WiFi Basics For some reason, most companies like to overly complicate technology and WiFi is no different. The alphabet soup of acronyms, combined with the ever-increasing avalanche of wireless jargon and gadgets, is quite overwhelming




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About WiFi




WiFi Basics

For some reason, most companies like to overly complicate technology and WiFi is no different. The alphabet soup of acronyms, combined with the ever-increasing avalanche of wireless jargon and gadgets, is quite overwhelming. Maybe it makes them feel smart. If you’re just looking to use WiFi and aren’t looking to become a certified engineer, WiTopia is here to help you. Here’s the short and sweet:



Background : How it all began.

In June 1993, the IEEE, the world’s preeminent information technology standards organization, with over 360,000 members in 175 countries, ratified the 802.11 standard. This is why the types of WiFi are known as 802.11b, 802.11g, and so on. We know this technology more commonly as Wireless Fidelity or “WiFi.”

Nobody really seemed to notice or care until Apple released their AirPort™ WiFi products in 1999 which integrated 802.11 technology with a computer operating system. Soon thereafter, many other vendors such as Linksys, Belkin, and D-Link, to name just a few, began churning out consumer WiFi gear at an incredible rate.

As people started using WiFi at home, and wireless hotspots began to sprout here and there, it was clear we were all becoming hooked. By 2003, the proliferation was out of control and growing exponentially. Today, millions of wireless access points (APs) are sold annually and hundreds of thousands of wireless hotspots have emerged worldwide. We’re all learning fast there’s a tremendous amount of freedom, convenience, and productivity packaged up in that little wireless access point.



How it Works : If you use a cordless phone you already understand WiFi.

WiFi is radio technology and is quite analogous to a cordless telephone in function. Your wireless access point (AP) is the base station and your laptop is the handset. WiFi even uses the same slice of the electromagnetic spectrum (2.4-5.8Ghz) as most modern cordless telephones. This is why you may experience interference between your cordless phones and your wireless network depending on the type of AP and phones you use. All you really need to know is that this spectrum is unlicensed which, in radio terms, means it’s free—a very good thing.



The Flavors : Making sense of the standards.

802.11a -- Not widely in use. Data speeds up to 54Mbps with practical indoor ranges of 25-75 feet. Uses less crowded 5Ghz band with more available channels so it’s good for eliminating interference with high user density or for media streaming.

802.11b -  Most popular but quickly becoming obsolete. Data speeds up to 11Mbps with practical indoor ranges of 75-100 feet. Uses potentially crowded 2.4Ghz band so it’s susceptible to interference from microwave ovens, cordless phones, and neighboring wireless networks.

802.11g – Rapidly growing in popularity. Increased data speed of 54Mbps versus 11Mbps of 802.11b with practical indoor ranges of 75-100 feet. Backwards compatible with 802.11b devices at 11Mbps. Uses potentially crowded 2.4Ghz band so it’s susceptible to interference from microwave ovens, cordless phones, and neighboring wireless networks.

Note: The existence of an 802.11b device within an 802.11g network typically defaults the entire network to a much lower data speed.

802.11nNot standardized yet by IEEE but a number of “Pre-N” APs are available. Uses new MIMO (Multiple Input Multiple Output) technology to achieve vastly improved and consistent data speeds of 108Mbps with practical indoor ranges of several hundred feet. Backwards compatible with 802.11b and 802.11g. MIMO technology eliminates most interference issues.

Why it’s Cool : The future is knocking on your door.

Other than the obvious benefits of being wireless at home, at work, or at a wireless hotspot, WiFi can add some 21st century panache to your life. Stream your music and media collection throughout your home, set up the ultimate gaming environment, build out a camera network, or even implement a home automation system to monitor and control your home from any room or over the Internet.  With WiFi, all this, and more, is now possible.



Security Concerns : With love comes sacrifice.

Chances are, your home wireless network is completely insecure.  That wireless hot spot probably is too. In a perfect world that wouldn’t matter, but the world isn’t perfect is it?

The overwhelming majority of consumers and small businesses are using WiFi with absolutely no security enabled. Even those technical enough to set up the built in security features are reading everyday that they’re still easily susceptible to hackers and many other unsavory things.

