Wi-Fi 4 to Wi-Fi 7: 802.11 standards and bands for A+

Try 3 questions on this

Pick an answer to see why each option is right or wrong.

1. An organization is replacing its access points so that wireless clients can move into the 6 GHz band, and it wants each client's channel to be as wide as possible to maximize throughput. Which of the following Wi-Fi generations should the organization select?

   Right. In the game that’s Renown for your Networking building.

   Not that one: C is right. In the game your Networking building would lose a little Renown, and this question would come back later.

   Your answerA.Wi-Fi 6Wi-Fi 6 does reach the 6 GHz band, but its widest channels are 160 MHz. Wi-Fi 7 doubles that to 320 MHz there, so Wi-Fi 6 does not give the widest channel.Your answerB.Wi-Fi 5Picks a dual-band generation without checking which bands it uses; Wi-Fi 5 products operate in 2.4 GHz and 5 GHz only.The answerC.Wi-Fi 7Both Wi-Fi 6 and Wi-Fi 7 can put clients in the 6 GHz band, but the Wi-Fi Alliance states that Wi-Fi 7 adds 320 MHz channels in the 6 GHz band, twice the throughput of Wi-Fi 6, whose widest channels are 160 MHz. The widest channel therefore needs Wi-Fi 7.Your answerD.Wi-Fi 4Wi-Fi 4 is an older generation with no 6 GHz operation, so it fails the first requirement before channel width is considered.

   Written from www.wi-fi.org/wi-fi-macphy

2. A user's laptop stutters while streaming 4K video from across an apartment. It connects to a dual-band Wi-Fi 5 router on 2.4 GHz, and a Wi-Fi analyzer shows several neighbors' networks on that band. The laptop supports both bands. Which of the following should the technician move the laptop to?

   Right. In the game that’s Renown for your Networking building.

   Not that one: B is right. In the game your Networking building would lose a little Renown, and this question would come back later.

   Your answerA.Another 2.4 GHz channelA quieter 2.4 GHz channel might help a little, but the whole band is crowded with neighbors' networks, and the Wi-Fi Alliance points high-performance uses such as 4K video to the less crowded 5 GHz band.The answerB.5 GHz bandThe Wi-Fi Alliance says most Wi-Fi 5 products are dual-band and that devices can use "the less crowded 5 GHz band for high performance applications, and the 2.4 GHz band for basic needs such as web surfing." Streaming 4K video is a high-performance use, so the laptop belongs on the router's 5 GHz band.Your answerC.6 GHz bandThe 6 GHz band was introduced with Wi-Fi 6. A Wi-Fi 5 router operates only in the 2.4 GHz and 5 GHz bands, so it cannot offer 6 GHz.Your answerD.Wider 2.4 GHz channelA wider channel in the 2.4 GHz band covers more of a band that is already crowded, so it adds overlap with the neighbors' networks instead of relieving it.

   Written from www.wi-fi.org/wi-fi-macphy

3. An organization in a country that allows the full 1200 MHz of the 6 GHz band is installing fourteen access points close enough that each needs its own non-overlapping channel. It wants every channel as wide as possible. Which of the following channel widths should the technician configure?

   Right. In the game that’s Renown for your Networking building.

   Not that one: C is right. In the game your Networking building would lose a little Renown, and this question would come back later.

   Your answerA.20 MHzThe full band holds sixty 20 MHz channels, so this works, but it is far narrower than necessary. Fourteen 80 MHz channels fit, so the wider width is the better choice.Your answerB.40 MHzTwenty-eight 40 MHz channels fit, enough for fourteen access points, but 80 MHz also gives fourteen separate channels and is twice as wide.The answerC.80 MHzThe Wi-Fi Alliance says Wi-Fi 6E devices in the full 1200 MHz support up to sixty 20 MHz, twenty-eight 40 MHz, fourteen 80 MHz or seven 160 MHz channels.Your answerD.160 MHzOnly seven 160 MHz channels fit in the full 1200 MHz, so half of the fourteen access points would have to share or overlap.

   Show the full explanation and doc quotes

   Fourteen access points each need a separate channel, so 160 MHz runs out at seven; 80 MHz is the widest width that gives all fourteen their own channel.

   Written from www.wi-fi.org/system/files/Wi-Fi_6E_paper_202308_0.pdf