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Connect to another pc without internet

Last response: in Networking
August 30, 2012 5:38:53 AM


I have a laptop with an ethernet cable which is connected to desktop computer. I want to access the files on the desktop computer through the ethernet cable but i don't have internet. will this work?

thanks Joe

More about : connect internet

August 30, 2012 5:53:10 AM

Yes. Just patch one to the other and make sure each is configured to use DHCP (auto configuration, which is usually the default).
August 30, 2012 8:18:45 AM

eibgrad said:
Yes. Just patch one to the other and make sure each is configured to use DHCP (auto configuration, which is usually the default).

That wont work without a DHCP server!
You need to connect them with a ethernet cable, and assign them addresses yourself! the IPs will have to be different but the subnet mask must be the same.


You dont need a GW address if there is no internet access.

If the PCs are older and the NICs can't autonegotiate you may need a crossover cable to connect them.
If you dont have any ethernet cables and you have to buy one, your safest option would be a crossover. It will work in either case.
August 30, 2012 12:03:03 PM

^^ This is a common misconception. Did you ever notice on any ipconfig the following two lines, particularly the second?

Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes

That second line is significant, because what it’s saying is this PC will automatically configure itself in the absence of a DHCP server.

Each PC randomly generates an APIPA address (169.254.x.x) and then makes an ARP request to see if by chance the IP has been duplicated. Unlikely, but if it has, it generates a new APIPA IP address and tries again, until eventually every PC is unique. And those are perfectly valid IP addresses. It’s designed for precisely these circumstances, where there is no DHCP server, so communications can still be established. The reason we tend to think these are INVALID is because most of the time we DO expect to find a DHCP server.

As far as crossover cables, we’re long past those days. Yes, there’s always the remote chance this could be a problem, but that would require *both* PCs to be quite old. As long as one side is even a relatively modern PC, auto-sensing MDIX will make sure the connection’s polarity is correct. Even if you have many PCs using a switch, as long as the switch supported auto-sensing MDIX, it would work even if *every* PC didn’t!

So in 99% of the cases, you don’t have to do anything but patch the PCs together. It just works. And which is why I *intentionally* don’t mention it (I used to, but not anymore).
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