Two 5Ghz bands - TP Link C5400

[Bugses]

Hi LTT,

I don't know much about networks, so I thought I would ask here. I just bought a TP-Link C5400 and when I set it up, I noticed that it got two 5Ghz bands. Why is that? Should I disable one of them?

[Donut417]

17 hours ago, Bugses said:

Hi LTT,

I don't know much about networks, so I thought I would ask here. I just bought a TP-Link C5400 and when I set it up, I noticed that it got two 5Ghz bands. Why is that? Should I disable one of them?

Each 5Ghz radio can do up to 2167 Mbps and the 2.4 Ghz radio can do up to 1000 Mbps. Many routers have multiple 5 Ghz radios, that how they are able to advertise 5400 and all that. They take the theoretical speeds that each radio can do and add them together. In the case of your router they did a little rounding. In any case if you disable it or not it doesnt matter. 

[Alex Atkin UK]

On 7/16/2019 at 7:08 PM, Bugses said:

Hi LTT,

I don't know much about networks, so I thought I would ask here. I just bought a TP-Link C5400 and when I set it up, I noticed that it got two 5Ghz bands. Why is that? Should I disable one of them?

The reason for this is compatibility.

 

The lower channels are supported by more hardware, but more likely to be used by your neighbors so not the fastest.

 

The second 5Ghz is probably dedicated to the higher channels, which aren't supported on a lot of 5Ghz hardware but also less likely to be used so potentially faster.

 

It also means you can spread your clients across both 5Ghz networks, so you can have a high bandwidth device on one, another high bandwidth on the other, without them slowing each other down (on the WiFi at least, its still subject to your broadband and how much the router itself can handle).

The antennas may also more more optimised to their specific frequency range, which could also have some improvement on range and speed.

[Bugses]

On 7/18/2019 at 5:54 PM, Alex Atkin UK said:

The reason for this is compatibility.

 

The lower channels are supported by more hardware, but more likely to be used by your neighbors so not the fastest.

 

The second 5Ghz is probably dedicated to the higher channels, which aren't supported on a lot of 5Ghz hardware but also less likely to be used so potentially faster.

 

It also means you can spread your clients across both 5Ghz networks, so you can have a high bandwidth device on one, another high bandwidth on the other, without them slowing each other down (on the WiFi at least, its still subject to your broadband and how much the router itself can handle).

The antennas may also more more optimised to their specific frequency range, which could also have some improvement on range and speed.

Should I then refrain from setting the channels manually on the 5Ghz bands?

[Alex Atkin UK]

22 minutes ago, Bugses said:

Should I then refrain from setting the channels manually on the 5Ghz bands?

That tends to be hit and miss, depending on the router.  I'd certainly try it on automatic first and see if it performs okay.

[dalekphalm]

5 hours ago, Bugses said:

Should I then refrain from setting the channels manually on the 5Ghz bands?

I'd let it do automatic channel selection - in theory the router is scanning router channels for interference. Plus there are so many more channels on 5GHz (compared to 2.4) that it's much less of a problem.

[Bugses]

Alright. I've just been experiencing varying 5GHz readings depending on location and if it's the first or second band. One of them is better when upstairs, and the other seems to be better when I'm downstairs.

[dalekphalm]

4 hours ago, Bugses said:

Alright. I've just been experiencing varying 5GHz readings depending on location and if it's the first or second band. One of them is better when upstairs, and the other seems to be better when I'm downstairs.

And for sure both networks are yours?

[Bugses]

5 hours ago, dalekphalm said:

And for sure both networks are yours?

100%. Here are two results, both taken within a minute of each other, both taken on my phone and within 1 meter of the router. The lowest is what is called 5GHz2 band and the highest is 5GHz1.

 

[Alex Atkin UK]

Theoretically the higher frequencies allow a higher transmit power.  I'd also expect even the slight differences in frequency and antenna placement to have some impact on their propagation.  So you'd expect them to have different characteristics, that is kinda the point of having two networks like that.