FAQ

Core Technologies (802.11a/B/G/N Draft 2.0)

What is 802.11b?
802.11b, or IEEE 802.11b, is a standard that has been developed by the IEEE (Institute of Electrical and Electronic Engineers), http://standards.ieee.org. The IEEE is an international organization that develops standards for hundreds of electronic and electrical technologies. The organization uses a series of numbers, like the Dewey Decimal system in libraries, to differentiate between the various technology families.

The 802 committee develops standards for local and wide area networks (LANs and WANs). For example, the 802.3 committee develops standards for Ethernet-based wired networks, the 802.15 group develops standards for personal area networks, and the 802.11 committee develops standards for wireless local area networks (LAN).

802.11 is then further divided: 802.11b, or Wi-Fi, is a standard for wireless LANs operating in the 2.4 GHz spectrum with a bandwidth of 11 Mbps. 802.11a is a different standard for wireless LANs operating in the 5 GHz frequency range with a maximum data rate of 54 Mbps. Another draft standard, 802.11g, is for WLANs operating in the 2.4 GHz frequency but with a maximum data rate of 54 Mbps. Other task groups are working on enhanced security (802.11i), spectrum and power control management (802.11h), quality of service (802.11e),
etc.
What features will the IEEE 802.11n standard offer?
The primary feature offered is speed; IEEE 802.11n offers at least four times, and perhaps eight times, the user data rate of any currently available IEEE 802.11 product.
Are there any 802.11n draft 2.0 products available now?
Yes. Please see the "Certified Products" section of this web site to search for products that are Wi-Fi CERTIFIED 802.11n draft 2.0.
How long does it take to develop an IEEE 802.11 standard?
This varies quite a bit. In the case of the final 802.11n standard, it is not expected to be completed until 2009. Please see the IEEE web site for more information: www.ieee.org.
How will the Wi-Fi Alliance® achieve product compatibility and a good user experience for IEEE 802.11n draft 2.0 products?
This will be achieved through rigorous testing of products that are based on the draft 2.0 of the IEEE 802.11n standard. Consumers should look for the Wi-Fi CERTIFIED™ logo to ensure the best user experience possible.
Can products that were built based on the draft IEEE 802.11n standard be "upgraded" to be compliant with the final IEEE 802.11n standard when it is finalized?
At this time it is not clear whether this would be possible.
How will the Wi-Fi Alliance® feature Extensions Policy apply to products that are currently claiming support for features of the draft IEEE 802.11n standard?
Any product with a feature extension (such as an early feature of the IEEE 802.11n draft standard) that causes severe performance degradation and interoperability issues with another Wi-Fi CERTIFIED™ product can have its certification revoked. The Wi-Fi Alliance® has a formal process for vendors to file grievances. This policy is in place to protect user experience, but at the same time, to allow for innovation and differentiation of products from vendors.
Will 802.11g make 802.11a obsolete? If not, why?
No, ultimately we believe that most products will include both technologies because they are complementary. The fact that they operate in different bands allows them to be used at the same time. This allows 802.11g to complement 11a by adding three additional channels in the 2.4GHz band to the existing 802.11a channels. This creates more network capacity to allow for additional users. Both technologies have advantages that, when used in combination, offer an even stronger product. Another advantage of 802.11a is that the 5GHz base has more capacity around the world. Currently there are 13 channels in North America (including U-NII and ISM bands); 8-19 channels in Europe; and 5-12 channels in Asia. The more channels you have, the more aggregate throughput you can have.
What are the performance differences between 802.11g and 802.11a?
Performance is made of multiple parameters, including:
- Maximum data rate is similar for 802.11a and 802.11g products, using the same OFDM modulation. However, when an 802.11g product is supporting backward compatibility with 802.11b products, the 802.11g network aggregate throughput available for actual data transport will be substantially lower.
- Maximum range is somewhat longer for 802.11g products due to the lower "path-loss" in the 2.4GHz band, compared to the 5GHz band, used for 802.11a products.
- System capacity: 802.11a products offer more channels than 802.11g products, and have the potential to offer higher system capacity.

