Before setting up wireless network, you need to understand 802.11 wireless standard that can be used. 802.11ax (WiFi 6) is latest wireless standard but still lots of people are using 802.11ac (WiFi 5) products. You might also hear about 802.11a, 802.11b, 802.11g or 802.11n wireless communication standard, but they are not that popular anymore. Wireless networks can be built using any of specified standards, but each has its advantages and disadvantages. Let's check out one by one below:
In September of 1999, the IEEE 802 committee extended the 802.11 standard, created 802.11b standard. It became popular due to low setup cost and bandwidth support up to 11Mbps in the 2.4GHz S-Band Industrial, Scientific, and Medical (ISM) frequency range. For your information, the maximum bandwidth supported by original 802.11 standard is only 2Mbps.
Being an unregulated frequency band, 802.11b device can suffer interference from other wireless users, cordless phones, microwave ovens and other devices using the same 2.4 GHz band. However the interference can be avoided by placing 802.11b device a reasonable distance from other devices.
802.11a was created the same time with 802.11b with the ability to support 55Mbps in the 5GHz band. 802.11a is not popular due to the slow availability of the 5 GHz components needed to implement products by vendor, more expensive cost and not compatible with 802.11b. The higher frequency also makes 802.11a signals have more difficulty to penetrate walls and other obstructions.
However the advantage of 802.11a is that it operates at a radio frequency that's less clogged by competing signals from other wireless users, cordless phones and microwave ovens. Its maximum bandwidth is higher as well comparing to 802.11b. 802.11a is usually found on business networks whereas 802.11b better suits the home network.
Due to 802.11b is not compatible with 802.11a and there are needs for higher bandwidth, 802.11g was ratified in June 2003 to provide high data rate and maintain backward compatibility with 802.11b products.
802.11g supports bandwidth up to 55Mbps in the 2.4GHz band. 802.11g is compatible with 802.11b products because they both use the same radio frequency band (2.4GHz) to transmit data over the airwaves, it means 802.11g wireless router will be able to talk to 80.11b wireless adapter. 802.11g also provides better security features, such as WiFi Protected Access (WAP) and WPA2 authentication with pre-shared key or RADIUS server.
Again, 802.11g also suffers from the same interference as 802.11b in the already crowded 2.4 GHz range, but can be avoided by placing 802.11g device a reasonable distance from other devices
802.11n is wireless communication standard that was approved by IEEE in October 2009, and it can provide bandwidth up to 300Mbps, around 6 times faster than 802.11g.
Prior to the release of this final approved 802.11n, several vendors already produced the wireless products based on 802.11n draft standard and they’re called 802.11pre-n or 802.11n(draft) wireless products, and it’s good to know that the 802.11n wireless product is backward compatible with those draft-n products.
Furthermore, 802.11n can operate in 2.4GHz or 5GHz band, and is backward compatible with 802.11a (5GHz band), 802.11b (2.4GHz band) and 802.11g (2.4GHz band) products.
If you want to set up a wireless network, you can use wireless products that support 802.11n standard that supports much higher bandwidth since it's mature technology and the price is reasonable too.
802.11ac (WiFi 5)
802.11ac is latest wireless standard that was developed and approved by IEEE in January 2014. It can provide bandwidth up to 1 Gbps, and so it’s called Gigabits Wifi too.
801.11ac only operate in 5 GHz band (not 2.4 GHz band), but still it is backward compatible with 802.11n, 802.11g, 802.11b and 802.11a wireless standards. This means you can buy 802.11ac device and still it will work just fine with your existing router. 802.11ac is called as Wi-Fi 5 by WiFi Alliance too.
802.11ax (WiFi 6)
802.11ax or WiFi 6 is latest wireless standard which was finalized in late 2019 and it can support bandwidth up to 10Gbps combined bandwidth with much lower latency than WiFi 5.
Unlike its predecessor 802.11ac (WiFi 5) which only support 5GHz band, WiFi 6 supports both 2.4 GHz and 5 GHz frequency bands. It is also backward compatible with all other older wireless standards.
It can provide four times the throughput per user in crowded environments, and also better power efficiency which should give a boost in device battery life. Its MU-MIMO and OFDMA capabilities greatly improve wireless capacity and performance by enabling more simultaneous connections and much thorough use of frequency.
If you have Gigabit broadband connection and do online gaming or video streaming frequently, you can consider the deployment of 802.11ac (WiFi 5) or more expensive 802.11ax (WiFi 6) wireless adapter and router on your wireless network for impressive network performance.
Note: WiFi 6 is supporting 6 GHz band too (WiFi 6E) according to update from WiFi Alliance here in January 2020 in which it will provide more frequency band selections for setting up wireless network, and it will take some time for the manufacturers to come up with 6GHz supported wireless products. In general wireless network operated in 6GHz band will provide faster speed with lower latency compared to the other two frequency bands. The other benefit is that 6GHz band will not suffer from interference coming from other home wireless devices (microwave oven, baby monitors, walkie-talkies, etc.) that operate in the 2.4GHz or 5GHz band.
Note: What is next wireless standard? Well! It's called 802.11be or WiFi 7 and still work in progress by IEEE. From my understanding it will provide bandwidth up to 30Gbps with low latency, and many other new capabilities.
Note: What is the difference between 2.4GHz and 5GHz wireless network? Well! 2.4GHz wireless network tends to have better coverage but lower data rate, whereas 5GHz wireless network gives you much better data rate with less interference but smaller coverage.