R7800 SmallNetBuilder Review

[sm00thpapa]

Issue here. When set to CH 48 in 160MHz mode all devices can find and connect to the network. When switched to CH 52 half of my 40+ devices can't even find the network. Why can't they see CH 52 or any other DFS channel?


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[sfx2000]

Give those devices a few minutes - in DFS land, they can't actively probe for AP's, so they have to do a passive search...

 

[sm00thpapa]

Give those devices a few minutes - in DFS land, they can't actively probe for AP's, so they have to do a passive search...

I left it on CH 52 for over an hour and even searched for hidden network. Still they won't connect. Once I went back to CH 48 they all connected immediately.

 

[Csection]

I left it on CH 52 for over an hour and even searched for hidden network. Still they won't connect. Once I went back to CH 48 they all connected immediately.

I'm far from an expert, but I have a suggestion.
Try d/l Inssider from metageek and you may be able to tell what's going on around you.
Just a thought!

 

[sm00thpapa]

I'm far from an expert, but I have a suggestion.
Try d/l Inssider from metageek and you may be able to tell what's going on around you.
Just a thought!

I been using inSSIDer since it launched years ago. No one in my area has a 5GHz router. Just some devices don't like DFS channels.

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[bodean]

Found my issue. I was on CH 153 which is not supported by 160MHz. Switched to CH 48 160MHz and all is good. Just wanted to see if in 160MHz mode if 80MHz devices would work.

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So Manual Channel for 5GHz of CH 48, works fine with 160MHz?

 

[sm00thpapa]

So Manual Channel for 5GHz of CH 48, works fine with 160MHz?

Yes for all devices. If I go to a DFS channel half of my devices fall off and can't even see the network. Guess some network cards are picky about 160MHz. I opened a case with Netgear and they are looking into it.


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[sfx2000]

Yes for all devices. If I go to a DFS channel half of my devices fall off and can't even see the network. Guess some network cards are picky about 160MHz. I opened a case with Netgear and they are looking into it.

If one is using true VHT160 (not 80+80), one is bound to run into DFS space, at least in North America... because 52-64 is squarely in that range...

So my best guess is that the UI consider the VHT80 plan, where the "channel" is the 20MHz control channel for A/N/AC compat, running 80MHz free, and the 52-64 is conditional if DFS passes...

 

[pege63]

Thiggins writes:
The default Up to 800 Mbps is the 40 MHz bandwidth mode.
Select Up to 347 Mbps if you want 20 MHz bandwidth and Up to 54 Mbps if you want to turn this beast into an 802.11g router. (N)
The other 5 GHz options are Up to 800 Mbps for 40 MHz channel bandwidth and Up to 347 Mbps for 20 MHz bandwidth (N)

But wath about the 5GHz AC mode, how to choose the 80+80/160MHz? (AC)
I dont have CH 42, 58, 106, 122 on 80MHz, and NO CH 50, 114 on 160MHz in the GUI?

This is showing my CH for 20, 40, 80MHz band width, is your the same?
Is it just me that are stupid but this CH are for the 20MHz band width that are showing.
The only right CH are for the 20MHz, but as you can see its shows the same in 40 and 80MHz?!

As the valid channel numbers for various channel widths are: (Is this right?)

Up to 347 Mbps: 20 MHz (N): 36, 40, 44, 48, 52, 56, 60, 64, 100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140, (144, 149, 153, 161, 165, 169) NOT for EU (this is right CH for 20MHz)

Up to 800 Mbps: 40 MHz (N): 38, 46, 54, 62, 102, 110, 118, 126, 134, (142, 151, 159) NOT for EU

Up to 1733 Mbps: 80 MHz (AC): 42, 58, 106, 122, (138, 155) NOT for EU

This is very confused, am right or wrong?

Why its showing just 20MHz CH in all 3 setting for 347, 800, 1733Mbps?

And where is the setting for 80/160MHz, how do we know its on 80/160MHz?

So the question remain is there something wrong with my Router or is it in the GUI?

 

[pege63]

Is there someone that can or wants to anwser about this isue or are am wrong/right about this confusing problem?

802.11ac channels be 20 MHz, 40 MHz, 80 MHz, and 160 MHz wide.

With 802.11ac comes a new channel naming convention that makes referencing these extra-wide channels easier. Instead of listing all channel numbers, channels are numbered by their channel number center.
This new naming convention for 802.11ac makes older naming conventions incorrect.

Older Software and SOHO Routers
"Why does inSSIDer say channel 42, when my router says channel 36?"

Most small office/home office routers will reference too an "wrong" 802.11ac channel by it's primary 20 MHz channel instead of the "correct" 802.11ac channel number.

While not technically correct, you can use the primary 20 MHz channel number to determine what 40, 80, and 160 MHz channel your router is configured to.

So its the SW with there GUI that showing wrong and are wrong in a wave 2 router as NG R7800.

 

[thiggins]

With 802.11ac comes a new channel naming convention that makes referencing these extra-wide channels easier.

Can you please provide a reference for this statement?

11ac routers in general have not been following the center-channel convention. All continue to show the 20 MHz channel numbers (36,40,44, etc.) when 80 MHz bandwidth is set.

So why would you expect different for 160 MHz?

 

[pege63]

Can you please provide a reference for this statement?

11ac routers in general have not been following the center-channel convention. All continue to show the 20 MHz channel numbers (36,40,44, etc.) when 80 MHz bandwidth is set.

So why would you expect different for 160 MHz?

A, Reference here at metageek and that is how i learn and hear about this and how they teach out here.
B, The "correct" 802.11ac channel number would not confused ppl so much then.
C, Yes in a perfect GUI in a SW would be nice and right way to do it.

 

[pege63]

With 802.11ac comes a new channel naming convention that makes referencing these extra-wide channels easier.
Instead of listing all channel numbers, channels are numbered by their channel number center.
This new naming convention for 802.11ac makes older naming conventions incorrect and showing wrong channels.

So to Show the right NEW convention CH you have to choose the OLD convention CH in the GUI for 40/80/160MHz width like this:

So to show 40MHz CH 38 choose CH 36+40

So to show 80MHz CH 42 choose CH 36+40+44+48

So to show 160MHz CH 50 choose CH 36+40+44+48+52+56+60+64

Choose the "P" one of this CH in the GUI.

Wide 80MHz and 160MHz channels improve throughput but only when full channel bandwidth is free from interfering transmissions.

Thats it i hope!

 

[sfx2000]

Can you please provide a reference for this statement?

There's a wireshark reference here with the VHT side - I'll get to it in a bit - but I see where some folks...

Basically VHT will report the center, not just the primary - there one has to dive into 11a...

For 11a/n purposes - there's always a single 20MHz channel (which some might refer to the control channel)....

 

[thiggins]

There's a wireshark reference here with the VHT side - I'll get to it in a bit - but I see where some folks...

Thanks. What I'm looking for is whether this channel numbering scheme is mandated in 802.11.

 

[pege63]

The 802.11ac come along with new channel naming convention that makes referencing these extra-wide channels (80/160MHz) easier on "Wave 2 routers", thats is a fact. And You self posting this in a article here.

They coul do it like this 5GHz AC 40MHz CH38:

 

[pege63]

like this 5GHz AC 80MHz CH42:

like this 5GHz AC 160MHz CH50:

I would suggest that it looked like this in the GUI, to NOT confuse users.
But thats me on this matter.

 

[sfx2000]

Thanks. What I'm looking for is whether this channel numbering scheme is mandated in 802.11.

Look in the VHT Operations stanza of the beacon frame - it will indicate the center of the VHT channel(s) - this is so the client knows where to center, as the beacon runs in a 20Mhz channel for 11a/11n compatibility - in the example below, the 11a/11n beacon is broadcast on Ch161, and this what's observed in most scanners...

Since this is not a 160 or an 80+80 AP, one only notes the center segment 0

 

[sfx2000]

RevolutionWiFi has a nice writeup about channel planning in 11ac as well...

http://www.revolutionwifi.net/revolutionwifi/2013/03/80211ac-channel-planning.html

 

[pege63]

Yes that is what i mean as they write "This results in channel numbers that may look unfamiliar to most WLAN administrators".

But thats I have been taught, and how they teach them out here at the courses.
I'm a little surprised about that, because I thought you over there was ahead of us in that area on this matter.

But now I have got up my mind about this, so the question is whether manufacturers will absorb this information and apply it in their routers?

I can also refer to this 2 page here and here, about my thoughts.