It should also be noted that these parameters are subject to specific implementation by the different vendors.
Why should I buy Wi-Fi CERTIFIED 802.11n draft 2.0 products?
802.11n is a breakthrough technology that enables Wi-Fi networks to do more, faster, and over a larger area.   802.11n Wi-Fi provides the best connection available for computer networking and home entertainment applications alike - delivering the range, bandwidth, and performance today's multimedia applications and products demand. 

Key features of Wi-Fi CERTIFIED 802.11n draft 2.0 products include:

  • A strong Wi-Fi signal that can blanket the entire home
  • Support for more devices connecting together on a single network without sacrificing bandwidth
  • Use many devices and applications without sacrificing connection performance
  • Plenty of bandwidth to move high-definition video and audio streams from device to device throughout the home
  • The best user experience while using Wi-Fi devices for with voice calls, video games, and other multimedia applications
  • Back up large files in a snap
  • Confidence that devices from different  manufacturers will work together
  • Tested for latest security features
  • Configured with "good neighbor" protocol
How much performance improvement should I expect with 802.11n draft 2.0 Wi-Fi products?

The technology specified in 802.11n draft 2.0 has the potential to deliver up to twice the range and five times the throughput of 802.11a, 802.11b, or 802.11g Wi-Fi devices.  However, products may vary in their performance and you should consult manufacturer information and independent product reviews to determine which products are right for you.

What does “draft 2.0” mean (in reference to 802.11n)?

The IEEE (Institute of Electrical and Electronics Engineers) defines the underlying standards of Wi-Fi technology through a process of written draft documents which are approved by the organization and which ultimately lead to an accepted final standard.  Currently, draft 2.0 of the IEEE 802.11n standard has been approved, and this forms the basis for Wi-Fi CERTIFIED 802.11n draft 2.0 products.  The final 802.11n standard is not expected until 2009, but the draft 2.0 is widely considered to provide a stable foundation for commercial products.

The Wi-Fi CERTIFIED logo includes the word “draft” so that consumers will know that products with the certification are based upon this draft standard.  By looking for the Wi-Fi CERTIFIED logo consumers will know that products have been tested for interoperability, and also that they support the requirements of the same foundational set of specifications.

Will my Wi-Fi CERTIFIED 802.11n draft 2.0-based Wi-Fi product work with products that are Wi-Fi CERTIFIED and designed to comply with the final 802.11n standard?

When the final 802.11n standard is ratified by the IEEE, the Wi-Fi CERTIFIED program will be updated to align with its requirements.  This is expected in 2009.  At this point it is not possible to determine whether “forward compatibility” with the final standard will exist, but it is widely believed that at least some manufacturers will be able to upgrade equipment via a software update.

I’ve seen pre-802.11n products in the store for a while now. What has changed?

Some manufacturers released products based upon earlier versions of the IEEE draft standard and labeled these products “pre-n.”  Some of these products were noted to have interoperability problems. With the Wi-Fi CERTIFIED 802.11n draft 2.0 program, the Wi-Fi Alliance is helping the industry converge on a specific draft version of the standard against which all certified equipment will be tested.

Can I use 802.11n draft 2.0 products with my older Wi-Fi gear?

Yes.  Wi-Fi CERTIFIED 802.11n draft 2.0 products are tested for backward compatibility with Wi-Fi CERTIFIED 802.11 a/b/g products. Users should match the letters on the Wi-Fi CERTIFIED logo for the new product to the letters in the Wi-Fi CERTIFIED logo in their old product(s).

If a product is Wi-Fi CERTIFIED but does not display the logo, you can determine which older Wi-Fi products will work with this equipment by finding out whether the older products operate in 2.4 GHz or 5 GHz (called band or frequency band), and making sure that the Wi-Fi CERTIFIED product(s) you purchase operates in the same band.

What is MIMO?
MIMO is an abbreviation for Multiple-Input Multiple-Output, which refers to the ability of equipment to handle multiple data input and multiple data output operation.  Wi-Fi CERTIFIED 802.11n draft 2.0 devices make use of multiple antennas to send and receive more than one communication signal simultaneously. This is similar to having two FM radios tuned to the same channel at the same time – the signal becomes louder and clearer. This multiplies the performance of the Wi-Fi signal, and is reflected in the two, three, or even more antennas found on some 802.11n access points or routers.
If I have a mixed network of Wi-Fi CERTIFIED 802.11n draft 2.0 and previous-generation Wi-Fi gear, can I still get the benefits of 802.11n?
Wi-Fi CERTIFIED 802.11n draft 2.0 gear is backward-compatible with Wi-Fi CERTIFIED 802.11 a/b/g gear that operates in the same frequency bands.  When using an 802.11n router or access point, you will probably see some performance improvements on a mixed network, but the dramatic range and throughput improvements are only possible when both the client device (notebook computers, gaming devices, printers, cameras, etc.) and access points are Wi-Fi CERTIFIED 802.11n draft 2.0.
Are 802.11n draft 2.0 products protected by security?

