What are the "BSSID Basic Rates" I see when using "netsh wlan show all" command?

[jegesq]

So in environments where you need lots of APs and/or SSIDs and/or need frequent beaconing, then turning up the beaconing speed can greatly cut down on how much airtime is being sucked up by the game of Marco Polo.

Now I'm thoroughly confused. I understood you to say that when there are lots of SSID's around, whether they are being utilized by client devices or not, they spend a good deal of time looking for beacons and thus this can, quite silently, suck up bandwidth that you didn't even know you were using, thus slowing down your own client's bandwidth (because less of it is available for your intended purposes since it's being used on beaconing). This is why I thought it was better to have short beacon intervals in crowded environments, and longer ones where the environment was less crowded. But then you say that if you have lots of SSID's in an area of your router you should "turn up the beaconing" speed to cut down on how much airtime is spent looking for other beacons (the game of "Marco Polo" as you describe it). But doesn't turning up the speed mean that you're sending out longer beacons more frequently and just consuming even more bandwidth? I will say this, I am confused and while I thought I understood what you were saying, evidently I do not.

 

[htismaqe]

I got a chuckle out of this: "...and frankly if you bring a phone, tablet or laptop over that is old enough that you only have 11g in it, you should be ashamed and I don't want you on my network."

Me too.

You guys are mean.

And quite silly.

 

[azazel1024]

There are two different things.

Beacon interval and beacon speed.

If you turn up the speed, this reduces how much time each beacon takes up, as the beacon is trasmitted in less time.

There is also interval, this is how often it is transmited (default is generally every 100ms, ie 10 times a second).

In crowded environments, you want a higher speed (example, 2Mbps) to shorten how much time each beacon takes up. You may want higher intervals, like every 200ms.

Higher intervals increases how long it takes a client to see a beacon and thus possibly connect to the SSID/basestation. This is exacerbated because clients only spend a certain portion of their time listening for a beacon, so a client might miss 5 beacons before it finally sees one, because it wasn't listening for them (doing other things, like transmitting data). So having longer intervals isn't necessarily a good thing, but it CAN certainly cut down on bandwidth sucked up by lots of SSIDs/APs. The downside is slower connect times and worse roaming performance.

Faster beacon transmision rates has the downside that it has no 11b support and higher enough rates might not have 11a/g support. Also at longer distances, the higher modulation rates mean that the client just might not be able to properly hear the beacon (lower signal to noise means that lower modulation needs to be used to be heard properly).

That said, you are likely safe (agian, so long as you don't care a fig for 11b, and who does), turning beaconing up to 2Mbps, which halved the overhead. I would keep beacon interval to 100ms, unless there is a real good reason to change it.

 

[jegesq]

Ok. Thanks for the explanation. As I mentioned before, I just want to set things so my network isn't so much like public school....you know, having to wait for the slower ones....Oh, that is mean, isn't it?

 

[sfx2000]

The main thing with Basic Rates and 802.11

Any potential client needs to see the AP, whether it is a member or not - if it is a member of the WLAN, the basic rate suggests what the beacon is transmitting at so that the client can make the association, and make decisions on what to do from there.

If the client is not a member of the WLAN, it still needs to be aware, esp. if on the same channel - so it knows when to check for "clear air" to transmit...

So playing around with Basic Rates, and GI intervals - get them wrong, and you'll impact the performance of your WLAN in a major way, as neighbours will interfere more, and you might have issues with older clients trying to attach...

sfx

 

[azazel1024]

That is an excellent point and why if you have interfering networks (or potentially interfering networks) you should leave a much legacy stuff turned on as possible (or on auto at least). If you don't though, fair game (my nearest interfering network, at its strongest is slightly more than 30dB below the signal strength of my own network at that location and typically is more like 40+dB below the signal strength of my network).

It is generally once you get in to SNRI of around 20dB that things start becoming very important in terms of hidden node issues, compatibility, CTS, etc (as it is roughly 20dB from peak to minimum power for OFDM and generally RSSI is measured at peak power. So if you have -50dBm RSSI and a neighboring network has -70dBm, that means your peak power is roughly -50dBm and minimum is going to be around -70dBm on the edges of your transmissions and their's will be -70dBm at the peaks and -90dBm at the edges, which means their peaks can possibly be stepping on the edges of your stuff, making bits of your data unable to be heard).