US still has analog
  coverage, including rural areas where digital
  service is not yet available), but it is losing
  ground to digital cellular services for several
  reasons
• Analog cellular signals handle fewer calls at
  once than their digital counterparts
• Digital cellular can enhance the quality of the
  signal, eliminating some types of noise in areas
  where the signal is weaker.
• Digital cellular enables more services than just
  voice-e-mail, text messaging, and more can be
  sent over a digital signal.
• Analog signals are less secure than digital
  signals, and it is easier to eavesdrop on analog
  calls.

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What is Wireless? Understanding Cellular

• Analog Signal

Digital Signal
Analog signals have a continous form.   Digital
representations of an analog signal are values
sampled at discreet intervals.
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What is Wireless? Understanding Cellular

• Digital
• Digital cellular service uses the same
  frequencies as analog cellular, but the signal is
  broken into tiny chunks (sampled), broadcast as
  binary numbers, and then re-assembled when
  received by the cellular device. The fact that
  the signal is transmitted in a binary format
  means that additional information can be added to
  the signal, permitting better use of bandwidth
  (i.e., more calls per frequency), better
  security, and enhanced services (like call
  display, for example).
• CDMA
• Code Division Multiple Access is the predominant
  digital cellular technology in North America.
  Code division means that each call is assigned a
  unique code, and is then transmitted across
  multiple frequencies, depending on what is
  available. Because each digital call has a unique
  code, many calls can occupy the same frequencies
  at the same time, and still be routed accurately
  when received by the cell sites.

• Bandwidth is the amount of data that
• can be transferred at once over a network.
• It is usually measured in megabits-per-second
  (Mbps).

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What is Wireless? Understanding Cellular

• GSM
• The Global Standard for Mobile communications
  (GSM) is the predominant digital cellular
  technology in Europe and Asia. GSM originally
  used a combination of two digital formats TDMA
  and FDMA. Frequency Division Multiple Access
  divides the call up into chunks by frequency,
  while Time Division Multiple Access splits each
  call up into chunks and assigns each a time slot
  within a given frequency. GSM technology splits
  the calls into their own time slots, but also
  spreads the chunks across a number of
  frequencies.
• Currently, as GSM moves towards third generation
  technology, it is more like a combination of TDMA
  with CDMA.

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What is Wireless? Understanding Cellular

• 3G (Third generation)
• 3G is an ITU (International Telecommunications
  Union) standard for the next generation of
  cellular technology. Designed as a standard over
  and above the second generation technology, 3G
  can work with GSM and CDMA signals. Essentially,
  3G offers a much higher bandwidth than the
  previous technologies, making it possible to do
  things like browsing Web pages directly from the
  Internet (images and all) on a cellular phone, or
  sending images and even small movies over
  cellular networks, from one phone to another.

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What is Wireless? Understanding Wi-fi

• Wi-fi wireless devices operate at a much higher
  wireless frequency than cellular. The exact
  frequency depends on what type of wi-fi
  technology is being used. Wi-fi wireless is also
  intended to be used within a much shorter range
  usually, anywhere from 100 to 500 feet. This is
  mainly due to battery life constraints (most
  wi-fi devices are portable computers or handheld
  devices like PDAs).

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What is Wireless? Understanding Wi-fi

• 802.11...what?

IEEE - Institute of Electrical and Electronics
Engineers. IEEE is an organization of engineers,
scientists, and researchers who develop standards
for the computers and electronics industry
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What is Wireless? Understanding Wi-fi

• The technologies that most people mean when they
  refer to wi-fi are one of the IEEE 802.11
  wireless specifications. Designed mainly for
  wireless local networks, these specifications
  cover technology for making a connection between
  a wireless client and a base station, or two
  wireless devices

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What is Wireless? Understanding Wi-fi

• Versions of 802.11
• 802.11b
• 802.11b is the technology that originally earned
  the moniker wi-fi. It was designed to extend the
  original 802.11 technology specification to
  handle the higher bandwidths (11 Mbps) that
  cable-based local area networks do. It does this
  by using the 2.4 Ghz spectrum, which is the same
  unregulated spectrum used by other devices like
  cordless phones and microwave ovens. The lower
  frequency gives the technology a better range,
  but the bandwidth is limited.