A wireless access point is, after all, a miniature radio station broadcasting an open invitation to all who care to snoop your data, or worse. The practice of detecting and cataloging unprotected wireless networks on the Internet is called “Wardriving” and it’s become a virtual sport easily performed by anyone with a wireless laptop and some downloadable tools, and seemingly, a lot of free time. Amusing as this may be it’s more popular than you’d ever imagine#151;which ain’t a good thing any way you look at it.

WiTopia can fix all that for you. With our products, services and knowledgeable staff, you can build your own “wireless utopia” where you can enjoy all the benefits of WiFi with none of the worry.

The How and Why of Wi-Fi

January 28, 2006

What is Wi-Fi?
Simply put, Wi-Fi is freedom. Wi-Fi allows you to connect your computer, PDAPersonal Digital Assistant. Smaller than laptop computers but with many of ... See Glossary

or other devices to each other - all without the expense of cumbersome cables. Imagine working on your laptop or checking e-mail from anywhere in your home or office. Imagine being able to connect to your office network from an airport or coffee shop. Imagine retrieving files or presentations from the corporate network, cruising the Internet or sending instant messages to co-workers - and doing it all from a conference room or the company cafeteria. Now, imagine doing all these things easily and quickly - without worrying about finding a wired network connection. That is Wi-Fi.


How does Wi-Fi technology work?
Wi-Fi networks use radio technologies called IEEEInstitute of Electrical and Electronics Engineers. A global technical profe... See Glossary 802.11aAn IEEE standard for a wireless network that operates at 5 GHz with rates u... See Glossary

, 802.11bAn IEEE standard for a wireless network that operates at 2.4 GHz with rates... See Glossaryor 802.11gAn IEEE standard for a wireless network that operates at 2.4 GHz Wi-Fi with... See Glossary

to provide secure, reliable, fast wireless connectivity. A Wi-Fi network can be used to connect computers to each other, to the Internet, and to wired networks (which use IEEE 802.3The standard defining wired Ethernet networks. (See Ethernet). See Glossary

or EthernetThe most popular international standard technology for wired Local Area Net... See Glossary). Wi-Fi networks operate in the unlicensed 2.4 and 5 GHz radio bands, with an 11 MbpsMegabits per second. A measurement of data speed that is roughly equivalent... See Glossary

(802.11b) or 54 Mbps (802.11a) data rate or with products that contain both bands (dual band). They can provide real-world performance similar to the basic 10BaseTThe most common cabling method for Ethernet. 10BaseT conforms to IEEE stand... See Glossary wired Ethernet networks.

Is Wi-Fi for Me?
Everyone can use Wi-Fi, almost everywhere in the world. Home Wi-Fi networks can connect multiple computers to each other, to peripherals, and to the Internet via a single high-speed connection. A Wi-Fi network can connect a family's computers together to share such hardware and software resources as printers and the Internet. That means everyone in the family can share stored files, photos and documents
and print them out on a single printer attached to one desktop computer - all without unsightly cables running throughout the home.

Is Wi-Fi for my business?
Large corporations and campuses use enterprise-level technology and Wi-Fi CERTIFIED™ products to extend standard wired Ethernet networks to public areas like meeting rooms, training classrooms and large auditoriums. Many corporations also provide wireless networks to their off-site and telecommuting workers to use at home or in remote offices. Large companies and campuses often use Wi-Fi to connect buildings.

Wi-Fi networks also work well for small businesses, providing connectivity between mobile salespeople, floor staff and behind-the-scenes finance and accounting departments. Because small businesses are dynamic, the built-in flexibility of a Wi-Fi network makes it easy and affordable for them to change and grow.


