Thursday, April 4, 2019

WiFi 6 vs. 5G - Coming Soon to a Computer Near You

The coming next generation of cellphone data services, 5G, has gathered lots of attention.  So much attention that there are already lawsuits over Verizon and AT&T advertising they have 5G even though nobody really does.  I hope it's obvious that 5G means "Fifth Generation", as opposed to the currently widely distributed 4G (fourth...), LTE (long term evolution) and so on.  For reasons I don't really understand, 5G is gathering much more hype - probably because it's coming at the same time as the "Internet of Things", IoT, (as I call it, the Internet of Things That Don't Quite Work Right - IoTTDQWR) and the IoT is gathering lots of suspicion as reporting everything you think do or say to some Them.

Electronic Design magazine's newsletters treat us to an interview with Cees Links of the Netherlands, one of the original inventors of WiFi.  With the title, "Wi-Fi 6 vs. 5G: Why Trying to Pick a Winner is Missing the Point", it's really not about which makes the better network so much as talking about making the networked radio experience better all the way around.

Perhaps you've missed the buzz about WiFi 6 coming, so the Verge has a good introductory article on some of what's different.  Like 5G, it will be "real soon now", probably by the end of this year, because the specification doesn't appear to be released yet.  

This is where I find Cees Links' perspective good to read:
Of course, some of the messaging around 5G is just marketing hype, showcasing the favorable points and ignoring the less favorable ones. The claim is that 5G with 4 Gb/s will be faster than Wi-Fi (.11ac) with 1.3 Gb/s. The immediate counter argument is that Wi-Fi (.11ax) with 9.6 Gb/s will be faster than 5G.

But will these speeds be achieved in real life? We’ve seen this before, these glossy promises of high-speed access being wiped away by the hard truth of “but I still cannot get a decent connection in the basement,” or something similar, because—and here’s the real headline—how good will 9.6 Gb/s Wi-Fi be in the basement, if the connection to the home is 300 Mb/s, or even less? It seems like we’re working on the wrong issues, doesn’t it?
To begin with, let's get something out of the way.  5G isn't going to get all new spectrum and while they do go into chunks of spectrum previously unused by phone data links, 5G also reuses other frequencies the older generations use.  This chart from Keysight Technologies, a long time test equipment maker, is color coded:

The purple numbers are 3GPP or LTE frequencies repurposed for 5G and the teal numbers are new 5G frequencies.  The important points are the spectrum reuse, that many of the 5G frequencies are currently in use, and to point out that those numbers on far right go as high as 40 GHz.  These frequencies don't penetrate either the atmosphere, walls, or leaves on trees, and other bits of the environment very well.  Yes, running more power can help, but they can't run unlimited power due to safety regulations and the extra power just doesn't buy much. 
Better coverage inside the home is one of the key characteristics of the new generation of Wi-Fi, now called Wi-Fi 6 (based on the IEEE 802.11ax standard). The distributed concept behind this new version of the Wi-Fi standard (also called Wi-Fi mesh) helps to distribute internet to every room in the home, with the main router at the front door, and small satellite routers (also known as repeaters) on every floor and in every room. This enables internet service providers to sell and support solid internet connectivity everywhere in the home—all good news!
As a consumer, I think I'm pretty typical in that I don't care what radio protocol I'm using, WiFi 6 or 5G; I just want it to work right.  Anywhere - whether that's here at my desk or if I need to communicate from the side of a road at some point.   The drawback to all this is that I need to go buy new hardware and I think I'm a pretty typical consumer in not wanting to do that.  There are no 5G cellphones yet (and my bet is that it will be years before 5G gets here to the small town).  Likewise, there are no WiFi 6 routers yet - the 802.11ax specification is expected to be implemented by the end of the year.  It seems to me WiFi 6 will be here before 5G, but that would require I buy a router, then repeaters and then things that go on the other end of the WiFi link. 

Cees Links raises some interesting points about the cellphone industry coming from a background of the heavily regulated telephone industry, selling frequency access while the WiFi industry comes from a background of using unlicensed frequencies.  When the cellphone providers think of providing data services like 5G, it's like bringing the phone twisted pair to your house: what you do in the house is up to you.  Likewise, the WiFi provider thinks of selling you a router and then you make everything work.  Nobody has done a good job of integrating the router and the cellphone data stream.  That's probably what consumers want more than disjointed pieces of hardware and data services that just don't seem to work right.