Yes. All Wi-Fi CERTIFIED 802.11n draft 2.0 products are tested for the latest generation of government-grade Wi-Fi security: WPA2™ (Wi-Fi Protected Access™ 2). The only way to be sure that an 802.11n draft 2.0 product meets these standards is to purchase Wi-Fi CERTIFIED products. 

I heard 802.11n draft 2.0 can cause interference problems with other Wi-Fi networks. Is this true?
In some configurations, 802.11n draft 2.0 products can interfere with other Wi-Fi networks when these 802.11n draft 2.0 products are trying to achieve the best performance.  However, all products that are Wi-Fi CERTIFIED 802.11n draft 2.0 are required to implement a “good neighbor” protocol that helps ensure interference is not a problem.  This is another important reason to buy only Wi-Fi CERTIFIED 802.11n draft 2.0 equipment.

Background

What does the Wi-Fi Alliance® Do?
As a nonprofit trade organization, the Wi-Fi Alliance® has three purposes: To promote Wi-Fi worldwide by encouraging manufacturers to use standardized 802.11 technologies in their wireless networking products; to promote and market these technologies to consumers in the home, SOHO and enterprise markets; and last but certainly not least, to test and certify Wi-Fi product interoperability.
How do Wi-Fi and WiMAX relate?
Wi-Fi and WiMAX will coexist and become increasingly complementary technologies for their respective applications. Wi-Fi technology was designed and optimized for Local Area Networks (LAN), whereas WiMAX was designed and optimized for Metropolitan Area Networks (MAN). WiMAX typically is not thought of as a replacement for Wi-Fi. Rather, WiMAX complements Wi-Fi by extending its reach and providing a "Wi-Fi like" user experience on a larger geographical scale. In the 2006-2008 timeframe, it is expected that both 802.16 and 802.11 will be available in end user devices from laptops to PDAs, as both will deliver wireless connectivity directly to the end user - at home, in the office and on the move.
Is the Wi-Fi Alliance® concerned with other wireless service technologies?
The Wi-Fi Alliance® is involved in next-generation wireless networking technologies such as 802.11a and 802.11g and other enhancements to Wi-Fi. In fact, the Wi-Fi Alliance® has implemented interoperability testing programs for 802.11a and 802.11g.

In addition, the Wi-Fi Alliance® WISPr subcommittee (Wireless Internet Service ProvideR) is involved in promoting the acceptance of wireless technology for ISPs to provide wireless Internet services to and throughout businesses and homes. The WISPr group is also involved in developing the growing public access and "HotSpot" markets, working with various organizations and companies to develop common billing and authorization systems so that mobile professionals can easily use their personal wireless ISP accounts at public wireless HotSpots worldwide.
Can I mix and match Wi-Fi components, or is it better to stay with a single manufacturer?
Yes; if the component is Wi-Fi CERTIFIED™ for the same frequency band (e.g. 2.4GHz) and features (e.g. WPA2), you can mix and match wireless LAN products produced by different manufacturers. The Wi-Fi Alliance tests all products independently before they receive Wi-Fi Certification to ensure they are interoperable with all other Wi-Fi CERTIFIED™ products of the same frequency band and features, regardless of manufacturer.

