Two Ethernet Ports

jackhdev

macrumors 6502
Original poster
Apr 9, 2011
343
0
Bismarck, North Dakota
Would it be possible to "add" an Ethernet port to a Thunderbolt iMac by plugging in a Thunderbolt hub, such as the Cinema Display Apple makes? I'm not saying it would work well, but could this power DHCP, NAT, etc? Thanks for your help.
 

jackhdev

macrumors 6502
Original poster
Apr 9, 2011
343
0
Bismarck, North Dakota
It is 100mbs
Depending on your internet speed it could be way to fast or way to slow.
I barely get 40mbs a second anyway so it is more then enough.
Go to http://www.speedtest.net to check your internet speed.
Post back and I will try to help you :)
That sounds good then :) I'll plug my Internet connection into the USB converter and my LAN connection into the actual Ethernet port. Thanks for your help!
 

wrinkster22

macrumors 68030
Jun 11, 2011
2,623
6
Toronto
That sounds good then :) I'll plug my Internet connection into the USB converter and my LAN connection into the actual Ethernet port. Thanks for your help!
No problem, I am glad I could help you :) If you have any other questions, shoot me a PM
 

DustinT

macrumors 68000
Feb 26, 2011
1,556
0
Would it be possible to "add" an Ethernet port to a Thunderbolt iMac by plugging in a Thunderbolt hub, such as the Cinema Display Apple makes? I'm not saying it would work well, but could this power DHCP, NAT, etc? Thanks for your help.
While it sounds like you've gotten a good solution already, I think it's worth answering your original question too.

Yes, the Ethernet port on the Thunderbolt Display will handle DHCP, Nat, etc, at full speeds for a gigabit Ethernet port.
 

asmiller

macrumors newbie
Nov 5, 2004
19
0
Two Ethernet ports

Would it be possible to "add" an Ethernet port to a Thunderbolt iMac by plugging in a Thunderbolt hub, such as the Cinema Display Apple makes? I'm not saying it would work well, but could this power DHCP, NAT, etc? Thanks for your help.
It is my understanding that the operating system won't handle a connection with two different networks, so there is very little to be gained using two ethernet ports. For example, you can't have one connect to the internet while the other functions as a firewall, DHCP and/or NAT server for machines downstream from it. Linux is much more easily suited for this.

I welcome any corrections, but this is what I understand to be the case.
 

jackrv

macrumors 6502
Jul 14, 2011
300
0
It is my understanding that the operating system won't handle a connection with two different networks, so there is very little to be gained using two ethernet ports. For example, you can't have one connect to the internet while the other functions as a firewall, DHCP and/or NAT server for machines downstream from it. Linux is much more easily suited for this.

I welcome any corrections, but this is what I understand to be the case.
It definately can. I've done it with my iMac. Internet sharing on Macs use this, although most people may use a dedicated router instead. AFAIK, just about every distribution of Unix, Linux, or modern Windows systems can handle multiple networks and route between them, even if the GUI doesn't make it obvious or easy to do.

Aside from the UI and custom apple APIs, Darwin is just the XNU Unix Kernel and a modified NetBSD userland. You could turn a Mac into a router (given enough interfaces installed), Firewall, DHCP server - anything really as long as you have the necessary software/libraries installed, although in these cases Internet Sharing does it all for you through the GUI.
 
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jackhdev

macrumors 6502
Original poster
Apr 9, 2011
343
0
Bismarck, North Dakota
It is my understanding that the operating system won't handle a connection with two different networks, so there is very little to be gained using two ethernet ports. For example, you can't have one connect to the internet while the other functions as a firewall, DHCP and/or NAT server for machines downstream from it. Linux is much more easily suited for this.

I welcome any corrections, but this is what I understand to be the case.
It can definitely do this. I am connected to the Internet via Ethernet and to another network via Wi-fi. Additionally, Mac OS X can handle multiple connections through one interface. My ISP provides me with five IP addresses, so I can connect and host websites through all five IPs through one Ethernet port since my iMac is connected directly to the modem.
 

asmiller

macrumors newbie
Nov 5, 2004
19
0
Two Ethernet ports

It definately can. I've done it with my iMac. Internet sharing on Macs use this, although most people may use a dedicated router instead. AFAIK, just about every distribution of Unix, Linux, or modern Windows systems can handle multiple networks and route between them, even if the GUI doesn't make it obvious or easy to do.

Aside from the UI and custom apple APIs, Darwin is just the XNU Unix Kernel and a modified NetBSD userland. You could turn a Mac into a router (given enough interfaces installed), Firewall, DHCP server - anything really as long as you have the necessary software/libraries installed, although in these cases Internet Sharing does it all for you through the GUI.
It doesn't sound to me like an out of the box iMac or Mini is going to use two ethernet ports to function as a router, which is what I was saying. You're right that the software/libraries are out there, but I was referring to what Apple sells you out of the box. I should have been more careful about how I phrased this. Also, I wasn't referring to creating a wireless router, which in the case of my MacBook Pro, will only use WEP encryption on the wireless side, totally inadequate in this day and age.

I'd still like to hear what the OP wanted to do with a second ethernet connection.
 

belvdr

macrumors 603
Aug 15, 2005
5,657
1,023
No longer logging into MR
It doesn't sound to me like an out of the box iMac or Mini is going to use two ethernet ports to function as a router, which is what I was saying. You're right that the software/libraries are out there, but I was referring to what Apple sells you out of the box.
What Apple sells you (OS X) can do these things out of the box. Internet Sharing is in System Preferences, for example.
 