What if I'm away from my Wi-Fi network?
Wi-Fi networks can be found in public places like coffee shops, hotels, airport lounges and other locations. This may be the fastest-growing segment of Wi-Fi service, as more and more travelers and mobile professionals clamor for fast and secure Internet access wherever they are. To find a hotspot point near you, visit the Wi-Fi ZONEA certification program of the Wi-Fi Alliance® that allows users to easily ... See Glossaryat www.wi-fizone.org.
Is it hard to add more users to a Wi-Fi network?
Adding a wireless computer to a Wi-Fi network is easy. There's no need to purchase or lay more cable or find an available Ethernet port on your hub or router. Just plug in your card or USBA high-speed bidirectional serial connection between a PC used to transfer ... See Glossaryconnection, turn on your computer and you're surfing the Net. If your business grows and you need to move, you don't have to abandon your network infrastructure investment or hire a networking company to rewire the new location. And there's no network downtime - you can be up and running even before the furniture arrives. Simply plug the system into a power outlet and you'll be operational in minutes.
Why should my products be Wi-Fi CERTIFIED™?
Your Wi-Fi devices will have the best chance of working together if they are Wi-Fi CERTIFIED™. Look for the Wi-Fi CERTIFIED™ logo with color-coded Standard Indicator Icons (SII) on product packaging or search through our Web site listing of Wi-Fi CERTIFIED™ products before making a Wi-Fi purchase. The Wi-Fi CERTIFIED™ logo is your only assurance that a product has met rigorous interoperability testing requirements to ensure that compatible products from different vendors will work together. The color-coded Standard Indicator Icons or "SII" displayed with the logo will assist you in selecting products that are interoperable. Products displaying the same SII on their packaging are certified to work together

The Wi-Fi Guide for Sales Professionals



January 28, 2006

What is Wi-Fi?
Wi-Fi is a radio technology that networks computers so they connect to each other and to the Internet without wires. Users can share documents and projects, as well as an Internet connection among various computer stations, and easily connect to a broadband Internet connection while traveling. By using a Wi-Fi network, individuals can network desktop computers, laptops and PDAs and share networked peripherals like servers and printers.
A Wi-Fi network operates just like a wired network, without the restrictions imposed by wires. Not only does it enable users to move around and be mobile at home and at work, it also provides easy connections to the Internet and business networks while traveling.
What are the obvious benefits of going wireless?
Wi-Fi provides freedom: freedom to physically move around your home or business and still stay connected to the Internet or local network; freedom to grow and move an office or business without having to install new cables and wires; freedom to be connected while traveling and on the road. Wireless hotspots (airports, hotels, coffee shops, convention centers and any other place where someone can connect to a wireless network) are being installed worldwide. This means Wi-Fi truly does provide unprecedented freedom. Plus, it is cool, and it is fun - as those in the know say, "Once you go wireless, you will never want to use a cable again."
Why would your customer want to use a wireless (vs. a wired) network?
There are real and measurable benefits to using a wireless network versus a standard wired network. For a home installation customer, the greatest benefit is that there are no wires needed: you don't need to drill holes in walls and floors; you don't need to drag cables across the room or hide them under rugs. One Wi-Fi access point can provide network access for any typically sized home. And if you live in a rental or a historical building, you may not be allowed to drill holes - that makes wireless your only solution.
For the manager of a small business or office, wireless makes it easy to add new workstations without having to run additional cables or expand the size of the router. In addition, if someone wants to change his or her office around, you don't need to be concerned about rerouting data cables - just move the furniture and cables, power up the computer, and the employee is back on the network.
For owners of a rapidly growing or seasonal business, using a wireless network provides for quick set up and easy expansion - whenever it is needed. And moves to a different or larger location are fast and simple - just unplug your wireless network and computers and plug them in at the new location. Wireless networkDevices connected to a network using a centralized wireless access point. (... See Glossary users never have to leave their networking investment behind.
Finally, for business owners and managers, extending the network to temporary contractors and guests is easy. Increasingly, mobile users bring their own Wi-Fi computers with them and can easily access email and the Internet via a Wi-Fi network.