While a Wi-Fi CERTIFIED™ 802.11b (2.4 GHz) product will not interoperate with a Wi-Fi CERTIFIED™ 802.11a (5 GHz) product, a Wi-Fi CERTIFIED™ dual-band product will interoperate with all Wi-Fi CERTIFIED™ products.
How do I use my Wi-Fi laptop when I am traveling?
Just find a Wi-Fi network to which you can connect. These networks are becoming common in cities and towns worldwide - Internet cafes and coffee shops are popping up everywhere! - as well as in public areas like airports, hotels and convention centers or anywhere people gather. Some wireless HotSpot networks require you to manually configure your access connection; others work with your Wi-Fi radio to automatically log on. In addition, many large businesses and universities are providing wireless access to visitors and guests at their locations. For more info, check out Connecting when you are on the move.
What is the difference between a wireless gateway and a wireless access point?
Sometimes there is no difference; sometimes there is a big difference. There is no official definition of what a gateway is. Many manufacturers call their wired broadband modem/router connections gateways. However, in general, a wireless gateway is an access point with NAT routing and DHCP server. An access point is a wireless gateway without NAT routing and DHCP server. An access point essentially functions as an extension from an existing wired network to a community of users with wireless laptops and desktop computers.

Most homes and small offices use wireless gateways because they need the NAT routing and DHCP server that enables them to share a single Internet connection among all the computers in the home or office. Most enterprises and large businesses use access points, not gateways, because their wired network (their "backbone") already has NAT and DHCP server supplied by an industrial strength router or hub.

Many access points also have extra network management and advanced user functions and security capabilities built into them. Gateways may also offer specialized security functions like firewalls.

In general, access points and gateways do the same thing: they function as base stations connecting various wireless laptops and desktop computers, ensuring that wireless data gets shared and transmitted among them as needed.
Why do I need to know what NAT and DHCP are?
NAT stands for Network Address Translation and enables your Wi-Fi gateway to share a single Internet connection among all the computers in your home or business. DHCP (Dynamic Host Configuration Protocol) is what enables your network to use TCP/IP to connect the different components. There are various networking protocols. See Windows Networking Tips and Techniques.

Most Wi-Fi gateways for homes and small businesses provide both NAT and DHCP. In general, if you are setting up a stand-alone wireless network, you want NAT and DHCP. If you are adding a wireless gateway to an existing wired network, you probably want to turn off the NAT and DHCP functions built into your wireless gateway and have it function as a wireless access point.
How do I hook up a network using computers with different operating systems?
Most Wi-Fi networks will work with a wide range of Windows operating systems including Windows 95, Windows 98, Windows Me, Windows NT, Windows 2000, Windows XP and Windows CE. Some Wi-Fi systems will also work with Apple Macintosh, Linux, and other operating systems. Check the data sheets and manufacturer specifications. However, once you have your Wi-Fi CERTIFIED™ network up and running, it should be able to talk to and exchange files with other Wi-Fi networks.
How do I add Wi-Fi to my desktop computer?
You can use either an external adapter like a USB Wi-Fi adapter or an internal Wi-Fi card. An external USB radio plugs into your desktop computer's USB jack. To use an internal solution, you need to open up your desktop computer and insert a Wi-Fi card in either a PCI bus slot or an ISA bus slot. For more information, see Adding Wi-Fi to a Desktop Computer.
Can I use Wi-Fi with my Apple Macintosh?
Yes. You have two options. Most newer Macintosh Power PCs, G3s and G4s have a slot for an Apple AirPort Wi-Fi module. If you didn't order it when you bought your Apple computer, you can still buy the module and put it in yourself - installation is very simple. If you have an older Mac laptop with a PC Card slot, you can choose from among several different manufacturers who make Apple-compliant PC Card radios. USB adapters for Apple are also available.

Once you have the correct PC Card radio or Apple AirPort installed, you need a gateway or access point to talk to. You can use the "official" Apple AirPort access point, or you can use any other Wi-Fi access point on the market. As long as it is Wi-Fi CERTIFIED™, it will talk to your Apple Wi-Fi radios.

Many access points and gateways now use a web-based setup routine. That means as long as you have an Internet browser on your computer, you can set up the access point.

Once set up and configured, a network consisting of combined Apple and Windows computers and access points will work together. Of course, unless you are running an emulator program, you won't be able to run Windows programs on your Apple computer and vice versa. However, your Wi-Fi network devices will talk to each other and enable you to share an Internet connection and transfer files among the various computers.
How do I make my wireless network secure?
Wireless security is important, and Wi-Fi wireless networks can enable WPA2 , a sophisticated encryption technology that protects data flowing between Wi-Fi radios and access points. Make sure you enable it on your network. Some Wi-Fi CERTIFIED™ access points or gateways also provide access control function to restrict access to your Wi-Fi network. For more details regarding additional security techniques, please refer to Securing the Network and Wi-Fi Security.
What is the range of a wireless network?
Range varies in a Wi-Fi network depending on the type of Wi-Fi radio you have, whether or not you use special antennas, and whether your network is in an open environment or in a building with lots of walls and furniture. The composition of your walls and floors can also have a major impact. Wi-Fi is a very low powered radio signal and does not penetrate metal, water or other dense materials.

