Ethernet. WiFi. Both?

remiller

macrumors newbie
Original poster
Mar 22, 2019
15
2
USA
Received my new iMac today and have just set it up. Router is Apple AirPort Extreme on the desk next to computer. I don’t know whether WiFi, or a hardwired Ethernet connection between the router and computer would work best. I set up both, thinking the iMac would preferentially use one of these. I was surprised to find in system preferences that both seem to be active. What is best to do then? Is there any harm, or alternatively any advantage, in having both of these active? Thank you.
 

dazlicous

macrumors 6502a
Jun 2, 2011
898
198
Manchester
If you go in Network in settings there is a preferred ordered which wired will be top of the list.
Won’t do any harm thou having both connected
 

Colonel Blimp

macrumors 6502
Dec 1, 2016
262
293
I don’t know whether WiFi, or a hardwired Ethernet connection between the router and computer would work best.… Is there any harm, or alternatively any advantage, in having both of these active?
An advantage to having both active is that if one goes out, the other takes over.

(Given that the router is next to your computer, that’s not likely to happen often, if at all. But as it happens, as of half an hour ago I can’t connect to the WiFi on our cable modem/router, yet it’s still functioning via Ethernet. I’m guessing that cycling the cable modem’s power will correct the fault, but in the meantime I’m still online.)
 

Fishrrman

macrumors P6
Feb 20, 2009
17,393
5,627
As daz mentioned, you can specify which connection gets preference (ethernet or wifi) in the network pref pane.

I suggest you do a test:

Get a utility that measures the speed of your internet connection.
"speedof.me" (typed into a web browser) seems to work pretty well.

Next, TURN OFF your wifi for a moment, so that the computer defaults to the ethernet connection.
Run speedof.me and write down the results.

Now, turn wifi back on. DISCONNECT your ethernet for a moment.
Run speedof.me again, this time over wifi.

Compare the results. Which is faster?
Or... are they "a wash", roughly the same?

If the wifi is faster, I'd set up the Network service order with wifi on top, and ethernet just below it. That way, the Mac will try wifi first, but if your wifi goes wonky, it will drop right down to ethernet and keep going.

This is how I have my Mac Mini setup, because the wifi I have (Linksys Velop) is actually faster than my wired ethernet connection (which I think is still Cat5).
Works fine for me.
 

Weaselboy

Moderator
Staff member
Jan 23, 2005
29,302
8,947
California
Wired ethernet will almost always be faster and more reliable than wifi. I run my MacBook docked and over ethernet with the wifi also on.

Set service order like @dazlicous mentioned with wired on top so when wired is available it will run off that.

Even when on ethernet, you want to have the wifi on and connected so things like location services and handoff/continuity will work.

Screen Shot 2019-04-07 at 7.46.03 AM.png
 

montycat

macrumors 6502
Mar 19, 2007
432
118
Florida
Wired ethernet will almost always be faster and more reliable than wifi. I run my MacBook docked and over ethernet with the wifi also on.

Set service order like @dazlicous mentioned with wired on top so when wired is available it will run off that.

Even when on ethernet, you want to have the wifi on and connected so things like location services and handoff/continuity will work.

View attachment 830788
Great tips everyone! I didn't know I could set the Service Order. I had the wifi turned off and was only using ethernet. I can once again unlock my iMac with my Apple Watch. Thanks
 

Fishrrman

macrumors P6
Feb 20, 2009
17,393
5,627
Weaselboy wrote:
"Wired ethernet will almost always be faster and more reliable than wifi."

OK, just ran two tests a couple of minutes ago. My provider is Comcast cable.

First, via ethernet (my Mini is connected to the Comcast gateway downstairs via a LONG 75' ethernet cable, which may only be cat5):
Speedtest ethernet 2019.4.8.jpg


Next, wifi (using a 2-node Linksys Velop system):
Speedtest velop 2019.4.8.jpg


(You'll note that the source is two different servers. When I tried connecting via ethernet to Optimum Online, I got a slower result)
 

Weaselboy

Moderator
Staff member
Jan 23, 2005
29,302
8,947
California
First, via ethernet (my Mini is connected to the Comcast gateway downstairs via a LONG 75' ethernet cable, which may only be cat5):
Notice I said "almost always" and I believe that to be the case.

In your case, I bet that Comcast gateway (hub) only has a crummy 100Mbps connection.

Look in the hardware tab of that ethernet connection and I suspect you will see that is the case.

Here is mine with a 1000Mbps connection.

Screen Shot 2019-04-08 at 8.32.08 AM.png

Unless OP's AE is very old, it would be a 1000Mbps connection over ethernet.
 

Fishrrman

macrumors P6
Feb 20, 2009
17,393
5,627
Weaselboy wrote:
"In your case, I bet that Comcast gateway (hub) only has a crummy 100Mbps connection.
Look in the hardware tab of that ethernet connection and I suspect you will see that is the case."


OK, I looked, here's a screenshot:
Screen Shot 2019-04-08 at 1.00.49 PM.jpg

2018 Mac Mini, OS 10.14.4.
 

Fishrrman

macrumors P6
Feb 20, 2009
17,393
5,627
Weaselboy wrote:
"Yep... that is your issue. That Comcast hub only supports a 100Mbps connection."