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What is Wireless? Understanding Wi-fi

• 2. 802.11aIEEE
• 802.11a is similar to 802.11b, except that it
  operates in the 5 Ghz spectrum. This frequency is
  more clear of interference, which allows the
  802.11a standard a higher bandwidth of around 54
  Mbps. However, the higher frequency means it
  takes more power to transmit the signal,
  resulting in a shorter range - about half that of
  802.11b.

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What is Wireless? Understanding Wi-fi

• 3. Bluetooth
• Bluetooth was originally developed as a wireless
  alternative to cables, but since then, many more
  uses have been found. Designed specifically with
  handheld devices in mind, Bluetooth operates in
  the 2.4 Ghz spectrum, has very good power
  consumption, and a range of about 150 feet.
• Bluetooth's biggest advantage is that many
  devices can network with each other at once. One
  Bluetooth device establishes what is called a
  piconet, which can include up to eight devices at
  once. Any device in the piconet

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What is Wireless? Understanding Wi-fi

• can communicate with any other connected device.
  So, for instance, the same message could be sent
  from a Bluetooth-equipped computer to up to seven
  PDAs within the broadcasting range.

Cellular and wi-fi are two different
technologies, broadcasting on different
frequencies with different hardware, but the
difference gap in what can be done with these
different wireless technologies is beginning to
narrow.
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Wireless Cellular Phones

• So what can you do with wireless technology?
  That's the big question. Cellular phones were the
  original indispensable wireless accessory, and
  today's phones become more and more versatile
  every day.
• Telephony
• Internet access via cellular phones
• Other wireless phone applications
• WAP
• Cellular Phones in Laptops and PDAs
• Messaging Lingo

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Cellular Phones Telephony

• Believe it or not, cellular phones are still
  capable of the same purpose for which they were
  originally designed making phone calls. Of
  course, the digital technology allows cellular
  phones the capacity to use many of the digital
  services that used to be the sole property of
  land-based lines caller ID, three-way
  conferencing, voice mail, and call waiting, to
  name a few.

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Cellular Phones Internet access via cellular
phones

• More recent, but still a useful service for the
  past few years has been Internet access via
  cellular phones. Access to the Internet via
  cellular networks has progressed through a few
  stages over the years.

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Cellular Phones Internet access via cellular
phones

• Text e-mail
• Many cellular services offered the ability to
  send and receive e-mail messages to an e-mail
  address hosted by the provider. This was useful,
  but the first cellular phones offering this
  service had to rely on the phone's keypads for
  inputting text (difficult with 26 letters and
  only 10 keys), and the displays offered no more
  than one to two lines of text. As well, this
  divided a user's communication, in a time when
  most 'Net-connected people already had at least
  one or more e-mail addresses.

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Cellular Phones Internet access via cellular
phones

• Text Web-browsing
• The introduction of the WAP protocol (see below)
  in the mid 1990s made it possible for cellular
  phones to actually request content from the World
  Wide Web and receive it across the cellular
  network. The problem with this soon became
  apparent since it was hard to compress so much
  text into the tiny LCD screens available at the
  time, and the lack of images made it difficult to
  view certain sites.
• 3G
• Full media Web browsing is now available thanks
  to the faster bandwidth of 3G cellular
  technology. Color LCD screens can display images
  and even animation, and the networks are fast
  enough to download files in acceptable amounts of
  time.

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Cellular Phones Other wireless phone applications

• Games
• Games on cellular phones are probably the next
  big market for cellular technology. Games were
  introduced on mobile phones over the course of
  several waves
• Embedded games
• First came small games that came embedded into
  the cellular phones. These were simple video
  games that users could only play on their phone
  alone, and had no connection with the outside
  world. Essentially, these were bonus features to
  sell the "new" phones with LCD screens (instead
  of a simple numeric LCD).

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Cellular Phones Other wireless phone applications

• SMS-based games
• Although not as popular in the United States as
  they are in Europe and Asia, text games based on
  SMS messaging introduced the first interactive
  elements to wireless phone gaming. Most of these
  types of games were versions of quiz game shows,
  or the long-cherished text-based role-playing
  adventures.
• Java gaming
• The door for cellular phone gaming was opened
  wide with the introduction of a version of the
  Java programming language designed specifically
  for mobile phones. In addition to taking
  advantage of Java's capacity to combine text,
  graphics, and sound, the biggest advantage it
  brings to mobile phones is the ability to
  download Java applications across the cellular
  network. This gives users the potential for
  accessing a huge library of games, or downloading
  larger games in modules.