The Wi-Fi Alliance® does not measure or compare different products and their range. However, it has found that a Wi-Fi network generally provides a range of about 75 to 150 feet in a typical home or office. In an open environment like an empty warehouse or outdoors, a Wi-Fi network may provide a range of up to 1,000 feet or more. With the right antennas and optimal placement, a range of up to a mile is possible.

With Wi-Fi technology (802.11b or 802.11a), a "gradual degradation" in range occurs. This means that, instead of stopping all together, your data transmission rate just becomes slower as you move farther away from the access point. For example, with Wi-Fi 802.11b technology, within 100 feet of the access point, the Wi-Fi radio in your laptop computer will get about 11 Mbps data rate. As you move farther away, that rate will drop down to 5.5 Mbps, then to 2 Mbps and finally to 1 Mbps. Considering that many DSL and cable Internet connections are less than 1 Mbps, this connection speed is still very good. See What Range Can You Expect from Your Wi-Fi Network.
Will my microwave oven or cordless phone interfere with my Wi-Fi network?
Microwave ovens and many cordless phones operate in the 2.4 GHz spectrum, the same radio spectrum used by 802.11b Wi-Fi wireless networks. That means they can cause interference - but in most instances this will just slow down the Wi-Fi connection; it won't stop transmission or break the connection.

To reduce interference, you can move a 2.4 GHz cordless phone away from your Wi-Fi equipped computer or base station. Interference usually only happens with older microwave ovens. You can also try changing the channel on which your Wi-Fi network operates consult you product manual for more information. In addition, some manufacturers have developed and implemented special technologies that can minimize interference from cordless phones and ovens. Check with the manufacturer for specific instructions for your equipment.
Who is affected by an "evil twin" and how likely is this type of attack?
Users of Wi-Fi in public hotspots should be aware of the threat posed by an "evil twin". An evil twin can capture sensitive data, even through instant messaging. In reality, the likelihood of attack is low but users should be cautious and use some fairly simple security precautions to avoid becoming a victim.

Certification

What is Wi-Fi Certification?

To understand the value of Wi-Fi Certification, you need to know that Wi-Fi the popular name, trademarked by Wi-Fi Alliance, for 802.11-based technologies that have passed Wi-FI certification testing.

Wi-Fi Certification assures tested and proven interoperability among wireless computer equipment; this certification gives consumers and business buyers confidence that wireless LAN products bearing the Wi-Fi logo have passed rigorous interoperability certification requirements. Such Wi-Fi products include PCMCIA Cards for notebooks, PCI Cards for desktops, USB modules (which can be used with notebooks or desktops), and wireless base stations like access points and gateways. Wi-Fi CERTIFIED™ products support a maximum data rate of either 11 Mbps (802.11b) or 54 Mbps (802.11a and 802.11g).

Knowing that any product with the Wi-Fi logo has undergone rigorous testing makes your buying decision much easier.

How does a company get its Wi-Fi products Wi-Fi CERTIFIED™?
A company must be a member of the Wi-Fi Alliance® to have its products reviewed for certification. Click here to learn how to become a Wi-Fi Alliance® member company.

The Wi-Fi Alliance® has instituted a testing program that outlines how member products are tested to certify that they are interoperable with other Wi-Fi CERTIFIED™ products. Products awarded Wi-Fi Certification have undergone strict, rigorous and independent testing by a laboratory in North America, Europe or Asia. When a product successfully passes the test, the manufacturer or vendor is granted the right to use the Wi-Fi CERTIFIED™ logo on that product and its corresponding collateral material.

Wi-Fi Certification costs vary per certification option chosen (available on the Wi-Fi member pages) and are good for the life of the product. Only individual products, not entire product families, receive certification. Products that have updated drivers or firmware with observed compliance issues may be resubmitted to the testing facility at any time; the certification charge will be reduced per the prices available on the Wi-Fi member pages.

