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    RJ11 to RJ45

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    • P
      pfBug
      last edited by

      I've done minimal research on the topic, but here's what (I think) I understand…

      RJ11 and RJ45 are two different standards (analog and digital), therefore they can't communicate directly. They need a modem to communicate and cannot communicate via passive adapters.

      Now, what I want to do is use a different router than my ISP provided. I don't want to use the new router in AP mode because it locks out features that I specifically bought it for. I think I can set the ISP's Modem/Router to bridge mode and then connect my new router to it, but again, this is based on my minimal understanding at this point.

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      • K
        kejianshi
        last edited by

        Rj11 has up to 6 wires and rj45 has up to 8 for gigabit ethernet…

        Ethernet Cat 5 cables have eight wires (four pairs), but under 10BaseT and 100BaseT standards (10 Mbps and 100 Mbps, respectively) only four (two pairs) of these wires are actually used. One pair is used for transmitting data and the other pair is used for receiving data

        So, you should be able to carry up to 100BaseT Full duplex on a rj11 connector but I'm sure you would probably have to make the wire.

        The only reason I could think to do this is if someone used shielded cat5 cable to wire a house's phone service and stuck rj11 ends on it and you wished to use it for ethernet.

        You can - I did.  But I went ahead and put RJ45 jacks in so I would get the full gigabit.

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        • R
          robi
          last edited by

          If the provider offers internet access on an RJ11 connector that also means it's not Ethernet, it must be something else like DSL/ADSL/SDSL.

          One could pop a DSL PCI card into a pfSense computer and receive the service directly without a modem, I think.

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          • K
            kejianshi
            last edited by

            I'd run a external simple modem with no routing functions myself, in a case like that and connect it to pfsense wan with rj45.  (So do it the easy way)

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            • stephenw10S
              stephenw10 Netgate Administrator
              last edited by

              Yep, RJ11 or RJ45 simply defines the connector.  It tells you little about the signals running across it.
              http://en.m.wikipedia.org/wiki/Registered_jack

              Steve

              Edit: Actually reading that wiki page is enlightening. The RJ number does define the connector type and the signals running over it but they have come to define the connector in common parlence. For example RJ45 is not specifically Ethernet.

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              • C
                charliem
                last edited by

                @pfBug:

                Now, what I want to do is use a different router than my ISP provided. I don't want to use the new router in AP mode because it locks out features that I specifically bought it for. I think I can set the ISP's Modem/Router to bridge mode and then connect my new router to it, but again, this is based on my minimal understanding at this point.

                If you set it to bridge mode, AFAIK it does become a simple modem.  You then just run ethernet CAT 5 from your (now simple) DSL modem to your WAN pfSense port.  It should already have one RJ11 jack for the telco connection and one RJ45 jack for the ethernet connection.

                I'm not sure I see how or what features would be used if you set it to bridge mode.  The modem just disappears and becomes part of the furniture :)

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                • G
                  gbpfsense
                  last edited by gbpfsense

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