Exam 220-1001 topic 1 question 102 discussion

The keyword here is ONLY 5GHz; 802.11a is right. 802.11ac supports 2.4 and 5GHz frequencies through 802.11n

802.11ac only supports 5Ghz also, can someone confirm?

Another F*** poor/wrong written question, because both 802.11a and 802.11ac are 5Ghz only... so can't br just one ansewr. But I think it's referring to routers non the standards, infact AC rotuers also support 2,4 ghz ( they are multi standard) but an A rotuer not...

The correct answer here is A. It's....complicated ;-) Copied directly from Comptia-- The main distinction is that 802.11ac works only in the 5 GHz band. The 2.4 GHz band can be used for legacy standards (802.11b/g/n) in mixed mode.

Please read the question properly, is is asking which of following ONLY supports 5 GHz and answer is correct because 802.11 ac supports both 2.5 and 5 GHz Where 802.11 a only supports 5 GHz so A is the correct answer.

This question is evil.

From the CompTIA A+ 220-1001 text book: Use of the legacy standards—802.11a/b/g—is now limited to quite old equipment. You are relatively unlikely to come across networks still supporting them. As 802.11nb and g both worked at 2.4 GHz, 802.11g provided an upgrade path for 802.11b WLANs. Working in the 5 GHz band, 802.11a is incompatible with the other two and was not as widely adopted. The 802.11ac standard continues the development of 802.11n technologies. The main distinction is that 802.11ac works only in the 5 GHz band. The 2.4 GHz band can be used for legacy standards (802.11b/g/n) in mixed mode. The aim for 802.11ac is to get throughput similar to that of Gigabit Ethernet or better. So both 802.11a n 802.11ac seem correct to me, but i'm leaning towards 802.11ac

Another terrible question by CompTIA with more than one answer.

To those that are saying that 802.11ac would also be a correct answer: While I agree that I was taught that 802.11ac can only support 5 Ghz channel, here is an excerpt straight from the CompTIA A+ 220-1001 text book, "requency band (2.4 GHz or 5 GHz)—on an 802.11ac access point, you can use thesame network settings over both bands. Clients will connect to any supportedfrequency. Alternatively, you can configure different network names for eachfrequency. You might want to use one frequency but not the other, depending onthe range of devices you have using the wireless network."

In the all-in-one 1001 & 1002 exam guide it says, " To avoid device density issues in the 2.4GHz band, 802.11ac only uses the 5GHz band.

A - 802.11A Frequency Ranges of the 802.11 network-types: 802.11a: 5GHz band 802.11ac: has channel offerings in both the 2.4GHz and 5.8GHz ISM radio bands 802.11b Operates only in the 2.4GHz frequency band. 802.11g: Operates only in the 2.4GHz frequency band 802.11n: 2.4GHz & 5GHz bands https://www.quora.com/What-is-2-4G-5-8G-802-11ac-dual-band https://www.data-alliance.net/blog/wifi-network-standards-80211ac-compared-to-80211n-80211g-80211a-and-80211b/

My guess is the Answer is 802.11a, because 802.11ac is backwards compatible with 802.11n, and is compatible backwards compatible other "legacy" standards, which would suggest it 'could' support 2.4GH. This would suggest the ONLY wireless standard that supports 5GH is 802.11a. I think it's a pretty stupid question and that's the only reason above I could find whereby the answer is 802.11a

I can't believe I actually paid for a site with lots of mistakes...

the key word is "only"

The answer is 802.11a because it is only capable of 5GHz frequencies. While 802.11ac can go as high as 5.8GHz.

yes, 802.11ac does support 5GHz as well