  1. To your last statement about integration, the phones themselves seem to do a pretty good job of seamlessly transitioning from cell to wifi when they detect a usable signal and vice versa. As long as that happens I suspect most consumers don't really care about the network architecture.

    1. Cees Links says that process isn't as seamless as it should be all the time. The problem is the borderline cases where WiFi is weak and it switches improperly. The quote:

      Fortunately, most phones are somewhat smart, and when the Wi-Fi connection isn’t working, the phone automatically switches to the cellular network. But there’s a real problem if you’re “on the edge of Wi-Fi” and Wi-Fi attempts to take back the connection, leaving you in limbo with a nonworking Wi-Fi and a nonworking cellular connection. In those moments, the solution is to turn off Wi-Fi to end the battle and avoid poor response times.

    2. Good point, that happens sometimes especially near my kids' school.

  2. Point well made SiG. We had an old 900 Mhz cordless phone in our shop, in a metal hanger. We could walk all the way out to the edge of the ramp and it would still work. Got dropped one day. In comes the new 2.4 Ghz cordless. Got 10 feet outside the shop and nothing. Sometimes newer, better, faster is not always.

  3. This is OT but have you seen the Reuters article on the final moments of the doomed Ethiopian airlines flight? Apparently a bird strike took out the angle of attack airflow sensor. This caused the MCAS to push the planes nose down. Crucially, the pilots did not reduce power from the full takeoff thrust. When they shut off the system as instructed by Boeing, apparently they could not get power assist to undo the changes set by the software. With full power they were going much faster than usual and this made it impossible to manually change the controls.

    Monumental screwup by Boeing and failure of oversight by FAA


    p.s. do a search for the article. I am not posting a link to reduce chances of getting snagged by your spam software. Email me for the link if you cannot find it.

    1. No, I haven't seen that. I haven't been paying a lot of attention to that story, just allowing myself pick up stuff by osmosis. More like "assmosis" - where you only learn things you hear while sitting around.

  4. The article is scary. I am not normally a scaredy-pants flyer but I would have serious reservations (no pun intended) flying the new Boeing planes. When this first happened Rush commented that insiders told him all this started when Boeing decided to change the engines to more fuel efficient models that were heavier. This threw off the 737's center of gravity. Instead of re-designing the plane Boeing decided to fix the problem with software. Hence MCAS. Also apparently there are systems to help with problems like this that Boeing made optional and expensive so most airlines did not buy them.

    I wasn't there but apparently much too little attention was given to a possible sensor failure. Monumental screwup by the management and the engineers who let this get by.


    1. In the intervening time, I found the article and caught up with that.

      Disclaimer is that actually flying anything is way beyond my area of expertise. I took private pilot ground school - that's the extent of my training. I know what flaps and slats are, what the system is doing, and just that basic understanding.

      I was involved, however, with the weather radar system on the max, which was a replacement of the legacy radar used on the 737 series, with a different radar because of those bigger engines. The bigger engines required longer landing gear and the longer landing gear hit would the waveguide (small, rectangular, hollow pipe for carrying radio signals) between the antenna in the nose and a box in avionics bay. The newer radar puts all the electronics in the nose and connected to the avionics bay by something more like an Ethernet cable, in that it was flexible and could route around the landing gear.

      The bigger engines were for higher efficiency and lower fuel costs (BIG deal to the airlines). Karl Denninger says that the engines also were moved forward and up compared to the previous versions, and that affected both balance (center of gravity) and trim (neutral position in flight) which led to the changes in the MCAS system that's at the center of this.

      I have no idea if Karl is right, but if the engines moved as he said, it would be understandable in terms of them being bigger, high-bypass engines and what else I know. This might be the most poorly conceived patch ever. Supposedly (again, per Karl Denninger), the major customers for the 737 Max project pressured them to not require a completely new certification on the aircraft, which costs them big bucks.

  5. WiFi 6 and 5G may be faster, but the last time I looked, NEITHER one was secure. (WiFi 6 has some of the same problems impacting WiFi for the past 4 years.)

    Because neither group cares about security. But then I'm beginning to think that no one cares about security. (Steve Gibson - who coined the term malware - says if you offer people a candy bar, they will give you the password to their bank account. It is almost that bad.)

    But then I doubt I will ever see 5G where I live. The 4G signal is fairly week, and for a long time, you could predict the intersection at which you would lose 4G on phones/tablets and they would fall back to 3G.