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Cellular Phones Other wireless phone applications

• Interactivity
• Using SMS messaging, many cellular services now
  offer community aspects to games, such as a
  central server that stores all users' high scores
  for a video game. With Bluetooth chips or
  infrared transmitters, certain brands of cellular
  phones can let two or more users play
  head-to-head or cooperative video games.
• With the faster data transmission available
  thanks to the new 3G technology, cellular gaming
  is poised to become an even larger phenomenon. In
  theory, users will be able to play cooperatively
  or head-to-head on games simultaneously across
  the cellular network, even if they are physically
  located miles apart.

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Cellular Phones Other wireless phone applications

• Text Messaging
• SMS, Simple Message Service , has become an
  integral part of lifestyle for many people,
  especially youth in Europe and Asia. Similar to
  the concept of e-mail, users with SMS-capable
  phones can send text messages across the network
  to other users. An SMS message can be received
  immediately (if the recipient has his or her
  device on), or held like e-mail until the
  recipient connects to get it.

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Cellular Phones Other wireless phone applications

• SMS messages are limited to 160 characters. This
  has prompted a whole vocabulary for SMS messaging
  to evolve, based on the trick of using
  abbreviations and stylized alphanumeric "words"
  to cram as much information as possible into the
  160 characters.
• With the faster transmission speeds of the
  current "2.5G" technology, and the enormous speed
  promised by 3G technology, many models of
  cellular phones are now being created that allow
  transferring of more than just text messages.
  Multimedia Message Service (MMS) allows more
  complex multimedia files (like video) to be sent
  along with a message. MMS allows cellular phones
  equipped with digital camera technology to take
  photos or even short movie clips, and transmit
  them via MMS to other phones equipped with the
  necessary technology to receive and display MMS
  messages.

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Cellular Phones WAP

• WAP stands for Wireless Application Protocol , a
  specification for transmitting data and
  information at high speeds along digital wireless
  technologies like CDMA and GSM. The most popular
  original use for WAP technology was to enable
  cellular phones to browse the Web over the
  cellular network. These "micro-browsers" combined
  WAP for data transfer with HTML to display Web
  content (text only) on the cellular phone's tiny
  LCD display.

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Cellular Phones WAP

• What can you do now with WAP?
• WAP's largest use is still for Internet and
  information services. Text Web browsing, e-mail
  access, and up-to-the-minute stock symbol tickers
  are some of the WAP services that cellular
  carriers currently offer.
• What is on the horizon?
• WAP has recently introduced its second
  incarnation. WAP 2.0 uses a form of XML called
  WML (Wireless Markup Language) for markup display
  on cellular phones. The biggest advantage to WML
  is that content written using the language can be
  easily scaled to fit any device from tiny two
  line, text-only displays all the way to the
  larger graphic screens found in 3G cellular
  phones. WML microbrowsers will be able to display
  color graphics, and is optimized for one-handed
  navigation.

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Cellular Phones Cellular Phones in Laptops and
PDAs

• Not all cellular phones are the type that clips
  onto your belt. Many laptops can be purchased
  that have cellular phones built right in. These
  phones are built to connect to a certain type of
  service (CDMA or GSM, for example), and are
  mainly used as a modem for the computer to dial
  in to Internet Service Providers, or into modems
  connected to corporate networks.
• A good number of PDAs also have cellular phones
  built into the hardware. The phones in PDAs are
  used to connect to specific cellular networks for
  WAP applications like e-mail and Web browsing.
  However, there are also PDAs that include an
  earpiece and a microphone, and have the
  capability of operating as a "real" cellular
  phone, with the operating system taking care of
  details like the dialing of numbers or digital
  call services like caller ID.

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Cellular Phones Messaging Lingo

• f U can rED DIS, U R alredi SMS l33t!
• Did you understand that message? If so, you can
  probably just skip this part right now, since you
  won't be seeing anything you don't already know.
• The text above was an example of some possible
  abbreviations that can be used to shorten a
  message in order to make the most of the 160
  character SMS limit. This type of text messaging
  lingo (also known as "txt") is becoming so
  popular, that some people are claiming that they
  find it easier to write using the shorthand
  lingo. A 13-year old girl in Scotland made
  newspapers worldwide for turning in an essay on
  her summer holidays that was written entirely in
  txt. Upon confronting the girl about it, her
  teacher was astonished to hear that the girl
  found regular English too difficult, and chose to
  use txt because she could express herself better
  with it.