Setting a test date depends on your requested test date and the lab's availability and testing usually takes two to four days per product to complete.
How can I ask a certification question?
Questions not answered in the FAQ's about certification process can be sent to certifications@wi-fi.org.
Where can I find common certification information?
Certification options, test location options, test plans and informational updates to the program are all available to the Wi-Fi membership on the Wi-Fi members pages under Member Information.
How do I fill out the on-line application?
Filling in the application correctly and completely helps to ensure quicker responses and scheduling of test dates, so please take care to fill in the correct Product Name, Model Number and your PO number. You will also need to verify the certifications you are applying for, choose a product category for your product (current examples include but are not limited to: Access Point, Internal Card, External Card, USB Client Device, Wireless Print Server, Compact Flash, Ethernet Client Device and Embedded Client). You will be asked for your lab location preference (current labs include but are not limited to: CA, UK, Japan, Taiwan, Florida), if your product is a module, and if your product is previously certified.
How can I make changes to a testing application that has already been submitted?
In order to immediately change a testing application as soon as error is realized, and before the test date has occurred, an applicant must re-submit their application using the on-line tool. If your test date has been set, and you must re-apply due to application error, you will not lose your original test date. The pre-allocated test date will be moved to the new application, and the old application will be cancelled.

It is also possible, for less urgent items, to change information (Product Name / Product Category) after the test date has passed, before the final Certification Approval from the Wi-Fi Board of Directors. In this instance please coordinate with the Wi-Fi Certification Team.
Can my company certify on behalf of another company?
Certification on behalf of another company is permitted, as long as both companies are current members of the Wi-Fi Alliance, via the on-line application tool. So long as the company certified on behalf of has no less than one contact specified of the certifying company, and all other requirements are met, the application will be accepted.

Each company must go through the certification process for every product it wishes to claim certification to. Two companies may not claim certification to the same product from the same test, only the company that the application was submitted by / or on behalf of may claim certification when the certification process is complete.
Can my company obtain a Wi-Fi Certification for a product "similar" to one my company has already certified without having to go through product application and testing again?
If one product can be certified as a module, and embedded in multiple products, the module can be certified, and then products containing this embedded module may claim certification to the entire product with the embedded certified device, given that the module form is completed and accepted.

If there is not a module component certified, then each product must individually certify, per the current policy.
How can I schedule a test date for my company's product?
Once your Application has been automatically received, and the PO has been sent to the lab location you requested, you will be contacted within 3 business days by the requested lab location to schedule the requested test dates.

Dates are issued on a first come, first served basis, and you always have the option of working with your requested lab location to see if more favorable dates are available in any other lab locations.
How can I obtain the hardware and software that makeup a Wi-Fi Testbed?
The test bed equipment listing and contacts on whom to contact to purchase equipment, are listed in the appendix of every test plan.
What is the process for receiving the Wi-Fi Certification and Logo once my product passes Wi-Fi Testing?
Once a product has passed testing, the Wi-Fi Alliance® further reviews the Certification Application in comparison with the test results supplied by the test lab. This review troubleshoots inconsistencies and common application errors, as well as a company's current ability to participate in the Wi-Fi Certification Program. This review period varies from 1 day to a week and a half.

When this review is completed, the Wi-Fi Alliance® sends an "informal notice" to the applying company's contacts. Within a 48 hour time frame, the aforementioned contacts receive via email, a Certification Authorization Letter (CAL), along with further instructions on how to expedite your certification.

When the CAL is signed and returned, and all instructions have been followed, the final step in the process begins; the Board of Directors final approval. This duty is performed by the Board once per week, and requires a 72 hour review time.

Once the Board has approved the certification, the Approval of Product Certification notice is prepared and sent to the applicant contacts via email. The newly approved product will then be immediately uploaded to the web site.
What are the Rules and Guidelines for the proper usage of Wi-Fi Certification Logos?
The Wi-Fi Alliance® Mark Usage Manual and the Wi-Fi Certification Mark License Agreement contain the rules and guidelines for the proper usage of Wi-Fi Certification, and are located for our Wi-Fi members on the members only pages in the Marketing Materials section.
What does the Interoperability Certificate reflect?
The Interoperability Certificate provides detailed product information regarding capabilities and features that have passed the Wi-Fi Alliance's interoperability testing requirements. For a detailed example of the Interoperability Certificate and definitions of current product standards, click here.
How can I tell if a product has been Wi-Fi CERTIFIED?

