Netgate Discussion Forum
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Search
    • Register
    • Login

    Are there different types of RJ45 Connectors for different grades of LAN cables?

    Scheduled Pinned Locked Moved General pfSense Questions
    6 Posts 3 Posters 694 Views
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • T
      Teo En Ming
      last edited by

      Much like there are different types of USB connectors for different USB speeds, for example, Type A, Type B, USB connector for USB 3.0 and Type C for USB 3.1???

      1 Reply Last reply Reply Quote 0
      • JKnottJ
        JKnott
        last edited by

        Yes, there are different connectors for CAT5 & CAT6.  You should use the appropriate type.  Also, there are male connectors for solid or stranded cables, including some that can work with both.  However, putting plugs on solid cable is a bad idea.  There are also 2 wiring schemes, T568A & T568B.  T568A is normally used, but you can use either, provided you do so consistently.  If you mix them on one cable, you'll wind up with a crossover cable.

        PfSense running on Qotom mini PC
        i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
        UniFi AC-Lite access point

        I haven't lost my mind. It's around here...somewhere...

        1 Reply Last reply Reply Quote 0
        • jahonixJ
          jahonix
          last edited by

          @JKnott:

          Yes, there are different connectors for CAT5 & CAT6.

          Even different ones for CAT6 and CAT6a. Remember there's no standard for CAT7 connectors yet.

          @JKnott:

          T568A is normally used, but …

          ..if you're in Europe then the most used config is 568B. Most patch cables are wired that way too.

          1 Reply Last reply Reply Quote 0
          • JKnottJ
            JKnott
            last edited by

            ..if you're in Europe then the most used config is 568B. Most patch cables are wired that way too.

            Actually, T568A is the preferred scheme.  From "Ethernet The Definitive Guide" 2nd ed., pg. 256:

            The term wiring sequence refers to the order in which the wires are terminated on a
            connector. There are two wiring sequence options provided in the ANSI/TIA-568
            standards. The preferred wiring sequence according to the standards is called T568A,
            and the optional wiring sequence is called T568B.

            http://shop.oreilly.com/product/0636920028987.do

            PfSense running on Qotom mini PC
            i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
            UniFi AC-Lite access point

            I haven't lost my mind. It's around here...somewhere...

            1 Reply Last reply Reply Quote 0
            • jahonixJ
              jahonix
              last edited by

              As long as both ends of a cable are configured the same way it doesn't matter.
              One manufacturer (r+m) made a comparison and found TIA568A to be capable of slightly faster transmission speeds than TIA568B. I cannot find the paper ATM though and can't explain why that should be.

              Just found on de.wikipedia that 568A is supposed to be the preferred standard in Europe and 568B is around in the US for historical reasons … oh well.

              1 Reply Last reply Reply Quote 0
              • JKnottJ
                JKnott
                last edited by

                @jahonix:

                As long as both ends of a cable are configured the same way it doesn't matter.
                One manufacturer (r+m) made a comparison and found TIA568A to be capable of slightly faster transmission speeds than TIA568B. I cannot find the paper ATM though and can't explain why that should be.

                Just found on de.wikipedia that 568A is supposed to be the preferred standard in Europe and 568B is around in the US for historical reasons … oh well.

                The only difference between pairs is the twist rate.  Each pair has a different twist rate, to minimize cross talk.  However, with a 10 or 100 Mb cable,the same 2 pairs are used and only the signal direction reversed between A & B.  With Gigabit, all 4 pairs are used.  568B goes back to what eventually became 10baseT, StarLAN.  StarLAN was designed to share an existing 3 pair CAT3 cable with a telephone.  The phone would be on the first pair (blue/white), with the 2nd (orange/white) and 3rd (green/white) used for the LAN.  It also used a 6 position connector, as was common for phones.  This also means that Ethernet was designed to share a cable with phones, but that's not recommended practice now.

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

                PfSense running on Qotom mini PC
                i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                UniFi AC-Lite access point

                I haven't lost my mind. It's around here...somewhere...

                1 Reply Last reply Reply Quote 0
                • First post
                  Last post
                Copyright 2025 Rubicon Communications LLC (Netgate). All rights reserved.