How does Wi-Fi compare to other "no-new-wires-needed" solutions?
There are other "no-new-wires-needed" solutions on the market which are primarily targeted to home applications. But none provide the reliability and flexibility of radio-based Wi-Fi.
The main contenders are HomePNA, which uses a home's existing telephone wires as a network, and PowerPlug, which uses a home's power lines. Obviously, neither of these solutions enables you to use mobile computing devices or laptops. In addition, neither provides a solution for people who want to work outdoors, on the patio or in the backyard, or even at the neighbor's house.
HomePNA, which relies on telephone jacks, is limited to those locations in your home where there is an available phone jack. In addition, the phone circuits have to be connected. A home with several different incoming phone lines can be quite problematic, as can "amateur" phone cable installations. PowerPlug installations are more convenient than HomePNA because there are many power connections scattered throughout every room in a house. Unfortunately, large appliances cycling on and off, as well as transformers and surge protectors, can create serious interference.
In the past, HomePNA and PowerPlug network systems were cheaper than Wi-Fi, but this is no longer true: Wi-Fi is now the leader in affordability, as well as in interoperability, performance and mobility.
How compatible is Wi-Fi equipment from different manufacturers?
If it says Wi-Fi, which means it is Wi-Fi CERTIFIED™, it has been tested for interoperability with other Wi-Fi CERTIFIED™ products. The Wi-Fi Alliance tests and certifies each brand and model to ensure it meets strict technical standards and is interoperable with all other Wi-Fi CERTIFIED™ equipment.
How does someone set up a home or office Wi-Fi wireless network?
What equipment is needed to set up a home or office Wi-Fi wireless network?
There are just two basic components of Wi-Fi networks - a base station and Wi-Fi radios in computers. The base stations are commonly called either "access points" or "gateways," and they act as traffic cops between the various connected devices.
Base stations also provide a connection between the network and the Internet. Most base stations can connect directly to a cable or a DSLDigital Subscriber Line. A dedicated digital circuit between a residence or... See Glossary modem. Some have cable/DSL modems built in. Some even have 56K modems built in so that they can connect to the Internet via a dial-up connection.
Laptop computers and PDAs can use either embedded Wi-Fi radios (built into the computer) or standard radios that slide in and out of an open PC CardA removable, credit-card-sized memory or I/O device that fits into an expan... See Glossary slot. Some PDAs and handheld computers can use Wi-Fi radios in other formats like PCIPeripheral Component Interconnect. A high-performance I/O (input/output) co... See Glossary /ISAA type of internal computer bus that allows the addition of card-based comp... See Glossary bus or a USBA high-speed bidirectional serial connection between a PC used to transfer ... See Glossary radio that simply plugs into one of the available USB jacks.
How secure is a Wi-Fi network? How do users ensure that others don't intercept their messages?
Basic wireless networking security is as simple as turning it on: enable WPAWi-Fi Protected Access. An improved security standard for wireless networks... See Glossary to protect data flowing between the Wi-Fi radios and the base station. Other basic techniques include changing the default password and network name, as well as "closing" the network to outside connections. All manufacturers include these instructions for their specific equipment with their documentation. In addition, there are other readily available security measures that make wireless networks almost impenetrable.
Can anything interfere with Wi-Fi radio signals?
Wi-Fi equipment operates in the 2.4 GHz radio band which is the same frequency range as microwave ovens and cordless phones. Interference is not very common, and when it happens it is usually not very serious. When a Wi-Fi system encounters interference, it doesn't turn off - it just slows down a bit. There are various ways to handle interference, such as simply separating the devices, changing a Wi-Fi network's operating channel (there are 11 different channels to pick from) or using Wi-Fi equipment that includes special protocols to reduce interference.
What's the future for Wi-Fi?
Wi-Fi use is growing fast in homes, public access areas and businesses - both large and small. The Wi-Fi Alliance is active with many industry organizations and is working closely with manufacturers to make sure that existing Wi-Fi gear is compatible with wireless technologies developed in the future.

Windows Tips and Techniques for Wi-Fi Networks



It's easy to connect your Wi-Fi® network to computers running Microsoft Windows. In this section we'll discuss the basics of what you need to know to set up and configure your network. Throughout, we'll point you to detailed information and directions on how to implement your network in the various Windows operating systems. The information presented here is intended to provide a basic understanding of the things you will need to consider to make your network useful and secure.
Types of Wireless Networks
There are only two types of wireless network implementations. While they are variously referred to as hosted vs. peer-to-peer, infrastructure vs. ad-hoc, and managed vs. unmanaged, all of these sets of terms are synonymous and represent the same two types of networks. For simplicity's sake, we'll use the terms "hosted" and "peer-to-peer" because those terms are more descriptive of their function in a small SOHOThe term describes an office or business with ten or fewer computers and/or... See Glossary(Small Office or Home Office) network, which is our main focus.
A "hosted" network contains one or more separate access points connected directly to an existing network. These access points are called "gateways" or "wireless routers." This configuration allows wireless devices to access the computers on the existing network, as well as the peripherals and services available on the network such as printers, Wide Area Networks ( WANWide Area Network (WLAN). A data communications network that spans large lo...

