Rj45 introduction
The RJ45 is a type of information socket (ie, communication terminal) connector in the wiring system. The connector is composed of a plug (connector, crystal head) and a socket (module). RJ is the abbreviation of Registered Jack, which means 'registered socket'. In the FCC (Federal Communications Commission Standards and Regulations), RJ is the interface that describes the public telecommunications network. The RJ45 of the computer network is a common name for the standard 8-bit modular interface.
RJ45 type network cable plug, also known as crystal head, is made of eight cores and is widely used in the connection between network equipment (called Category 5 or twisted pair) between LAN equipment and ADSL broadband Internet users. RJ45 performance technical description: contact resistance is 2.5mΩ, insulation resistance is 1000mΩ, and when the electric resistance is DC1000V (AC700V), there is no breakdown and arcing in one minute.
The surface of the card reed is gold-plated or silver-plated, and the wiring diameter is 0.4mm~0.6mm; the plug and socket can be repeatedly inserted and removed no less than 750 times; the 8-wire contact pin is 509 (inch).
Rj11 introduction
The RJ11 interface is similar to the RJ45 interface, but has only 4 pins (8 for the RJ45). In computer systems, RJ11 is mainly used to connect modem modems.
The RJ11 usually refers to a 6-position (6-pin) modular jack or plug. This connector has no international standard and is mentioned in the general cabling standard. Moreover, this name is often used for the 4-pin version of the modular connector, causing confusion.
The difference between RJ45 and RJ11
Different standards, different sizes (RJ11 has 6P6C6P4C4P4C4P2C, where C stands for the number of gold needles in the crystal head; RJ45 has 8P8C).
Due to the different sizes of the two (RJ11 is 4 or 6 pins, RJ45 is 8-pin connector), it is obvious that the RJ45 plug cannot be inserted into the RJ11 jack. The reverse is physically feasible (the RJ11 plug is smaller than the RJ45 jack), which makes people mistakenly think that the two should work together. This is actually not the case. It is highly recommended not to use the RJ11 plug for the RJ45 jack.
Because RJ11 is not internationally standardized, its size, insertion force, insertion angle, etc. are not uniformly in accordance with international standard connector design requirements, so it cannot be guaranteed to be interoperable. They even cause damage to both. Since the RJ11 plug is smaller than the RJ45 jack, the plastic part on both sides of the plug will damage the metal pin of the inserted jack.