DustinT

macrumors 68000
Feb 26, 2011
1,556
0
It doesn't sound to me like an out of the box iMac or Mini is going to use two ethernet ports to function as a router, which is what I was saying. You're right that the software/libraries are out there, but I was referring to what Apple sells you out of the box. I should have been more careful about how I phrased this. Also, I wasn't referring to creating a wireless router, which in the case of my MacBook Pro, will only use WEP encryption on the wireless side, totally inadequate in this day and age.

I'd still like to hear what the OP wanted to do with a second ethernet connection.
Yeah, I hate to break it to you, but this is possible out of the box. Windows has this too, since at least 98... I actually did it on 95 but that required some additional software. On the NT\2000 side of things, I believe 2000 had it out of the box. I'm pretty new to the Mac world, so I can't say when it's been in the OS, but I'd guess since at least OS X was released.
 

asmiller

macrumors newbie
Nov 5, 2004
19
0
Yeah, I hate to break it to you, but this is possible out of the box. Windows has this too, since at least 98... I actually did it on 95 but that required some additional software. On the NT\2000 side of things, I believe 2000 had it out of the box. I'm pretty new to the Mac world, so I can't say when it's been in the OS, but I'd guess since at least OS X was released.
Just to be clear, you guys are saying that you can use an OS X machine out of the box to duplicate the functions of a router, connecting to the internet on one ethernet port and routing to an internal network on the second ethernet port (not WIFI). Just to simplify the question, I'm referring to the functions of a consumer grade router that does NAT, DHCP, port forwarding, MAC address filtering, that sort of stuff. I'm not just talking about simple internet sharing, which is more like bridging, of which I was aware. That was not what I was referring to.

I'm running Snow Leopard Server on a Mac Mini hosting a few websites and and just for fun, I tried to find out if I could do all of the above with it using a USB to ethernet adapter and was told there was no way to do it. If that's wrong, I'd be glad to hear it.
 

belvdr

macrumors 603
Aug 15, 2005
5,657
1,023
No longer logging into MR
Just to be clear, you guys are saying that you can use an OS X machine out of the box to duplicate the functions of a router, connecting to the internet on one ethernet port and routing to an internal network on the second ethernet port (not WIFI). Just to simplify the question, I'm referring to the functions of a consumer grade router that does NAT, DHCP, port forwarding, MAC address filtering, that sort of stuff. I'm not just talking about simple internet sharing, which is more like bridging, of which I was aware. That was not what I was referring to.

I'm running Snow Leopard Server on a Mac Mini hosting a few websites and and just for fun, I tried to find out if I could do all of the above with it using a USB to ethernet adapter and was told there was no way to do it. If that's wrong, I'd be glad to hear it.
Never tried it with two ethernet ports on OS X, but have done it on Windows with ease, since Windows NT. I don't see why there would be a difference there.

No, Internet Sharing is not like bridging; it's not even close. Internet Sharing gives you DHCP and NAT. It would be silly to require MAC address filtering if you were using two wired NICs.
 

DustinT

macrumors 68000
Feb 26, 2011
1,556
0
Just to be clear, you guys are saying that you can use an OS X machine out of the box to duplicate the functions of a router, connecting to the internet on one ethernet port and routing to an internal network on the second ethernet port (not WIFI). Just to simplify the question, I'm referring to the functions of a consumer grade router that does NAT, DHCP, port forwarding, MAC address filtering, that sort of stuff. I'm not just talking about simple internet sharing, which is more like bridging, of which I was aware. That was not what I was referring to.

I'm running Snow Leopard Server on a Mac Mini hosting a few websites and and just for fun, I tried to find out if I could do all of the above with it using a USB to ethernet adapter and was told there was no way to do it. If that's wrong, I'd be glad to hear it.
Yup, a Mac and Windows box can replace all the functions of a typical consumer router, heck, they'll do a ton more advanced networking features too.

Sorry man, you heard wrong.
 

asmiller

macrumors newbie
Nov 5, 2004
19
0
Yup, a Mac and Windows box can replace all the functions of a typical consumer router, heck, they'll do a ton more advanced networking features too.

Sorry man, you heard wrong.
Like I said in my original post, I welcome corrections. Thanks.
 

DustinT

macrumors 68000
Feb 26, 2011
1,556
0
Like I said in my original post, I welcome corrections. Thanks.
That's an awesome attitude. Too many people are experts in their own minds. When something doesn't agree with their paradigm they assume it's wrong. Sometimes that's true, but you never know until you've taken a close enough look.

Oh, and it's pretty noteworthy that most consumer routers have a small fraction of the power of your average computer. The first wireless router I owned was a Linksys wrt54g released in December of 2002. It's still regarded as a great router, and I'm sure there's more than a handful of Macrumors members still using one. Wikipedia says its running a single core at 125 mhz, 16 megs of ram and 4 megs of flash storage. Compare that to a first gen iMac from 1998 and you'll see 233-333 mhz processor, 32-384 megs ram and between 4 - 128 gigs of storage. So, even a shallow review of the specs shows more than twice the power in the iMac. Reality would show the iMac has more like an order of magnitude more useable computing ability, not to mention the dedicated graphics card and plethora of i\o devices.

So, the power is there, no doubt. If you want to actually do the routing, all it requires is having more than one NIC in the computer and some basic software. I'm sure you understand, if that old Linksys with 4 megs of flash storage can handle advanced wireless routing functions, any computer from the last 15-20 years could easily do the same.
 

asmiller

macrumors newbie
Nov 5, 2004
19
0
That's an awesome attitude. Too many people are experts in their own minds. When something doesn't agree with their paradigm they assume it's wrong. Sometimes that's true, but you never know until you've taken a close enough look.
I'd rather learn something new than feel right when I'm not. Thanks.
 
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