See Glossary) or the Internet.
A "peer-to-peer" network consists only of devices connected wirelessly. A peer-to-peer network contains no central access point or controller, which means each device communicates directly with the other wireless devices in the network. In this configuration, one device can share the information and services available on another device. For example, you could sit by the pool with your laptop, wirelessly surfing the Internet through the DSLDigital Subscriber Line. A dedicated digital circuit between a residence or... See Glossary service connected to your desktop computer inside your home office. For this configuration to work, both computers must be turned on.
In corporations or enterprises, more than one hosted network may be connected. In this complex environment, wireless connectivity can be accomplished in many ways. We recommend that the IT department that manages the network always implement this type of connection - not only because the possibilities are too numerous to present here, but also because most IT departments are already equipped to handle wireless connections.
Microsoft Networking Basics
If you are using Windows 2000 or Windows XP, the basic installation procedure may be as simple as powering down the computer and peripherals, installing the Wi-Fi hardware and rebooting the systems. However, if you are adding Wi-Fi equipment to an existing wired LANA system of connecting PCs and other devices within the same physical proxi... See Glossary

or if you want to change things after you install your Wi-Fi system, you need to know a few basic concepts. You can find more detailed information and procedures in the "Help" section on the Windows "Start" menu.


Your place on the network
Most networking tasks can be completed from "My Network Places" on the "Start" menu. Here, in the "Network Tasks" menu, you can add a network place, view network connections, set up a small network or view other computers in your local network. You will use this menu frequently to access resources on other computers and change network settings.
Naming your network and computers
Each computer must be able to identify the other computers on the network. Since each computer could be a part of several networks, it must be able to identify each network as well. The principle is simple: the network name must be the same for every computer using the network, and each computer on the network must have a unique name so that other computers can find it. If you want your Wi-Fi equipment to access the computers, peripherals and services on your existing network, you must use the same network name when you set up your Wi-Fi system.
To find out the network and computer name, choose "Control Panel" from the "Start" menu. Click on "System" and then choose the "Computer Name" tab. You can change your network and computer names from here as well.
Finding computers, files and services on the network
Computers can connect or disconnect from a network. To find out which computers are currently connected to your network, choose, from the "Start" menu, "My Network Places." Under "Network Tasks," choose "View Workgroup Computers." This will show you all of the computers currently on your Local Area Network. To find out which files and services you can share on a listed computer, click on its name. Clicking on individual drives, folders, files, printers or other devices provides direct access to them as if they were on your computer. This works just like the "Windows Explorer" feature, so you can keep clicking to get continued access as you go deeper into the file structure.
Sharing information
When you look for files and services on another computer, you will probably find that you cannot access every drive, folder, file, printer or other device on the computer. You may not want other computers on the network to have access to all of your resources, either. You control which resources to share. To share resources, start in Windows Explorer and bring up the folder directory. Then, right-click on any drive or folder on your computer. Choose the "Sharing" or "Sharing and Security" option, and then click on the "Sharing" tab. Here you can choose whether or not to share the information. You can also add a password to protect the data if you choose to share it. In order to share a file or folder, you must also share the folders and drives above it in your computer's file system.
Printers may also be shared by right-clicking on a printer in the "Printers and Faxes" section under "Settings" or "Control Panel" and choosing the "Sharing" option and the "Sharing" tab.
A map to frequently used data
You may find that you require frequent access to files on another computer. You can get easier access to those files by "mapping" them so that they appear to be contained in a drive on your own computer. You will see the "mapped" drive in "My Computer" and in Windows Explorer.
You can begin the mapping process from "My Computer" or Windows Explorer by choosing "Map Network Drive" from the "Tools" menu. Or, you can right-click "Map Network Drive" from "My Network Places" on the "Start" menu. Follow the instructions to select a drive letter and browse the network for the data you want to assign to that drive. Please note that if the computer you are connecting to is not on the network when you are trying to reach it, or if the file is in use by another computer, you will not be able to access the data.
Consult the wizard
Windows contains a number of wizards that can walk you through each step in setting up, troubleshooting or making changes to a network.
You can have Windows help you through the entire procedure of setting up a network for a small office or a home. From "My Network Places," and "Network Tasks" choose "Set Up a Home or Small Office Network" (alternately called "Network Setup Wizard") in the "Network Tasks" menu.
To troubleshoot your network in Windows XP, from "My Network Places," and then "Network Tasks"
click on "View Network Connections," then from the "See Also" menu select the "Network Troubleshooter" wizard. There are other wizards that you may find useful within the help section on the "Start" menu. Search for a specific topic and links to applicable wizards will be found within the text.
There can be only one master: IPInternet Protocol. The basic communications protocol of the Internet. (See ... See Glossary

addresses, NATNetwork Address Translation. A network capability that enables multiple of ... See Glossary and DHCPDynamic Host Configuration Protocol. A protocol for dynamically assigning I... See Glossary

To communicate with other computers on the Internet, your computer must have a unique, identifiable address that other computers on the Internet can recognize so they can send it information. This can be accomplished in several ways.


