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A serial connector which looks very much like a standard telephone connector, except it houses eight wires instead of four.

RJ-45s are typically found on computers either integrated into the mother board or on a NIC. Because they are so small they are often used on devices such as terminal servers that have many ports.

Ethernet (10baseT) and Token Ring sometimes use four wires of an RJ-45 plug, 100baseVG uses all eight. 100BaseTX uses the same four wires of the RJ-45 connector as 10baseT but the wire must be category 5 instead of category 3.


(Registered Jack-45) A common data networking interface that employs a cable of twisted wire pairs and an 8-pin modular jack. RJ-45 is used for Ethernet and Type 3 Token Ring networks. See cable categories and RJ-48.

RJ-45 Connectors
Eight-wire RJ-45 connectors are used with Ethernet and Type 3 Token Ring networks.

Variations of RJ-45
These are the variations of RJ-45 pins and wire colors.
References in periodicals archive ?
8220;The addition of these new colors in VERICOM CAT5E and CAT6 RJ-45 Keystone Jacks are the next step in growing the VERICOM CAT5E and CAT6 RJ-45 Keystone Jack offerings for our customers,” said Craig Bates, Marketing Manager for VERICOM Global Solutions.
This black CAT5E VERICOM UTP 24 Port Patch Panel with back to back RJ-45 connectors is made of high quality black metal and includes blanks above each port for ease in labeling.
RJ-45 Connectors with Integrated Magnetics and LED Options Engineered for High-Component-Density Networking and Telecom Applications
A standard RJ-45 Ethernet connector mates the SEM inside the enclosure, simplifying installation, and all operate at +9 VDC to +24 VDC.
It has a built-in network connection with a RJ-45 LAN Connector for remote control and access by a Web browser for diagnostics as well as automatic e-mail of product status and a RS-232C connectivity for remote control.
The unit also integrates multiple Power-Over-Ethernet (POE) RJ-45 injector ports and Power with Serial (PwS) Connectors, so that clean isolated power and signal are carried over a single standard Ethernet or serial cable to connected devices.
Support for Power over Ethernet allows for simplified installation in areas where power isn't available: used in combination with the company's SMCPWR-INJ3 power injector, data and power are easily sent to the access point with a standard RJ-45 Ethernet cable.
Packaged in an easy-to-carry zipper pouch with RJ-11, RJ-45 and USB cables, as well as an AC adapter, it's as easy to carry as it is to use -- and it makes leveraging the full breadth of Internet services even easier.