有关 Wi-Fi 6E 的提示（视频）

Hello everyone, so I'm Wes Purvis and I'm going to talk about 6 GHz again because I did it last year too. So last year, this is pretty much what I said, we think that there's going to be some friction with adoption of 6 GHz because of WPA3 and I think that has largely turned out to be the case. But generally this guidance, which was I would say early guidance for us, still continues.

But we've had a full year under our belt with now large scale 6 GHz deployments and now we have basically completed the client ecosystem where every major operating system has released a client device, so we kind of understand, I guess, client behavior now and that plays into design a little bit as well. So what have we learned? First of all, your SSID strategy comes out to be important of how you adopt 6 GHz. So what do you do, do you do separate SSIDs, a 6 GHz only SSID, do you do a 5 plus 6, do you do, you know, have a separate 2.4 only, do a 5 plus, like there's so many options and it really comes down to what works for you.

Now, some industries have constraints, like in higher ed you have edgerome, which cannot be different in any way. And so, you know, I think in higher ed what we've seen most people are just, you know, turning on 6 GHz on their existing edgerome and at least with Mist, largely I think it's working pretty well. I think one recommendation that I'll make is just from a device standpoint discovering 6 GHz, we see that if you have multi-band SSIDs, that generally works better than having 6 GHz only SSIDs.

If you have a 6 GHz only SSID, at bare minimum, make sure that 5 GHz or another band is also enabled on the AP, so that the client can discover that 6 GHz SSID using an out-of-band discovery mechanism. One thing I'll point out is we've been using this transition mode, especially with WPA3 Enterprise, which I think as JJ mentioned is, under the covers it's actually very similar, but at least with Mist you can have a single WLAN across all three, you know, all three bands with transition mode, and we do some things behind the scenes to only do transition in the, you know, 245 and 6 GHz, you do full WPA3. But when you're thinking about your 6 GHz, you know, adopting 6 GHz, you first have to think about WPA3 and OWE, and it really, there's some nuance to the different security types.

So WPA3 Enterprise, very easy to adopt. If you're not doing it already, turn it on. You're very likely, you'll encounter no issues with turning on WPA3 Enterprise, especially if you do transition mode.

WPA3 Personal is like low-ish risk. We have seen some interop issues, especially with transition mode, so, you know, I know transition mode gets a little bit of grief, as it should in personal, but some clients, especially like older Android clients and like the original Microsoft Surface, really just don't like WPA3 transition at all. So this may be where you think about, okay, do I do a separate, you know, 245 SSID for my older devices that don't have any WPA3 support, and then just do a pure WPA3 in like 5 plus 6, but this is where it kind of comes down to you and your organization's needs.

Also note that the multi-pre-shared key, which I think has become useful in many deployments, is limited in 6GIG. You're generally limited to a MAC-based or other restrictions that are imposed. From a guest access standpoint or open access, OWE is the least mature of, you know, the three here, but now we finally have kind of broad device support with iOS 16 and the latest Mac OS, there is OWE support.

Just realistically, you're probably going to need to turn on transition mode because of the lack of device support. But the point of this slide is, if you haven't turned on WPA3, if you haven't played around with WPA3, do it now. Do it in a safe area of your network, and just get comfortable with it, and then when you're ready, you can adopt 6GIG.

So you don't do the two changes at the same time, you kind of separate the changes. Just speaking specifically on WPA3 Enterprise, the reason I say it's safe is because it is actually very similar. So this is comparing a WPA3 Enterprise to WPA3 Enterprise transition SSID.

There's basically, you have a different, you know, one AKM is removed, and management frame is changed from required to capable, right? That's pretty much your differences there. And so this turns out to be a very safe change to make, and I would say the majority of our customers that have enabled 6GIG have done it with WPA3 Enterprise because it's so easy to do. A note on if you need a provision in devices using device management, there's the device, the MDMs basically are not very smart with WPA3, so you can actually configure WPA2 in your profile, and your clients will connect to WPA3 Enterprise using that.

They don't generally know any better. So, let's talk about roaming a little bit. That's the other, you know, the other thing that comes up is, will my devices actually discover 6GHz? So now that we finally have a full device ecosystem, we did some testing with Android, iOS, macOS, as well as a couple different Windows clients.

And this is our Juniper Sunnyvale office in Sunnyvale. We've done testing at a bunch of different customer locations, but this is just something I can share, and it was a good data set. So basically, these APs, 26 APs on this floor, all broadcasting a 5 plus 6 SSID.

From a transfer power perspective, 5GIG was a little bit lower than 6GIG, right? 6GIG was about one to three dB higher in general. So here is all six of those clients that I showed on that cart, a roaming view over 150 seconds here. Some, you know, some interesting things to point out, right? In some areas, the clients, like, they roam at the same time.

But if you look, there's roaming that's happening, you know, all through here. And here's just a different representation. So you have a Windows client in here, a MacBook, and another MacBook all roaming at slightly different times, right? They're all in this cart.

But I thought this was just a cool view to show that clients actually do roam in 6GIG. So, just some questions. Do clients probe in 6GIG? Yes, they do.

From a 6GIG roaming perspective, this client was actually probing on a couple of different SSI... Sorry, a couple of different channels. So if you look in here, there's channel 133, channel 197, and then it actually connected, roamed on channel 21 in 6GIG. So it was like, look, you know, it had previously done out-of-band discovery using the RNR, and then it pretty much did like a ping, you know, using the probe.

It was like, okay, what is the actual signal strength that I hear you at now without needing to do continuous scanning? So I think there's really optimized off-channel scanning with 6GIG to the point where devices generally if they don't see the RNR in 5GIG or in 2.4, they're not even going to scan 6GIG. So that RNR becomes really, really important. You'll also see 11K in 6GIG.

So here is, you know, just an 11K, and how you know the band is when you look at the operating class, which is all defined in the spec. So let's talk about band preference. These days, most all client devices out there have a throughput metric that they calculate when they roam, and that takes into a bunch of different metrics.

This is the Android version, there's iOS, there's Windows, but channel width turns out to be really important. So we did some testing with, you know, 80MHz in 5GIG and 40MHz, sorry, 80MHz in 6GIG, 40MHz in 6GIG, and here's just an example, right? So the top, this is the same client and, you know, back to back. So 40MHz in 5GIG, 80MHz in 6GIG, the client roamed from 6 to 6 pretty much continuously.

When we went 40MHz on 5GIG, 40MHz on 6GIG, the client flip-flopped between 5 and 6GIG. And how about if we use non-PSCs? So here is, we just disabled all the PSCs to see what happened, right? So there's no APs on a PSC. In this case, the client still roamed in 6GIG.

It still stayed generally on 6 to 6, it did some 5, but I think this is actually really encouraging, especially for those of you that are in Europe, where you may actually need to use 40MHz channels and may need to use non-PSCs. So guidance generally so far from vendors has been use PSCs, but I think we can actually change that. So, you know, we were waiting for iOS, we were waiting for macOS to kind of understand how they would behave.

So I think probably no PSCs is okay. And here's some resources, and don't let anybody ever tell you there's no interferers in 6GIG because there are. Thank you. Thank you. Thank you. Thank you.