Using an IP (Internet Protocol) address is the traditional way to make your computer identifiable to others on the Internet. An IP addressInternet Protocol address. IP Version 4, the most widely used Internet prot... See Glossary

consists of four sets of (up to) three digits separated by decimal points. They look like this: 555.555.555.555. Large networks have blocks of these addresses that they assign to the computers on their local networks.


Small office and home networks may use DSL or cable access to the Internet. Typically, this type of access only includes a single IP address. So if you want to connect several computers to the Internet through these services, you need to assign different identities to each of your computers.
For SOHO users, NAT (Network Address Translation) is the way to assign separate computer identities to individual computers that connect to the Internet using a single IP address. The NAT service is usually provided by a "router" or "gateway" that goes between the Local Area Network and the Internet. It keeps track of each computer and routes the correct data to it even though it doesn't have its own individual IP address directly assigned to the Internet. Sometimes this device also provides firewall services to help protect the data on the computers from hackers trying to gain access through the Internet.
For most applications, computers are assigned an address by the router or gateway as they are turned on or plugged into the network. The router assigns these addresses "on the fly," using a protocol called DHCP (Dynamic Host Configuration Protocol).
When setting up your Wi-Fi network, you need to know that only one DHCP device can operate on the network. If you are installing a Wi-Fi gateway that provides DHCP directly between your computer and the Internet, there should not be a problem. However, if you are installing a Wi-Fi gateway on an existing network that already contains a DHCP router between the network and the Internet, you must make sure to turn off the DHCP function in the Wi-Fi gateway.
It's easy to determine if a computer on an existing network is set up with IP addresses or DHCP. Select "My Network Places" from the "Start" menu. Under "Network Tasks," click on "View Network Connections." Double-click on the "Local Area Connection" icon. This will show the "Local Area Connection Properties" window. Select "Internet Protocol" on the "General" tab and click on the "Properties" button. If the computer is using DHCP, the box next to "Obtain an IP Address Automatically" will be checked. If an IP address has been assigned directly to the computer, you will see the box next to "Use the Following IP Address" checked, along with the addresses assigned to the computer.
Before You Begin
How you install and secure your wireless system depends on which Windows operating system you are using. No matter which system you have, you should make sure that it has been updated to the latest version and that all applicable security patches have been installed. To check if your system is current, you can access the "Windows Update" feature through the "Start" menu or go to the Windows Update Web Site at windowsupdate.microsoft.com.
Be sure to read the documentation that came with your wireless equipment for detailed directions and to make sure your equipment is compatible with the operating system you are using. Check your manufacturer's Web site to make sure you have the latest drivers for your equipment and Windows operating system. If you are using Windows XP you may not need drivers, but it's a good idea to make sure.
Windows Operating Systems Before Windows 2000 or Windows XP
Wi-Fi can be installed on nearly any Windows system including Windows 98, Windows Me, Windows NT, Windows 2000 and Windows XP. (Win 95 is problematic with Wi-Fi networks.) Make sure the equipment you choose is compatible with your operating system.
Windows 2000 and Windows XP can automatically detect and help configure your Wi-Fi equipment because many of the important drivers are already built in.
Previous versions of Windows require device-specific drivers. Wi-Fi equipment manufacturers supply these drivers along with detailed instructions on how to install the equipment for each operating system. Be sure to follow these instructions carefully to assure a successful connection.
If you are installing an access point on an existing LAN, be sure that the network is operating correctly before installation.
Windows 2000 and Windows XP
These operating systems were specifically designed to be compatible with Wi-Fi. If you have Windows 2000, be sure to upgrade to the latest Service Pack to take advantage of all Wi-Fi features.
If your Wi-Fi hardware is compatible with your operating system, just turn off your computer, install the hardware and boot up the computer again. Your operating system will detect and install your Wi-Fi equipment, and a wizard will launch to help you configure it. Be sure to read the documentation that comes with your Wi-Fi equipment so you will be ready for the questions the wizard will ask. Any drivers or software provided by the manufacturer should be on hand.
If you are using Windows XP or Windows 2000 (SP2 or later) and your Wi-Fi card is connected to your computer, an icon will appear in the system tray (Under "Start", "My Network Places", "View Network Connections") that looks like a computer with a small vertical antenna. It's called the Wireless LAN Configuration Utility. You can click with your left mouse button at any time to check the status of the connection and adjust the configuration.
Windows XP has a "Zero Configuration" feature that makes Wi-Fi installation so simple your system may install everything without bothering you at all. It's possible that all you'll need to do is power down your computers, install the Wi-Fi cards, power up again and watch while the system configures itself.
Windows XP also will automatically detect any open or available Wi-Fi networks in the area, provide a list and allow you to connect.
Then, if your desktop computer was connected to the Internet, you could take a walk with your laptop to check your e-mail, surf the Net or read the latest news on your patio, upstairs or even across the street in that little neighborhood park.
Before you do, ponder this: anyone who installs a Wi-Fi card within transmitting distance can now gain access to your computer and all its services, including your Internet service. That's why at this point you need to think seriously about security. But don't worry - setting up a secure Wi-Fi connection requires only a few more steps.
Security
This is a brief overview of Wi-Fi network security issues. For more detailed security techniques, search Securing Your Wi-Fi Network and Secure Wi-Fi.
Remember that Wireless LAN Configuration Utility that resides in your system tray ("Start," "My Network Places," "View Network Connections"). Left-click on it and you'll see almost everything you'll need to make your system more secure in the window that pops up. Here's a checklist of some things you can do to enhance your security:
For all systems