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Cellular Phones Messaging Lingo

• A snippet from the essay
• "My smmr hols wr CWOT. B4, we used 2go2 NY 2C my
  bro, his GF thr 3 - kids FTF. ILNY, it's a gr8
  plc."
• (Translation) "My summer holidays were a complete
  waste of time. Before, we used to go to New York
  to see my brother, his girlfriend and their three
  screaming kids face to face. I love New York.
  It's a great place."
• Transl8it.com
• Transl8it is a Web site that contains, among
  other things, an online translator for
  translating English to txt, and back again. It
  includes a character meter, so you can see how
  many characters you save by using the txt version
  of a message.

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Wireless Wireless for Desktop/Laptop Computers

• WLAN
• Wireless networks security

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Wireless for Desktop/Laptop Computers WLAN

• WLAN (Wireless Local Area Network) is another
  buzzword that sounds very specific, but really is
  a general term to refer to any type of local-area
  networking that uses high-frequency radio waves
  instead of cables to transmit data. The following
  are some examples of WLAN technologies

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Wireless for Desktop/Laptop Computers WLAN

• IEEE 802.11b
• 802.11b, aka Wi-Fi, is probably the most popular
  form of wireless LAN technology. Using a Wi-Fi
  LAN has many advantages
• No need to lay down Ethernet cables. In some
  locations, it can be extremely difficult to
  create a permanent set up for the hardware cables
  necessary to support a LAN. A Wi-Fi network means
  that all a computer needs is to be in range, and
  it can access the network.

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Wireless for Desktop/Laptop Computers WLAN

• Ease of access. Because 802.11b is a global
  standard, it is extremely easy to configure any
  computer (portable or desktop) with an IEEE
  802.11b-compatible network card to access the
  network. Even visitors to an office that has a
  Wi-Fi network can simply sit down and access the
  network with their laptops, with only a small
  amount of configuration.
• 802.11b devices are growing more and more
  common. According to one survey, over 18 million
  WLAN-ready devices shipped in 2002, which was
  over twice the number shipped in 2001. Most new
  laptop computers now come standard with
  integrated 802.11b wireless network interfaces.
• Despite there being faster, more advanced wi-fi
  technologies around the corner (802.11g, for
  example), 802.11b looks like it is here to stay,
  and will probably enjoy several more years as the
  wireless networking standard.

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Wireless for Desktop/Laptop Computers WLAN

• Wi-Fi Hardware
• To establish a Wi-Fi network, you need at least
  two pieces of hardware the wireless access point
  (also called a base station), and the client
  wireless network adaptor.
• Other wireless technologies
• Despite the near universal adoption of 802.11b,
  there are other wireless networking technologies
  being used for wireless LANs.
• Home RF
• Home RF deserves a mention because even though it
  is slower than 802.11b (Home RF bandwidth has a
  maximum of 1.6 Mbps), it is less expensive to
  implement. However, the universal acceptance of
  802.11b has all but pushed Home RF WLAN solutions
  off the shelves.

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Wireless for Desktop/Laptop Computers WLAN

• Home RF
• Home RF deserves a mention because even though it
  is slower than 802.11b (Home RF bandwidth has a
  maximum of 1.6 Mbps), it is less expensive to
  implement. However, the universal acceptance of
  802.11b has all but pushed Home RF WLAN solutions
  off the shelves.
• Other IEEE 802.11 specifications
• IEEE 802.11a has been discussed above as a faster
  alternative to 802.11b, though it has a shorter
  range and is incompatible with 802.11b. IEEE
  802.11g will be next generation of Wi-Fi,
  combining the bandwidth of 802.11a with the range
  of 802.11b. Also, wireless client adaptors are
  being produced now that are dual-mode, meaning
  that they can be switched between 802.11a and
  802.11b (or .11g).

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Wireless for Desktop/Laptop Computers WLAN

• Bluetooth
• While not specifically designed for
  high-bandwidth local area networking, Bluetooth
  is still a decent solution for applications like
  temporary networking devices together for the
  purposes of one-way data transfers (downloading
  Web pages or receiving e-mail), or for
  synchronizing mobile devices to servers on a
  local area network (like a PDA agenda).

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Wireless for Desktop/Laptop Computers Wireless
networks security

• Security is a very real concern when it comes to
  Wi-Fi networks. The very same elements of the
  technology that make it so easy for wireless
  network adaptors to connect to a WLAN also make
  it easier for intruders to force their way onto
  the same networks. On its own, 802.11a and
  802.11b technology has very little security. Most
  wireless access point base stations will work
  right out of the box - but have no security at
  all.
• To keep intruders from connecting to a Wi-Fi
  access point, and taking advantage of other
  computers connected, you need to implement some
  sort of wireless security. 802.1x is an IEEE
  specification for wireless security on 802.11a
  and .11b connections, but to implement it
  requires that your hardware meets the standard,
  and you have software that can enforce it.

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Wireless for Desktop/Laptop Computers Wireless
networks security

• Fortunately, Windows XP has a built-in
  implementation of 802.1x, so creating a secure
  Wi-Fi network with Windows XP is a relatively
  easy task, even for the non-computer savvy.
• The next big thing in security is the IEEE
  802.11i security specification, which is
  scheduled for ratification in 2004. 802.11i will
  establish a type of security called Advanced
  Encryption System (AES), which makes it much more
  difficult for hackers to find the keys needed to
  access a wireless network

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Wireless for Desktop/Laptop Computers Wireless
networks security
A hotspot is anywhere within the accessable
radius of a WiFi network's signal.  

• Warchalking
• Warchalking is the term given to the activity of
  walking (or driving) around public places with an
  open laptop, trying to find unprotected (or
  intentional open) Wi-Fi hotspots. When a
  warchalker finds such a spot, he or she will mark
  it with a particular symbol, indicating to others
  that unprotected wireless access is available at
  that point. This is fine for marking networks
  that are intentionally left open to the public,
  but the additional network traffic that
  recognition of a warchalking symbol can generate
  on an unsuspecting home user's network can be
  staggering.

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Wireless for Desktop/Laptop Computers Wireless
networks security

• Coffeehouse Wi-Fi
• Many businesses, especially bookstores and
  coffeehouses, are providing Wi-Fi Internet access
  in their locations as a way to draw more
  customers. Some of these places offer the access
  for free (such as the NewburyOpen network along
  Newbury St. in Boston), while others charge for
  access to the service like a regular Internet
  Service provider. Starbucks is probably the most
  well-known business to provide Wi-Fi Internet
  access at many of their coffeehouse stores in the
  United States. The service at Starbucks is not
  free, but the price for access is competitive
  with regular Internet access. McDonalds
  Restaurants has announced that it will have
  several hundred restaurants that will offer
  high-speed wireless access by the end of 2003.

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Wireless Wireless for Handheld Computers

• The wireless technologies used in handheld
  computers (PDAs, Pocket PCs, etc.) are more or
  less the same as those used in cellular phones or
  laptops. The key difference is how they're used.

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Wireless Wireless for Handheld Computers

• Internet Access
• Internet access can be achieved on handheld
  computers in a number of ways. The oldest is
  thanks to the cellular modem, connecting to a
  cellular network and accessing Web content with
  WAP-enabled applications. This allows the device
  Internet access anywhere that cellular coverage
  is available, but unless WAP 2.0 and 3G
  technologies have been used, the content is
  probably limited to text.
• More and more handheld computers (like the Pocket
  PC) are being shipped with internal 802.11b
  adaptors. These handhelds can then connect to any
  Wi-Fi hotspot, and use an Internet connection (if
  available).

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Wireless Wireless for Handheld Computers

• Bluetooth, being extremely power-efficient for
  batteries, is another possibility for Internet
  access via a handheld computer. Bluetooth has low
  bandwidth, so for large file downloads it's
  probably not the best solution. But for simple
  connection to a Bluetooth-enabled computer that
  has shared Internet connection for applications
  like Web browsing and receiving e-mail, Bluetooth
  can be a good solution.
• The last two technologies (Wi-Fi and Bluetooth)
  can also be used to access local area networks.
  Bluetooth, in fact, is ideal for syncing PDA
  information with a computer or to a server across
  a LAN.

