Nothing at all. Wi-Fi is actually not an acronym at all. The Wi-Fi Alliance, founded in 1999 to ensure that the Wireless Local Area Network (WLAN) products of different vendors could all work together, simply needed a catchy name to use in their logo and branding, and the one they came up with was Wi-Fi.
Wi-Fi (or WIFI) is the ubiquitous wireless technology allowing computers, smart phones and other devices to connect with each other and to the Internet using radio waves. Interoperability is achieved through compliance with a set of common standards defined by the Institute of Electrical and Electronics Engineers' (IEEE) and known collectively as 802.11.
To provide the highest possible speed wireless connectivity for the widest range of devices, both new and old, Wi-Fi routers and Access Points often transmit and receive radio signals on two separate frequency bands. This capability, which can now be found in most advanced Wi-Fi equipment, is known as dual-band Wi-Fi. The frequencies of these bands are 2.4 and 5 GHz respectively.
If your Wi-Fi access devices and your Wi-Fi access points (or wireless routers) both support dual-band Wi-Fi, but the latter are not equipped with Client Steering technology, you may still be able to improve the performance and reliability of your wireless network by manually selecting the band chosen by each of your access devices. For short distances with relatively few physical obstructions to the signal path (such as walls or ceilings), then the 5GHz band, since it allows for multiple channels to be bonded together, provides a faster connection and thereby offers more bandwidth to the user. The 5GHz band also has the advantage of being less susceptible to interference from non-Wi-Fi devices such as wireless phones, cameras, or microwave ovens – most of which operate across the 2.4GHz band. At longer distances however, especially where the signal must traverse multiple obstructions, and where interference from other devices is at a minimum, then the 2.4GHz band may ultimately offer a more reliable connection. In such cases, the easiest way to force connection at one band or another is to set the access point’s SSIDs to separate identifiers for each band and to then configure each client device’s WLAN preferences to first attempt connection to the preferred band.
With its higher capacity and speed (currently up to 1.75Gbps), 802.11ac is generally recommended for any new deployment where usage is typical of today’s modern multi-media web applications. Even in cases where lower speed is adequate for the time being, the current exploding demand for Wi-Fi bandwidth will almost certainly necessitate an upgrade in the not too distant future.
However, faster Wi-Fi does not always translate to faster performance for users of the network. For example, if the applications and data being accessed are located at the other end of a 500Mbps pipe, then there is no benefit in connecting to that pipe at a rate any faster than 500Mbps. Similarly, if none of the critical applications require more than 2 or 3 Mbps, and the number of concurrent connections is less than 100, again there would be no discernable speed advantage to deploying 802.11ac.
Of course if prices were equivalent, then it would still make sense to deploy equipment compliant with the latest standard, but while 802.11ac devices carry a price premium, there may still be a sound business case to be made for staying with 802.11n.
This depends on the type of access points beings deployed. It is true that the higher the frequency of transmission, the shorter the range. So as more and more access devices are migrated from 2.4GHz to 5GHz, it can be a challenge to keep them all within range of an existing access point location. Luckily, thanks to Smart Antenna technology there is now a better solution to this challenge. By optimizing the radio coverage pattern for each device independently, it is now almost possible to perform a one-for-one replacement of 802.11n APs with smart antennas supporting 802.11ac.
There are multiple ways of improving Wi-Fi range, connectivity and performance, including, but by no means limited to, the installation of a Wi-Fi Booster. But before investing in additional equipment, you should first try our 5 Tips for improving Wi-Fi performance. If none of these recommendations improve your Wi-Fi performance, you are left with two options:
If your Wi-Fi router supports neither 802.11n (2009), nor 802.11ac (2012), then an upgrade is highly recommended as these later standards support data rates that are many times faster than the earlier standards, as well as providing for more secure and reliable connections. If your Wi-Fi router is a more recent model, and performance when connected at close range is acceptable, then yes, a Wi-Fi Booster, sometimes referred to as a Wi-Fi extender or repeater may indeed be the best option. An alternative solution would be to use a powerline adapter.
To maximize throughput and performance for the maximum number of wireless devices, without having to resort to manual band selection (see 802.11ac vs 802.11n? Which Wi-Fi technology should I use?), the more advanced dual-band Wi-Fi routers and Access Points are able to intelligently allocate bands based upon the capabilities of each client and its apparent signal strength. This capability is known as client steering.
Beamforming is a technology common to all 802.11ac access points which focuses radio coverage in the direction of their connected devices. Traditionally, Wi-Fi access points radiate their Wi-Fi signals in just one pre-defined pattern. Typically, this pattern is more or less spherical (or hemispherical for ceiling-mounted units), providing roughly equivalent signal strength in all directions. This works fairly well in situations where the access point can be located in the middle of a large unobstructed area with relatively few sources of competing interference. However, in most real-world situations, such a static beam pattern is inefficient and leads to inconsistent performance and connectivity across the full distribution of access devices. By using a phased array of multiple antennas and varying the signal phase of each so that amplitudes combine at the precise locations of connected devices, signal strength is increased for those devices, with a resulting improvement in connectivity and throughput. This capability is known as beamforming.
A Smart Antenna is a wireless antenna employing a number of advanced features including beamforming, which can support a higher density of access devices while optimizing the overall connectivity and throughput for those devices. It does this by detecting in real time the relative signal strength, direction of arrival, and band utilization capabilities of each access device and interference source, and then adjusting the shape of each radio signal accordingly. This is done through advanced software algorithms which control each of the antennas independently. In this way, a smart antenna such as the ZyXEL WAC 6500, which incorporates an array of 3 x 3 (3 transmit and 3 receive) dual-band antennas, can produce up to 700 different signal patterns, from which, at any given moment, it dynamically selects the best for each access device, while simultaneously minimizing the effect of any detected sources of interference for that device. The result is optimal performance for the largest possible distribution of access devices.
Although today’s wireless access points are reliable, a small proportion of units may fail, and when they do, the resulting gap in Wi-Fi coverage can lead to disruption of service. Access Points equipped with Auto-Healing technology overcome this problem by constantly monitoring their immediate neighbors. Upon detection of an outage, the neighboring access points then increase their transmission power sufficiently to compensate. When used in conjunction with central management and event reporting, this gives the network administrator time to arrange for a replacement unit to be dispatched and installed. Proper planning and power management is required for this process to take place.
Signal attenuation will vary according to the material, thickness and construction of any barrier, as well as the band being used (2.4GHz or 5GHz), but the following provides a rough guide: