brent saner on 1 Jul 2017 12:20:18 -0700


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Re: [PLUG] Guest Wi-Fi


the notion that they won't affect each other if they're on different channels is only partly true. specifically, it's mostly false but can be true under certain circumstances. this is due to channel bleed and signal congestion.

as an explanation, see this model[0]. disregard 12, 13, and 14- those are prohibited under FCC regulations. this represents "channel bleed". have you ever been trying to find a station while listening to the radio, and you get to a certain frequency (let's say, for example purposes, 95.3FM) and you hear two stations at once? then you tune to 95.1FM and hear only one of those stations in crystal clarity, and then tune to 95.5FM and hear the other station in crystal clarity? same exact thing happens on wi-fi, just on a different frequency band. channels 1, 6, and 11 are marked in blue because they're the only unique channels you can implement in a given signalspace if you want to avoid channel bleed. however, that brings me to...

signal congestion. everyone and their mother has some sort of 2.4GHz antenna broadcasting these days. now, because 1, 6, and 11 are the most ideal channels in mixed signalspace, that means that by *factory default* most devices use one of only these three channels (USUALLY ch. 6). the vast majority of consumers don't change their defaults. going back to FM radio above, this is how pirate radio station hijackings would work (does anyone remember those?) - they hop on the same exact frequency another station is broadcasting on, and the stronger signal wins (usually what decides the stronger signal is a balance between 1. distance from a. the broadcast's point of origin and b. the receiving antenna, and 2. the power of the broadcasted signal).

the FCC places restrictions/regulations on signal power for wi-fi.


[0] http://media.boundless.aerohive.com/images/1808964999_figure_1_w640.png

sent from my toaster.

On Jul 1, 2017 14:44, "Chad Waters" <chad@chadwaters.com> wrote:
Yes. Different channels won't interfere with each other. You do need to consider any nieghbors' APs within range though.

I haven't looked at consumer APs in a while: look for a model that supports multiple SSIDs and VLANs and you can do it all with 1 unit.

On Jul 1, 2017 2:01 PM, "Casey Bralla" <MailList@nerdworld.org> wrote:
On Saturday, July 1, 2017 1:33:56 PM EDT JP Vossen wrote:
> Following up on the "Router Recommendations" email, any thoughts on how
> to do "guest" Wi-Fi at home?
>
> One idea is to move the WRT54GL to a guest segment and just get a new
> device for the Wi-Fi (with LAN rules) segment.  But that means that
> guest Wi-Fi is really old, which is not a show-stopper, but...  And I
> can see the 2 units interfering with each other, maybe?
>
> Thoughts?


I've often thought of doing this also.   I think that as long as you don't use
the same (or adjacent) channels on each device, you can have any number of
physical WAPs operating independently.   Just to be safe, I would place them
as far apart as is practical, but I don't think they will hurt each other.


--

Casey Bralla
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___________________________________________________________________________
Philadelphia Linux Users Group         --        http://www.phillylinux.org
Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
General Discussion  --   http://lists.phillylinux.org/mailman/listinfo/plug

___________________________________________________________________________
Philadelphia Linux Users Group         --        http://www.phillylinux.org
Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
General Discussion  --   http://lists.phillylinux.org/mailman/listinfo/plug