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My laptop's RJ45 Ethernet socket has failed. Is it possible to use the RJ11 socket to connect to the network via some kind of adapter? Would Windows be able to use the RJ11 to connect to the internet?

What I have: a (presumably) working RJ11 socket in my laptop. An ethernet cable with RJ45 connectors at each end. A virgin media cable modem that one end of the ethernet cable goes into.

I hope that makes sense! I barely know what I'm talking about here!!

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migrated from Aug 14 '13 at 19:58

This question came from our site for system and network administrators.

And barely know how to read the Help link at the top of the site. – mfinni Aug 14 '13 at 19:57
You can not use an RJ11 connector for ethernet. Search amazon for a usb to ethernet adapter. – spuder Aug 14 '13 at 20:03
Technically you could, you just can't use the one in your laptop for that. – Ignacio Vazquez-Abrams Aug 14 '13 at 21:28
Ever heard of dial-up? – Joel E Salas Aug 14 '13 at 23:41
Does the laptop have a USB 2.0 port? The adaptor is less than $10 and the right way to go. – JoeTaxpayer Aug 15 '13 at 0:31

The required equipment for you to make a network connection using your modem will cost more than a USB NIC, and have worse performance. Don't even try.

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Yeah. Instead, get a USB Ethernet adapter. – David Schwartz Aug 14 '13 at 19:49
I see... I just found this: link Would that be the better solution? – sall Aug 14 '13 at 19:49
Yes, that would be the way to go. – Keltari Aug 14 '13 at 20:01
@sall If your laptop is new enough to have a USB3 port a USB3-gigabit adapter would give significantly better performance. Otherwise yes. – Dan Neely Aug 14 '13 at 21:06
@DanNeely - a laptop that still has an internal dialup modem would be lucky to have USB2 ;) – Mark Henderson Aug 14 '13 at 21:58

The problem is not all related to the connector (RJ11), but the electronic inside, that is connected to the modem for PSTN line. Default (no passive POE for example) 10/100 Ethernet uses only 2 pairs of wires, and requires just four "vias" in the connector.

@Signal15 PSTN modems are still used, some satellite connections use the PSTN line with a modem for the uplink, less and less of course, but is not that "archaic" that no one will have.

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The RJ11 is for dialup connection. It's already have a modem inside. In fact you can connect through it but the speed is not anymore faster than dialup (56/115/231kbps), and the outside equipment is not cheap

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