  • Keep your operating system, software and drivers up-to-date with the latest security patches. Get a virus program and use it.

  • Change the SSIDA unique 32-character network name, or identifier, that differentiates one ... See Glossary (Service Set Identifier) - found on the "Configuration" tab -from the default provided by the manufacturer. Change it to something that would be difficult to guess.

  • Enable WEPThe original security standard used in wireless networks to encrypt the wir... See Glossary (Wired Equivalent Privacy), on the "Configuration" tab, with the highest level of encryption your hardware will support. You'll need your equipment manufacturer's instructions if you're installing an access point. The "EncryptionA mechanism for providing data confidentiality. (See 802.11i, RC4, TKIP, WE... See Glossary " tab allows you to create a WEP key pass phrase. This is similar to a password and should be changed from time to time, or immediately if you feel the key may have been compromised. You may be given an option of "open" or "shared" key. "Shared" key is the most secure option, since it performs an authentication check as well as encrypting data.

  • A firewall is recommended for any computer or router that provides direct access to the Internet.
    For Windows
    Any time you open up a computer to use on a network (particularly the Internet), you should think about changing access to some drives, files, directories and services on your computer to enhance security.
    You can turn off sharing of any drive, directory, file or device on a computer. Open up Windows Explorer and right-click on the item you wish to change. A menu will appear. Choose "Properties," then the "Sharing" tab. There you can choose whether or not to share the item. If you choose to share it, you can specify a password that will be required to access the item.
    Some advanced users enhance security by using a different network protocol on their local wired/wireless network. Since the Internet uses TCP/IPThe underlying technology of Internet communications. While IP handles the ... See Glossaryprotocol, the use of IPX/SPX protocol for such functions as file and printer sharing makes it very difficult for a hacker to gain access to these services. This change is not recommended for the faint of heart: it requires changing the protocol on all of your computers, and you'll need administrator access for every computer. Should you decide to try this, begin by clicking on "Network Connections" from the "Start" menu. Here you will install the new IPX/SPX protocol and provide bindings to enable it for use in file and printer sharing.
    Resources
    Windows 2000 and Windows XP both have extensive built-in help sections on the "Start" menu. If you need help, search for "Wireless Networking" or any specific network topic such as "IPX/SPX" and links to several network troubleshooting wizards will appear within the text. If you need more detailed troubleshooting instructions, try Microsoft's "How to troubleshoot wireless network connections in Windows XP": http://support.microsoft.com/default.aspx?scid=kb;en-us;Q313242.
    Microsoft also has a Web site devoted to Wi-Fi. It can be found at www.microsoft.com/windows2000/technologies/communications/wifi/default.asp.
    A final reminder: Don't forget to get the latest information and drivers from your hardware vendor before you begin any Wi-Fi installation.

