What is Wi-Fi?
Simply put, Wi-Fi is connectivity. At home, Wi-Fi connects you to your favorite content and communications over your mobile phone, computer, media players and other devices - all without cumbersome cables. When you're on the move, Wi-Fi lets you connect to the Internet or your office from an airport or coffee shop and helps you stay productive when you're away from home. 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 802.11 to provide secure, reliable, fast wireless connectivity. A Wi-Fi network can be used to connect electronic devices to each other, to the Internet, and to wired networks which use Ethernet technology. Wi-Fi networks operate in the 2.4 and 5 GHz radio bands, with some products that contain both bands (dual band). They can provide real-world performance similar to basic wired networks.
Is Wi-Fi for Me?
Everyone can use Wi-Fi, almost anywhere in the world. Home Wi-Fi networks can connect multiple devices to each other, to audio and video content, and to the Internet via a single high-speed connection. A Wi-Fi network can connect a family's computers, media and display devices together to share hardware and media resources such as printers, audio files and Internet access. 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.
Wi-Fi products are easy to connect together. The Wi-Fi Alliance has awarded more than 11,000 product certifications to devices that have been tested for interoperability and to ensure that they are good neighbors to other Wi-Fi equipment. This means that they won't interfere with operation in other products. When you purchase Wi-Fi CERTIFIED products, you can be confident that they have been tested to operate well on your wireless network, and contain the latest security features.
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.
Wi-Fi Technology
Today Wi-Fi products can do everything from sending email to streaming video and linking international video conference calls - even linking you to the Internet from a plane 10,000 feet in the air or just down the hallway. Products for all these needs come in many shapes and forms to meet all your needs, some for as little as a few dollars.
To get where we are today, it has taken a great cooperation between thousands of companies, researchers, and engineers to develop products that work together seamlessly. In the mid-1990s, an international consortium of engineering experts from many technology companies began working together through an organization called IEEE (Institute of Electrical and Electronic Engineers, known as "I-triple E"), to develop industry standards for how these new wireless products should interact with each other. Out of that cooperation, the Wi-Fi Alliance® was born, and has taken those standards and developed test labs around the world to test and certify that products meet the standards of interoperability and security.
Frequency Band
Wi-Fi products operate over radio waves, in the same way as your cell phone, garage door opener, TV, radio, GPS navigation system or microwave. Each of these types of products operate in a specific slice, or frequency band, of the radio spectrum.
Radio Band Examples
- AM broadcast band (530-1610 kHz)
- Shortwave bands (5.9-26.1 MHz)
- Citizens' band (26.965-27.405 MHz)
- Television channels 2-6 (54-88 MHz)
- FM broadcast band (88-108 MHz)
- Wi-Fi (2.4GHz or 5GHz)
Wi-Fi products operate in the 2.4GHz or 5GHz bands. These bands are designated as "license-free", which indicates that individuals may use products designed for these bands without a government license, such as those that are granted to TV or radio transmissions within licensed bands. Because the Wi-Fi bands are "license free", it becomes more important for manufacturers to ensure that their products pass the standards of interoperability set by the Wi-Fi certifications. And because they also share these bands with non-Wi-Fi products, such as remote control toys, certification testing ensures that Wi-Fi products are good neighbors and will not interfere with signals from these devices.
Interoperability
Interoperability means that products from different companies will work together, so users don't get locked into a single brand of Wi-Fi products. Any of the more than 400 Wi-Fi Alliance member companies can submit products for certification, which means that you have a wide variety of choices in products, and can mix-and-match Wi-Fi CERTIFIED products with the confidence that they will work together.
What is 802.11?
Today's Wi-Fi products are designated by a Dewey Decimal-like system, developed by the IEEE to differentiate between various technology families. Wi-Fi products are identified as 802.11, and are then further identified by a lower case letter that identifies which specific technology is in operation, such as 802.11a. Each certification set is defined by a set of features that relate to performance, frequency and bandwidth. Each generation also furthers security enhancements and may include other features that manufacturers may decide to implement.
To date there have been four Wi-Fi generations of products available, and more standards are in the works for adding future features and enhanced performance and security. Each generation is defined by a set of features that relate to performance, frequency and bandwidth. Each generation also furthers security enhancements and may include other features that manufacturers may decide to implement.
Wi-Fi Generations
| Wi-Fi Technology | Frequency Band | Bandwidth or maximum data rate |
| 802.11a | 5 GHz | 54 Mbps |
| 802.11b | 2.4 GHz | 11 Mbps |
| 802.11g | 2.4 GHz | 54 Mbps |
| 802.11n | 2.4 GHz, 5 GHz, | 450 Mbps
|
Wi-Fi CERTIFIED products are tested to ensure that they work with previous generations of Wi-Fi products that operate in the same frequency band. For example, the Wi-Fi CERTIFIED 802.11g designation indicates a product has been certified to meet the standards for 802.11g, and will operate with devices Wi-Fi CERTIFIED for 802.11b or 802.11n (that support 2.4 GHz). This means that as you add new devices to your existing Wi-Fi network, you can be confident that they will work together well.
Wi-Fi CERTIFIED products will contain a logo identifying which features have been tested and that the product has met all the standards of the notation.
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