Look for the Wi-Fi CERTIFIED name and / or logo on the product.  Only products which have passed Wi-Fi Alliance testing can bear the Wi-Fi CERTIFIED name and/or logo.

Multimedia

What's being announced? Why is this important?
We have begun certifying interoperability of a set of features for Wi-Fi networks that improve battery life for mobile audio, video and voice applications. This functionality is very important to the Wi-Fi industry, because Wi-Fi is increasingly prevalent in small form-factor devices such as phones, PDAs, and video games, in which battery conservation is a concern.
How does WMM Power Save work?
WMM Power Save increases the efficiency and flexibility of data transmission. Specifically, the client device can "doze" between packets to save power, while the access point buffers downlink frames. The application chooses the time to wake up and receive data packets to maximize power conservation without sacrificing Quality of Service.
How much battery life improvement does WMM Power Save provide?
Wi-Fi Alliance estimates that WMM Power Save can provide from 15 to 40% improvement in battery life depending on the application characteristics.
What impacts the variance in power savings?
The power conservation achieved depends on the particular application in use, as well as how effectively the application uses WMM Power Save. The Wi-Fi Alliance has produced a white paper entitled WMM Power Save for Mobile and Portable Wi-Fi CERTIFIED™ Devices which offers guidance to application developers. It is available for free download at www.wi-fi.org.
How does a user turn on WMM Power Save?
If implemented correctly, WMM Power Save will activate automatically when a Wi-Fi CERTIFIED™ for WMM Power Save client device is communicating with a Wi-Fi CERTIFIED™ for WMM Power Save access point. There is no action needed from a user.
Is WMM Power Save based upon IEEE 802.11e?
WMM Power Save uses mechanisms from the recently ratified IEEE 802.11e standard.
How does WMM Power Save relate to the WMM program?
WMM Power Save builds on the successful WMM (Wi-Fi Multimedia) program, which certifies a set of features for Wi-Fi networks to improve the user experience for voice, video, and audio applications. WMM Power Save is an optional component of the WMM program that targets power consumption when using those applications.
How does WMM Power Save compare to legacy 802.11 Power Save?
WMM Power Save is a more finely tuned power save mechanism which draws on a variety of tools to manage power consumption. In legacy power save, the driver decided when to transmit data, while in WMM Power Save, the application makes the determination about when to transfer data. This enables customization of the power mechanism to the particular application (e.g., Voice over Wi-Fi, video gaming, etc.). WMM Power Save is backwards-compatible with legacy power save.
Will devices with WMM Power Save work with legacy devices?
Yes. WMM Power Save clients can be used in legacy mode without upgrading WMM Power Save. WMM Power Save Access Points support legacy power save clients simultaneously with WMM Power Save Clients.
Is my current equipment upgradeable?
We expect some manufacturers will offer a software upgrade for legacy products. However, only devices that undergo testing will be Wi-Fi CERTIFIED™ for WMM Power Save interoperability.
How do I know if a product has been Wi-Fi CERTIFIED™ for WMM Power Save?
Look for the Wi-Fi CERTIFIED™ logo or designation on product packaging, or check the interoperability certificate. Users can also find products that have been Wi-Fi CERTIFIED™ for WMM Power Save by using the product search tool at www.wi-fi.org.
What is WMM?
Wi-Fi CERTIFIED™ for WMM (Wi-Fi Multimedia) provides multimedia enhancements for Wi-Fi® networks that improve the user experience for audio, video, and voice applications.
Is WMM compliant with IEEE standards?
The Wi-Fi Alliance defined WMM as a profile of the upcoming IEEE 802.11e Quality of Service (QoS) extensions for 802.11 networks and started a certification program for WMM to satisfy the most urgent needs of the industry for a QoS solution for Wi-Fi networks. WMMprovides prioritized media access and is based on the Enhanced Distributed Channel Access (EDCA) method.
When did the Wi-Fi Alliance begin performing interoperability certification testing on WMM?
The first products Wi-Fi CERTIFIED™ for WMM were announced in September, 2004.
Is WMM compatible with other Wi-Fi CERTIFIED™ products?
Yes. Devices that are Wi-Fi CERTIFIED™ for WMM also must pass baseline Wi-Fi certification and will interoperate with legacy devices.
Can current Wi-Fi CERTIFIED™ products be upgraded to WMM?
We expect that some manufacturers will have software upgrades for legacy products. Only devices that undergo WMM testing will be Wi-Fi CERTIFIED™ for WMM interoperability.
Is it mandatory that all Wi-Fi CERTIFIED™ products include WMM capabilities?
No. WMM certification is optional, as not all devices need QoS capabilities.
Will more Wi-Fi CE (Consumer Electronic) products be available following the release of WMM? What types of products will support WMM?
Yes. We expect to see more audio, video, and voice CE products incorporating Wi-Fi with WMM. New products will likely include Voice over Internet Protocol (VoIP) phones, televisions, VCRs, PVRs, MP3 players, and game consoles.
How does WMM enable multimedia applications?
Without Quality of Service (QoS), all applications running on different devices have equal
opportunity to transmit data frames. That works well for data traffic from applications such as web browsers, file transfers, or email, but it is inadequate for multimedia applications. Voice over Internet Protocol (VoIP), video streaming, and interactive gaming are highly sensitive to latency increases and throughput reductions, and require QoS. WMM defines four access categories (voice, video, best effort, and background) that are used to prioritize traffic to provide enhanced multimedia support.
How does WMM prioritize traffic?
WMM shortens the time between transmitting packets for higher priority traffic.
When additional WMM capabilities are added, will they be backward compatible?
Yes. All future WMM capabilities must support WMM baseline.