What RangeThe distance covered by a wireless network or radio device. Depending on th...

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Can You Expect from Your Wi-Fi® Network?
How Far will It Transmit?
Distance from the Base Station
One of the factors that affects range and performance of a Wi-Fi network is the distance of the client devices (your Wi-Fi equipment) to your base station (your access point or gateway). In an open area with no walls, furniture or interfering radio devices, you may be able to get a range of 500 feet or more from your base station to your Wi-Fi equipped computer. In fact, you could get a signal from up to a mile away depending on the antennas you use and environmental conditions!
Many base stations can also act as repeater or relay stations for your network. For example, if you locate one Wi-Fi equipped computer 100 feet away from your base station, another Wi-Fi computer 100 feet away in another direction, and then position your base station in the middle, you can create a network with a range of 200 feet from one Wi-Fi computer to the other.
Wi-Fi, or IEEEInstitute of Electrical and Electronics Engineers. A global technical profe...

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802.11bAn IEEE standard for a wireless network that operates at 2.4 GHz with rates...

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, speed decreases the farther you move from the base station. For example, when you are close to the base station, your Wi-Fi computer should be able to get the full 11 MbpsMegabits per second. A measurement of data speed that is roughly equivalent...



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data rate. Move farther away, and depending on environment, the data rate will drop to 5.5 Mbps. Move even farther, and the data rate will drop to 2 Mbps, and finally to 1 Mbps. But getting just 1 Mbps throughput is still a perfectly acceptable performance level. 1 Mbps is faster than most DSLDigital Subscriber Line. A dedicated digital circuit between a residence or...



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and cable connections, which means it's still a satisfactory high-speed transmission if you're sending and receiving e-mail, cruising the Internet or just performing data entry tasks from a mobile computer.


Wi-Fi Range Estimates

 


Maximum Range

Range at 11 Mbps

Outdoors / open space with standard antenna

750-1,000 ft

150-350 ft

Office / light industrial setting

250-350 ft

100-150 ft

Residential setting

125-200 ft

60-80 ft

Walls and Other Obstructions
Metal and other dense materials can affect the transmission of radio waves. You can expect that your Wi-Fi system will have difficulty transmitting from one room to another if the walls in your home are composed of, or heavily reinforced with, metal. Stone, brick, heavy woods and even water can also affect range.
What Can You Do to Maximize the Range and Performance of Your Home Networking System?
To improve your Wi-Fi network's range and performance, try experimenting with the placement of your base station, antennas and client devices like laptop computers and PDAs. If you can move your base station and its Internet connection, try different positions around the room. Put your base station and its antenna high up, off the floor and away from metal, power supplies and electrical outlets and wiring. Sometimes just swiveling the antennas or angling your base station can measurably improve range.
It is also possible to add more external antennas to many Wi-Fi networking systems, and they can greatly improve range and performance. A unidirectional antenna can narrow the overall beam width of your base station, providing much improved range. A narrow-beam antenna can enable you to transmit many times the distance of your base station's omni directional antenna's normal range, albeit in just one or two directions instead of transmitting the shorter distance in all directions. You gain greater range for your network but you reduce mobility because your transmissions have narrower coverage.
You can also improve range by turning off or removing electrical appliances that emit interfering radio waves. Some cordless phones, microwave ovens, and radio-operated toy controls operate in the same public 2.4 GHz wireless frequency band as Wi-Fi. You can move the systems farther apart or try to restrict use of interfering devices to times when you're not using your Wi-Fi system. It is also possible to change your Wi-Fi network channel to avoid the channels used by the competing devices. Most Wi-Fi systems use channel 1, 6 or 11 as the default; try switching the channel to 7 or 10.
In addition, some brands of Wi-Fi gear have various proprietary solutions to help reduce interference. Read the instructions for your make and model.




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WiFi Basics For some reason, most companies like to overly complicate technology and WiFi is no different. The alphabet soup of acronyms, combined with the ever-increasing avalanche of wireless jargon and gadgets, is quite overwhelming

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