Last month, we launched the Pakedge WK-1, a 802.11ac high performance wireless access point (WAP). Like the Pakedge W7x WAP before it, the WK-1 supports devices that operate on both the 2.4 GHz band and the 5.0 GHz bands.
A common question we get from our customers, especially those coming from single band (2.4 GHz) systems, is how do I take advantage of the high performance offered by the WK-1? How do I know if I am utilizing the WK-1 to its fullest capabilities? In this article, we will offer best practices for better performance for your dual band W7x and WK-1 access points.
Before we start, let’s understand the advantages and disadvantages of the 2.4 and 5.0 GHz bands. The 2.4 GHz band has been in use for many years, beginning with the 802.11b standard. As a result, many wireless and mobile devices, including laptop computers, streaming AV devices, control system devices, security cameras, etc. still operate on and support this frequency. The 2.4 GHz signal can penetrate walls and other obstacles and offers a better coverage range than the 5.0 GHz signal. Unfortunately, the 2.4 GHz band is also congested, has three non-overlapping channels and susceptible to degraded performance due to interference. In addition to sharing the band with the many wireless 802.11 based devices, it must also share the band with other non 802.11 based devices, including microwave ranges, cordless telephones, baby monitors, Bluetooth based devices, and Zigbee based devices. In contrast, the newer 5.0 GHz band has 23 non-overlapping channels and enjoys an uncongested RF environment as there are currently few devices that operate in this spectrum (for now). However, the 5.0 GHz signal doesn’t offer the same coverage and range, nor does it penetrate walls and objects as well as the 2.4 GHz signal.
With an understanding of the differences between the 2.4 GHz and 5.0 GHz bands, let’s proceed to the best practices.
Best Practice #1 – Assign different names for your 2.4 GHz and 5.0 GHz SSIDs.
A common practice among network technicians is to set all the WAP SSIDs within a project site to the same name. This enables you to connect to “one” network, and allows you to move from access point to access point throughout the site with one set of login credentials. The client device selects which access point to connect to on the basis of signal strength. As the mobile device roams from one spot to another spot, it detects the new signal and compares it against the signal strength of the existing access point it is connected to. If the signal strength of the new access point is stronger than the other, the device will disconnect from the old one and connect to the new one. In areas where the signal strength between the two access points are nearly the same, the device cannot always decide and may alternately connect to one, and then the other.
This is further complicated in dual band networks when technicians assign the same name to both the 2.4 GHz SSIDs and the 5.0 GHz SSIDs. While this facilitates connecting to “one” network, the user has no control and visibility of which access point the device is connected to, as well as which frequency band it is operating on. For example, the user may want to connect the device to the 5 GHz SSID but is unable to because he sees only one SSID for the entire network. The choice of the which access point, and which frequency band to connect to, is then left to the device. Many of the wireless performance problems can be traced to the device’s improper selection of the frequency band.
In order to regain control and visibility, it is best to assign different names to the 2.4 GHz and 5.0 GHz SSIDs.
Best Practice #2 – Move compatible devices to the 5.0 GHz band.
Imagine driving home from work and getting caught in a traffic jam. No matter how fast your car is, you can only go as fast as the car in front of you, and the car of in front of that car, and so on. Now imagine if you get on the same highway during rush hour, but there is a dedicated traffic lane only for you, and no one else. With no one in your lane, you can go as fast as your car (and your driving abilities) will allow you to go.
In a wireless network, the number one cause of slow performance is interference. Putting a device on the 2.4 GHz band is like driving a car on the highway during rush hour. Putting the same device on the 5.0 GHz band is like driving on your own dedicated traffic lane, free from other traffic.
Whether you are installing a new wireless network or managing an existing one, it is important that you put the devices on the right band. Identify all 5.0 GHz compatible wireless devices, and set them to connect to the WAPs at that band. Although some devices only operate on the 2.4 GHz band, identifying and moving the 5.0 GHz compatible devices will allow the devices to operate more freely.
Best Practice #3 – Design your wireless network around the smaller footprint of 5.0 GHz band.
In order to take advantage of the performance gains offered by the 5.0 GHz band, design the network around its smaller coverage footprint to ensure full wireless coverage throughout the project site. A typical 5.0 GHz optimized network requires 1.5 times more WAPs than a corresponding 2.4 GHz network for the same coverage area. For example, if 10 WAPs are required to cover the site operating at 2.4 GHz, then approximately 15 WAPs are needed for an all 5.0 GHz band network. The actual number may be reduced somewhat through smart design and layout, but the fact remains that more WAPs are needed to support an 5.0 GHz optimized network.
If you design the wireless network around the 2.4 GHz band and its larger coverage footprint, it will leave coverage gaps when you try to operate devices in the 5.0 GHz band. As a result, these devices will never reach their true performance capabilities because they are operating in a suboptimized environment.