Wi-Fi Protected Setup™

Does WPA2 have session keys?
WPA2 creates fresh session keys on every association. The benefit is that the encryption keys used for each client on the network are unique and specific to that client. Ultimately, every packet sent over the air is encrypted with a unique key. The ability to avoid key reuse and provide unique, fresh encryption keys is a basic tenet of good security practice and is why WPA2 offers such good security.

Convergence (Wi-Fi/Mobile)

What is the Converged Wireless Group RF Profile Test?
The Converged Wireless Group RF Profile Test is a test plan that was jointly developed by CTIA® and Wi-Fi Alliance® to provide detailed radio frequency performance profile in a mixed-network (Wi-Fi and Cellular) environment. Manufacturers of converged handsets and Wi-Fi networking infrastructure devices (access points) can participate in this test program to provide carriers with independent evaluations of their equipment, and carriers can use the test reports to compare handsets from different manufacturers.
What is the benefit of the Converged Wireless RF Profile Test to carriers?
Previously, carriers had no independent source of data about converged Wi-Fi / mobile devices. This industry-supported program will provide detailed information about the RF performance of the Wi-Fi radio in a converged handset, as well as how the cellular and Wi-Fi radios impact one another. It provides a uniform evaluation approach that enables a standard way to contrast and compare converged devices.
What are the tests included in the Converged Wireless RF Profile?
The comprehensive over-the-air testing program provides detailed measurements on key parameters, described in layperson terms below. The measurements are taken in a 360-degree environment in order to create “real-world” conditions:

• Measurements to provide information about the reach of a Wi-Fi radio signal sent by a converged phone or AP, called transmit power (TRP, or Total Radiated Power)

• Measurements to provide information about how well the Wi-Fi radio can detect an incoming signal in a converged phone or AP, called receive sensitivity (TIS, or Total Isotropic Sensitivity)

In addition, the program includes:

• Measurement of the signals ahead of the Wi-Fi antenna, called conducted power and sensitivity

• Measurement of the reduction in sensitivity (desensitization) of a Wi-Fi receiver caused by the presence of an active cellular transmitter, and to ensure that the performance of the Wi-Fi receiver is within acceptable limits

• Measurements of the desensitization of a cellular receiver caused by the presence of an active Wi-Fi transmitter, and to ensure that the performance of the cellular receiver is within acceptable limits

To complete the testing a device must also be Wi-Fi CERTIFIED™ for core Wi-Fi interoperability and WPA2™ security, and CTIA certified for cellular performance.
What types of devices will be tested for the Converged Wireless RF Profile?
The program includes testing for converged Wi-Fi / mobile handsets, PDAs (Personal Digital Assistants), and Access Points (APs).