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Wireless Wireless for Handheld Computers

• Peer-to-peer Connections
• Since very early on, handheld computers have been
  designed to make peer-to-peer connections with
  other handhelds of the same type. Most PDAs come
  standard with an infrared port. Transferring data
  from one PDA to another via the infrared port has
  been nicknamed "beaming". Infrared transfer is
  relatively slow compared to conventional
  wireless-about the same speed as a computer's
  parallel port.
• 802.11b can be used for peer-to-peer connections,
  but once again Bluetooth is probably the best
  solution for handheld devices, thanks to its good
  power consumption rate.

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Wireless Bluetooth

• As introduced earlier, Bluetooth is a wireless
  technology broadcasting in the Wi-Fi spectrum
  (2.4 - 2.5 Ghz) that is ideal for networking all
  sorts of devices together.

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Wireless Bluetooth

• How does Bluetooth work?
• There are two key concepts to understanding
  Bluetooth that a Bluetooth device is always
  listening in a battery-friendly way to establish
  a network connecting with other Bluetooth
  devices, and that Bluetooth devices network
  together in groups of eight called a piconet.
• Establishing the Connection
• When not actively part of a network, a Bluetooth
  device will stay in standby mode (consuming next
  to no power), but will "wake up" every few
  seconds to listen for invitations to join a
  network. This means that a Bluetooth device in
  standby mode really consumes very little power.
• When the Bluetooth device hears an invitation to
  start a connection, it becomes the "slave" to the
  "master" device that initiated the connection,
  and a piconet is formed. The master device in a
  piconet still occasionally looks for other
  Bluetooth devices in its range, to let them know
  they can join the piconet.

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Wireless Bluetooth

• Piconet Communications
• A piconet has a limit of eight Bluetooth devices,
  including the master, but there are ways to get
  around this limitation and allow more Bluetooth
  devices to take part in the network.
• First, any device in a piconet can park itself,
  where it still listens to the piconet traffic (so
  it can jump back in if space is available), but
  isn't actually communicating with the piconet.
• Secondly, two or more piconets can be joined in
  what is called a scatternet. A device in one
  piconet may also exist as part of another piconet
  and may function as either a slave or master in
  each piconet. The advantage to this is that data
  can be sent from a device in one piconet, through
  the shared device, to a device on the second
  piconet.

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Wireless Bluetooth

• What can you do now with Bluetooth?
• Bluetooth had a rocky start, and took a while to
  get established. Only now are more devices being
  made available that truly take advantage of
  Bluetooth for versatile networking. Here are just
  a few examples of what you can do with existing
  Bluetooth devices.

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Wireless Bluetooth

• Cable-free office
• Bluetooth-enabled keyboards and other input
  devices exist. By using Bluetooth, these devices
  become compatible with many types of devices they
  previously could not have been joined to. For
  example, a Bluetooth keyboard could broadcast to
  a desktop computer when in the office. But the
  same keyboard could also be connected to a
  handheld computer, to make it easier to type text
  directly to the device. Bluetooth headsets (two
  earphones and a microphone) can also be used to
  connect with a variety of devices. The same
  headset can be used to transmit voice between a
  telephone connected to a land-based line, to a
  cellular phone, or even to other Bluetooth
  headsets

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Wireless Bluetooth

• Synchronizing data
• The same handheld computer with Bluetooth
  technology can be synchronized to a laptop
  computer, another handheld, a desktop computer,
  or a cellular phone. With a collection of
  Bluetooth devices, you can always take the same
  address book or agenda anywhere with you,
  regardless of what device you have.
• Universal remote control
• Many mechanical devices can also be equipped with
  Bluetooth. Cars can be enabled with Bluetooth to
  be started from Bluetooth devices, or with the
  right technology, you can initiate a cellular
  phone call on a Bluetooth phone with controls
  from the dashboard of a car.

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Wireless Bluetooth

• Universal remote control
• Many mechanical devices can also be equipped with
  Bluetooth. Cars can be enabled with Bluetooth to
  be started from Bluetooth devices, or with the
  right technology, you can initiate a cellular
  phone call on a Bluetooth phone with controls
  from the dashboard of a car.

Wireless encompasses many types of devices and
many brands of technology, but the trick to
sorting through it all is to know exactly what
you need touse the technology for, then
branching out from there. There's a best
wireless solution for all computing needs. Now
that you know your technology, all that's left
is to find it.
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• My references
• Saad.alkhtani_at_yahoo.com
• Ebt_2000_at_hotmail.com