Although these new wireless LAN standards for 802.11 were announced in 2011, for some reason there is only a slow uptake on 802.11ac and hardly any response to 802.11ad at all. Both standards relate to the speed of data traffic and so have the potential to make significant impact on Wi-Fi networks.
Speed is a compelling argument, and this is the easiest way to market WLAN and its evolution path worldwide. These new standards will deliver gross data rates of 1.2 Gbps (or even higher) which, compared with the 2 Mbps speeds available 12 years ago at the inception of WLAN, represents a huge leap forward.
Let’s take a look at each of these standards one at a time: 802.11ad is taking WLAN to the next vacant frequency band, 60 GHz. This band remains widely unused today, and in certain countries is not available for use either. As such we won’t discuss this standard.
802.11ac on the other hand operates in the existing Wi-Fi bands, but in the 5-GHz range only.
Even though it was introduced in 2011, 802.11ac has not yet been ratified by the Wi-Fi industry’s governing body, the IEEE. This is planned for 2014, but history has shown that this may take longer and it is our assumption that this will be the case. Pre-release products have now become available in the market.
The main attributes of 802.11ac are its speed and the use of 5 GHz, which is becoming the most important band for Wi-Fi in the avoidance of network disruption/interference. However, channel aggregation is essential in order to reach the high throughput rates, which means that fewer channels are available for operating multiple WLAN networks. In order to achieve the highest available bandwidths, all of the 5-GHz channels need to be used.
Another major drawback is the lack of 802.11ac clients on the market. None of the manufacturers of tablets, laptops, PCs or handhelds has adopted 802.11ac as their standard Wi-Fi client. Using this standard would mean ordering a device separately, and this makes it less attractive for mass usage or BYOD (Bring Your Own Device) adoption.
This all may sound rather negative, and people may be forgiven for wondering why we need 802.11ac at all. This may well be the reason for the slow-down of the introduction. Nevertheless we do expect that mobile clients will gain maximum efficiency by operating this standard.
In our opinion this standard is primarily viable for green-field networks operating new clients. If you are in a position to upgrade your network, then our advice is to adopt the same approach as with 802.11n and the introduction of 802.11abg—namely, the parallel operation of two networks to keep the two standards separate. This can be done by using a DUAL radio access point supporting both 802.11n and 802.11ac.
When will 802.11ac be the standard? We are not sure, but ask us again in 2015.
WLAN Consulting is an initiative of LANCOM Systems. LANCOM Systems is a leading German manufacturer of wireless LAN technology based on industry standards.