By Joe Levi | May 31, 2013 11:27 AM
The router at Pocketnow HQ recently broke-down and had to be replaced. The one that was chosen to replace it featured the latest and greatest in wireless technologies, including 802.11ac WiFi. Since many of today’s smartphones and tablets are coming with 802.11ac built-in, what does this “new” technology mean for you, and why should you care about making sure your next device has 802.11ac on its spec sheet?
Wireless networking started to gain popularity in 1997 with 802.11a and 802.11b. It was slow. It was expensive. It wasn’t very widespread. Eventually we saw a speed boost with 802.11g and later 802.11n, which is the reigning standard today. While all this was going on, cellular carriers were marching from GPRS and EDGE up to HSPA+ and LTE. In a strange twist of irony, data speeds on your smartphone these days may be faster than your home Internet connection. That’s not the case at Pocketnow HQ, which is powered by a fiber-optic connection as fat as your arm, but our here in the Utah offices, our choices range from DSL and wireless providers, to cable at the top. (Our offices are 70 miles away from the Google Fiber deployment that was recently announced.)
Using the Pocketnow Utah office as an example, we can get “up to” 20Mbps down and “up to” 5Mbps up. We can pay more to get “up to” higher speeds, but in practice, the speeds haven’t increased with the cost. In real-world testing, we average 5 to 7 Mbps down, and about half that on the upload speeds. Using T-Mobile HSPA+, speeds are almost always at least that fast — sometimes faster. Verizon LTE averages 30Mbps up. AT&T LTE is around 20Mbps. Put another way, as far as speed is concerned, we have a disincentive to turn on WiFi on our smartphones and tablets here in the Utah office.
WiFi has some advantages over cellular data, with battery and local-network performance key among them. If you use quite a bit of data, you’ll probably be better served using WiFi rather than data from your cellular provider, regardless of speed.
Once the service provider is no longer the bottle-neck, the network in your home or office is the next constriction point. Many people think that a 100Mb connection on their internal network is just fine, since they’re only getting half of that (or less) on the Internet connection on the other side. While that’s logical, it’s not the right way to look at things. At the Pocketnow Utah office we have a server running all the time, a VoIP box for our telephone service, a workstation for writing articles and editing videos, and a laptop for when the weather is nice and one of us wants to go outside and still get work done. On top of all those we generally have at least five smartphones connected and we have three tablets that could go on at any time. Even with half those devices connected at the same time, the bandwidth to the Internet is significantly reduced per device. Additionally, the bandwidth on the local side of the network is eaten up as well. That 100Mbit doesn’t seem like that much when it’s being used by 10 devices at the same time.
“But Joe, what about Gigabit?” Yes, 100Mbit isn’t top of the line technology. Wired networks tout 1000Mbit, also known as “Gigabit”, all the time. That’s great — if you’re wired. I have yet to see a smartphone or tablet with a Gigabit Ethernet port built-in, let alone someone who would be willing to tether to a hard-line network connection to it. 802.11n provides essentially 100Mbit over the air, which is a nice, round number.
Now that we’ve covered ISP limitations and LAN considerations, let’s talk about 802.11ac, the latest addition to the WiFi family.
Frequencies in the air are not unlimited. Just like a power-strip or Ethernet switch, there are only so many sockets that you can plug into before you’ve got to add another one to carry the load. 802.11b, g, and n all use 2.4Ghz as their carrying frequency. The later technologies can use 5Mhz (as does 802.11a, which no one uses anymore), but people rarely do. The router in the Pocketnow Utah offices is physically capable of operating on 5Mhz, but the firmware it’s running doesn’t support it. What does all that mean? 2.4Ghz is crowded. Bluetooth operates there, neighboring networks operate there, all the devices connected to those networks operate there. Even amateur radio (HAM) operators have privileges to several channels in the 2.4GHz range. It’s noisy which translates to “slow” in practice. Not only that, as noise increases, usable distance decreases.
802.11ac moves up exclusively to 5GHz where it’s significantly less noisy (it’s not as crowded). Range is improved by 30%+. Speeds on the local network are increased to Ethernet-like speeds when you’re not far away, then drop to speeds that you’re used to at distances that are much further away than you’ve been able to go before.
On paper, 802.11ac is a little more power-hungry than previous WiFi specifications. In practice we have to take into consideration something called “race to sleep”. This is a concept that illustrates that by completing a task faster, you save energy because it goes to sleep faster. In other words, the extra power that’s exerted gets the job done more quickly, saving power while the other is still chugging away. You’re not going to notice the difference in power consumption with 802.11ac over 802.11n in everyday use. Contrast this to LTE which, although faster, seems to go through your battery much, much quicker than other technologies.
If you’re currently living on LTE, 802.11ac may not seem impressive when it comes to speeds, but you’re probably going to love your battery savings by using 801.11ac whenever you can.
If you’re not used to the blazingly fast speeds of LTE, 802.11ac is going to knock your socks off!
Image Credit: (cc) CollegeDegrees360