Thursday, December 24, 2015

Ethernet vs. WiFi: Why WiFi is Way Zippier

Speedtest: 94 Mb/s on LAN vs. 314 Mb/s on WiFi
This week, I bought a new TV and hooked it up at home. The key differences between this model and the previous ones are changes to the remote control and the new tvOS App Store. I figured hardwiring it, on my LAN, would be better than WiFi. My thinking was two fold. First, I expected less of a chance of interference on a LAN connection, than wireless, and more importantly, I also thought the LAN connection would be faster.

I was half right. Of course there's less of a chance of RF interference, since wired is better than wireless. But my TV sits less than six inches away from my wireless router. Interference is unlikely.

I was also half wrong. Surprisingly, the new TV's LAN connection is Fast Ethernet, not Gigabit Ethernet. That means the LAN connection to the TV tops out at 100 Mb/s. But the Internet pipe into my living room is several times zippier than Fast Ethernet.

As I said nearly two years ago, Common Sense Can Be Misleading. Even simple theories need to be tested.

12/25/2015 Update from an Apple senior software engineer who contributed to the AppleTV:
The WiFi chipsets implement more of the protocol stack than ethernet chipsets (this isn't unique to the ATV by a long shot). Thus, using WiFi consumes *less* of the main CPU than ethernet, which is counter intuitive in that a wire is more reliable and requires fewer re-transmits. This also means that a wifi only device will idle sleep using less power than a wired device (if power management is of great concern).


FlyingDiver said...

I'd still use the hardwired ethernet, even though it's slower. There's nothing that AppleTV will do that's going to need more than 100Mbps, and the wifi connection is still more susceptible to interference than the ethernet connection. IMHO.

Joe Moreno said...

Those are very good points. Also, the wired connection will be more secure.