Sara Saad Al-Qahtani 427201054 Ebtissam Al-Motairy 427202249 Section :2518 Time :(8-9) English 104

1. Sara Saad Al-Qahtani 427201054 Ebtissam Al-Motairy 427202249 Section :2518 Time :(8-9) English 104

2. Wireless

3. WirelessWhat is Wireless? The purpose of this guide is to identify the concepts of wireless technology and how to use it effectively. The wordwirelessis 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.

4. WirelessWhat 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.

5. WirelessWhat is Wireless? • Understanding Cellular • Understanding Wi-fi

6. 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.

7. 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.

8. 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.

9. 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.

10. 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 Accessis 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).

11. 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.

12. 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.

13. 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).

14. 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

15. 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

16. 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.

17. 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.

18. 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

19. 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.

20. 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

21. 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.

22. 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.

23. 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.

24. 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.

25. 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).

26. 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.

27. 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.

28. 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.

29. 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.

30. 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.

31. 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.

32. 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.

33. 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.

34. 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.

35. WirelessWireless for Desktop/Laptop Computers • WLAN • Wireless networks & security

36. 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

37. 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.

38. 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.

39. 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.

40. 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).

41. 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).

42. 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.

43. 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

44. 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.

45. 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.

46. 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.

47. 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).

48. 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.

49. 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.

50. 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.