Q. What is RJ stands for?
RJ stands for Registered Jacks. These are used in telephone and data jack wiring registered with FCC. RJ-11 is a 6-position, 4-conductor jack used in telephone wiring, and RJ-45 is a 8-position, 8-conductor jack used in 10BaseT and 100BaseT Ethernet wiring.
RJ-11 (Telephone) Plug
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Figure 1 |
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Figure 1 is the wiring scheme for the plug side of an RJ-11 connector. The diagram is shown with the “hook clip” on the underside. The typical RJ-11 connector has six terminals. Usually, only the middle four pins are used. The POTS (Plain Old Telephone Service) residential telephone wiring generally contains two pairs of wires – designed for two separate telephone lines. The center pins (Red and Green) contain the first telephone line. Please note that business (digital) phone systems may be wired differently.
RJ-45 (DATA) Plug Wiring
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Figure 2 |
Figure 2 is the wiring scheme for the plug side of an RJ-45 connector in accordance with T-568B standards. The T-568B standard is the most commonly used. The wiring diagram is shown with the “hook clip” on the underside. The wall jack may be wired in a different sequence because the wires may be crossed inside the jack. When wiring a jack or an RJ-45 plug, remember to keep the “twist” as close as possible to the (jack or plug) receptacle. This will insure compliance with Ethernet wiring standards.
Networking Tools:
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Bulk Ethernet Cable – Category 5e or CAT5e
(You may also use Category 6 or CAT6 cabling which has higher performance specifications and is about 20% more expensive than CAT5.) |
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Bulk RJ45 Crimpable Connectors for CAT-5e or Bulk RJ45 Crimpable Connectors for CAT-6 |
![]() RJ-45 & RJ-11 Crimping too |
CCNP (ENCOR & R), CCNA (R&S), JNCIA-Junos & SEC. Experienced Network & System Engineer.
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