Can you connect 2 PCs together with an ethernet cable?

TrainFan475 · August 19, 2019

I know you probably can, but I want to double check. If both computers support gigabit ethernet, would you be able to transfer files between them at gigabit speeds (assuming the rest of your rig can keep up)?

phoenixflower · August 19, 2019

3 hours ago, TrainFan2019 said:

I know you probably can, but I want to double check. If both computers support gigabit ethernet, would you be able to transfer files between them at gigabit speeds (assuming the rest of your rig can keep up)?

You can directly connect to computer directly using a peer to peer network. The would require you to go to Control Panel -> Network and Internet -> Network and Sharing Center -> Change adapter settings (on the left hand side of the window). right click on your adapter -> Internet Protocol Version 4 (TcP/IPV4) -> and then choose the same subnet mask for both I recommend 255.255.255.0 and choose two IP addresses in the same subnet mask that do not interfere with your WAN if one of them has internet access. So if your internet capable computer is on 192.168.1.1 choose any address segment that does not look like 192.168.1.x.

Windows7ge · August 19, 2019

Yes you can. Connecting them is the easy part. Setting up permissions to let you move files can be a pain.

28 minutes ago, phoenixflower said:

You can directly connect to computer directly using a peer to peer network. The would require you to go to Control Panel -> Network and Internet -> Network and Sharing Center -> Change adapter settings (on the left hand side of the window). right click on your adapter -> Internet Protocol Version 4 (TcP/IPV4) -> and then choose the same subnet mask for both I recommend 255.255.255.0 and choose two IP addresses in the same subnet mask that do not interfere with your WAN if one of them has internet access. So if your internet capable computer is on 192.168.1.1 choose any address segment that does not look like 192.168.1.x.

Once OP connects the two both machines should automatically assign themselves a 169.254.X.X/16 address. Static assignment shouldn't be necessary.

phoenixflower · August 19, 2019

3 hours ago, Windows7ge said:

Once OP connects the two both machines should automatically assign themselves a 169.254.X.X/16 address. Static assignment shouldn't be necessary.

It probably won't work, I've yet to have two computers actually do that correctly in a way that lets them connect to each other. In an ideal world, you would be correct but that part of the standard is super flaky.

Gerowen · August 19, 2019

I've done it in the past and yes you can, with two caveats.

1) You will have to assign a static IP and matching subnet mask to each of the devices since there will not be any DHCP server available to hand out IP addresses.

2) You might have to use a crossover cable. Most of your run of the mill copper ethernet cables are straight through, where the wire order is the same on either end. When connecting two like devices, such as connecting two routers directly to one another, two PCs directly to one another, etc., you are supposed to use a crossover cable. If you remember the OG XBox "link cable" they sold for system link multiplayer, it was just a crossover cable. A lot of newer networking hardware can automatically detect if a cable isn't constructed properly and internally move signals around, so you might get away with using a regular straight through cable, but if you've assigned IPs and subnet masks to the two PCs in question and it still doesn't work, try using a crossover cable. To make a crossover cable all you have to do is flip the green and orange wire pairs, so white/orange becomes white/green on the other end, etc.

https://en.wikipedia.org/wiki/Ethernet_crossover_cable

Windows7ge · August 19, 2019

1 hour ago, phoenixflower said:

It probably won't work, I've yet to have two computers actually do that correctly in a way that lets them connect to each other. In an ideal world, you would be correct but that part of the standard is super flaky.

It's worked alright for me. In fact it's worked when I didn't want it to...if you can imagine that.

I won't fight that assigning static IPs would be the better of the two routes. With static IPs he can address the systems by IP's and map drive letters to share folders for easier access. Also knowing what the client IP is all the time makes things easier.

That and trying to go by hostnames Windows has a tendency to forget how to talk to others and just stops working.

38 minutes ago, Gerowen said:

I've done it in the past and yes you can, with two caveats.

1) You will have to assign a static IP and matching subnet mask to each of the devices since there will not be any DHCP server available to hand out IP addresses.

2) You might have to use a crossover cable. Most of your run of the mill copper ethernet cables are straight through, where the wire order is the same on either end. When connecting two like devices, such as connecting two routers directly to one another, two PCs directly to one another, etc., you are supposed to use a crossover cable. If you remember the OG XBox "link cable" they sold for system link multiplayer, it was just a crossover cable. A lot of newer networking hardware can automatically detect if a cable isn't constructed properly and internally move signals around, so you might get away with using a regular straight through cable, but if you've assigned IPs and subnet masks to the two PCs in question and it still doesn't work, try using a crossover cable. To make a crossover cable all you have to do is flip the green and orange wire pairs, so white/orange becomes white/green on the other end, etc.

https://en.wikipedia.org/wiki/Ethernet_crossover_cable

1) This is debatable. Windows is suppose to give itself an address but it seems this doesn't always work for everyone.

2) You're referring to Auto-MDIX. This is a feature that has been around for about 2 decades now and is standard on most network interfaces (switches/computer motherboards/etc) for him to require a crossover cable today is very unlikely. Even hardware that is old by today's standards support Auto-MDIX.

Gerowen · August 19, 2019

16 minutes ago, Windows7ge said:

2) You're referring to Auto-MDIX. This is a feature that has been around for about 2 decades now and is standard on most network interfaces (switches/computer motherboards/etc) for him to require a crossover cable today is very unlikely. Even hardware that is old by today's standards support Auto-MDIX.

Has it been a thing that long? Holy crap I'm getting old.