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The 802.11b Standard
Hardware standards in the WiFi area involve how well the product can send and receive wireless signals. The 802.11b standard is designed to provide a series of objectives that a wireless device must comply with.
The standard clarifies two objectives, speed and frequency interference. The 802.11b standard operates at a range of 30 m or100 ft at the frequency speed of 11 Mbit/s. It also uses the CSMA/CA (carrier sense multiple access / collision avoidance) detection method before sending signals out of the transmitter/receiver. It avoids frequency collisions by sensing if there is a signal in the same gigahertz range, which is 2.4 GHz.
802.11b devices tend to suffer frequency interference from other products operating in the same 2.4 GHz range. These include: microwave ovens, Bluetooth devices, and cordless telephones. The standard is a product of the IEEE (Institute of Electrical and Electronics Engineers) an international organization that sets standards for electrical and electronic devices.
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The Wifi Alliance
WiFi Certification belongs to the WiFi alliance. This is a group that owns the Wi-Fi Certified logo, which is permitted to be used only on equipment which has passed the rigorous testing. They provide testing standards not only for radio and data interoperability, but also for security protocols, and they also test for Quality of Service feature sets and power management protocols.
Wi Fi Cerfified products have to show that they can perform well in networks that have other Wi Fi certified products. They have to operate running common applications in situations that mimic those encountered in everyday use.
Source: The WiFi Alliance
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The Wifi Alliance has a practical approach to device certification. There are three principles involved.
1) Interoperability or the ability for one device to interact with another is the primary goal of certification. A rigorous test procedure is used to guarantee that products from different equipment manufacturers can interoperate in a wide variety of settings and configurations.
2) Backward compatibility or new equipment and devices have to work with previous generations of devices that performed the same task. Backward compatibility also has an economic component; it protects legacy investments in Wi Fi products and avoids the sudden shock to consumers that their products won't suddenly work. It enables consumers to gradually upgrade and plan methodically for the new generation of devices.
3) Innovation or allowing new product design and technologies to be introduced into the market place. This is supported through the introduction of new certification programs to match the latest technologies and specifications as they arrive into the marketplace. These certification programs can come in two flavors; they may be mandatory or optional depending on the device, its use, and the frequency or market saturation that will be involved.
Source: The WiFi Alliance
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Cisco Compatible eXtensions Solutions
Another WiFi device testing program comes from Cisco Systems. Their program, known as the Cisco Compatible eXtensions (CCX), involves a set of test programs that certifies the interoperability of client devices with their infrastructure products. The CCX logo is given to client devices that have successfully passed CCX certification.
Cisco has designed their testing program with four versions. Each version builds around feature compliance, which then moves the product into the next testing cycle. The working protocol is that every feature supported in one version also must be supported in each subsequent version. Here are some of the elements from each version set:
Version 1: The ability of a WiFi device to interoperate with an access point supporting multiple Service Set Identifiers (SSIDs) tied to multiple VLANs.
Version 2: Radio frequency (RF) scanning, which takes data from the access point and then is delivered to the CiscoWorks Wireless LAN Solution Engine (WLSE) for analysis.
Version 3: Support for Wi-Fi Multimedia (WMM)
Version 4: Call admission control, such as addressing voice over IP (VoIP) stability, roaming, and other Quality of Service related issues.
For more information related to the testing operations see the Cisco Compatible Extensions Program Brochure
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With the move to mobile devices and their ready acceptance by the consuming public it is important that standards be developed and be maintained by a body that oversees what the devices should do. Manufacturers alone will not make that guarantee other that their device will work only with devices made by the same manufacturer. For the consumer that is not good enough. The Wi-Fi Alliance is one testing body that works at setting standards and testing protocols to guarantee that Wi-Fi devices will work regardless of the manufacturer.
Cisco also has set up its own testing center program. It too has a set of rigorous standards that manufacturers will follow in order to be Cisco Certified.