Then.... why do I get speeds of 450mbps+ when connecting via the Velop?

It's plugged into the same Comcast gateway.

The Comcast gateway I have is one of the new "xfi" (I think that's what they call it) units, which is designed to handle their "gigabit" services. Looks like this:
https://www.xfinity.com/support/articles/broadband-gateways-userguides

The specs state:
Model Numbers: TG3482G and CGM4140COM
Gigabit Ethernet Ports: 2
Dual-Band WiFi Option: Yes
Maximum Data Throughput: 1 Gbps
 

adamk77

macrumors 6502a
Jan 6, 2008
510
149
Weaselboy wrote:
"Yep... that is your issue. That Comcast hub only supports a 100Mbps connection."

Then.... why do I get speeds of 450mbps+ when connecting via the Velop?

It's plugged into the same Comcast gateway.

The Comcast gateway I have is one of the new "xfi" (I think that's what they call it) units, which is designed to handle their "gigabit" services. Looks like this:
https://www.xfinity.com/support/articles/broadband-gateways-userguides

The specs state:
Model Numbers: TG3482G and CGM4140COM
Gigabit Ethernet Ports: 2
Dual-Band WiFi Option: Yes
Maximum Data Throughput: 1 Gbps
It's likely your Cat5 cable. Cat5 maxes out at 100 Mbps. You'll need at least a Cat5e.
 

Fishrrman

macrumors P6
Feb 20, 2009
17,393
5,627
adam wrote:
"It's likely your Cat5 cable. Cat5 maxes out at 100 Mbps. You'll need at least a Cat5e."

Yes, that's why I mentioned it in post 7 above.
The backstory:

The ethernet cable was installed back around 2009/2010 or so. Back then I was on ATT DSL which maxed out at about 4mbps if that fast.

My sister (who had never had a computer before) got a Dell "Mini 10" laptop which I put a copy of the Mac OS onto (wasn't really that hard). It was clunky, but it worked (later she got a white Macbook, still using it).

But... I didn't have a wireless router -- just an old Belkin wired router.
So... I just bought a long ethernet cable and routed it from the second floor (where the DSL modem was), over the doors, down the staircase, to the ground floor. She could plug into the ethernet and "be on the net". What works... works. Her friend later gave us an older Airport Extreme, and that worked quite well for a while.

Later, we were able to upgrade to ATT Uverse (tv/phone/net), and the ATT gateway was relocated to the ground floor. So I just used the cat5 ethernet to "send the signal in reverse" back upstairs.

Eventually, I got a Linksys Velop. It worked well enough, but with Uverse we were still only getting 8.4mbps at best.

Frontier took over here from ATT, and their prices skyrocketed, so I finally moved over to Comcast cable. The install guy ran a test with his equipment and found the cable line good for around 500mbps (even though I was only paying for around 170-200).

He said the speeds he got were only available using the test equipment he had, not for regular subscribers. So I was surprised when I was able to show 450+mbps using the "SpeedTest" app (free download from the App Store).

I can only get that using a wifi connection, however.
The old cat5 cable can't handle it.
I tried a speedtest upstairs (2012 Mac Mini) while he was here, and was only getting 95mbps or so. He said it was probably due to the old ethernet cabling.

So... there ARE examples where one can get MUCH faster speeds using wifi rather than ethernet! ;)
 
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kohlson

macrumors 68020
Apr 23, 2010
2,026
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The old cat5 cable can't handle it.
You are perhaps only a mouse click away from happiness!

Is there any harm
In situations like this, I've always turned off wi-fi. If nothing else, I see it as more of a security exposure. Wi-fi has a range of a 100+ feet, and you really never know who's on the other end of that, or if you've correctly set up your Mac to lock unwanted intruders out. I'm not saying wi-fi is insecure, but if you don't need it why not eliminate an attack surface? Easy enough to turn on it you need it.
 
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Colonel Blimp

macrumors 6502
Dec 1, 2016
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Weaselboy wrote:
"In your case, I bet that Comcast gateway (hub) only has a crummy 100Mbps connection.
Look in the hardware tab of that ethernet connection and I suspect you will see that is the case."


OK, I looked, here's a screenshot:
View attachment 831068
2018 Mac Mini, OS 10.14.4.
Fishrrman, I notice that your Ethernet interface’s hardware appears to be configured manually to 100baseTX. What happens if you set it to configure automatically?
 

Fishrrman

macrumors P6
Feb 20, 2009
17,393
5,627
Colonel wrote:
"I notice that your Ethernet interface’s hardware appears to be configured manually to 100baseTX. What happens if you set it to configure automatically?"

Heh.
I didn't think that would make a difference.

So... tried this:
- changed from "configure manually" to automatic
- disabled wifi (so only ethernet is active)
- ran SpeedTest again
- got 478mbps download and 12mbps upload.

Amazin' !

I'll have to check that long ethernet cable again. It just might be cat5e after all.
 
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