Patch Cords and Why you Need Them

Devices of different types, such as a switch connected to a computer, or switch to router are connected with patch cords. A patch cord (sometimes patch cable or patch cord) is an electrical or optical cable, used to connect ("patch-in") one electronic or optical device to another for signal routing.
Patch cables and patch cords are flexible cables that are terminated at both ends with a plug and used to interconnect circuits. These male/male cables and cords are used with patch panels, groups of ports that connect lines between communications and electronic devices. Patch cords are usually produced in many different colors so as to be easily distinguishable, and are relatively short, perhaps no longer than two meters.
There are many types of patch cables and patch cords. Choices include Cat 3, Cat 5, Cat 6, coaxial, triaxial and twisted pair and even more commonly known products such as microphone cables and headphone extension cables.
Patch cords are often made of coaxial cables, with a positive or "hot" signal carried through a shielded core, and the negative electrical ground or earthed return connection carried through a wire mesh surrounding the core. Each end of the cable is attached to a connector, so the cord may be plugged in. Types of connectors may vary widely, particularly with adapting cables. Patch cords can be as short as 3 inches or 8 cm, to connect stacked components, or route signals through a patch bay, or as much as twenty feet or 6 m or more in length for snake cables. As length increases, cables are usually thicker, and/or made with more shielding, to prevent signal loss and the introduction of unwanted radio frequencies and hum (electromagnetic interference).
Patch cords may be:
• single-conductor wires using, for example, banana connectors
• coaxial cables using BNC connectors
• Ethernet Cat5, Cat5e, or Cat6 cables using "RJ-45" connectors with TIA/EIA-568-A or TIA/EIA-568-B wiring
• Optical fiber cables
An infamous type of optical fiber cables that are labeled under patch cords are Fiber Optic Patch cords. These fiber optic patch cords are more and more used to transmit telecommunication signals than traditionally copper patch cords in the network. Compared with traditional copper patch cords, fiber optic patch cords features higher operation speed -up to 10 gigabit, broader bandwidth, which means it is with a larger capacity of carrying the signals, longer transmitting distance, better to the environment- no noise, no radios, and easier to maintain them.
Usually the fiber optic patch cord structure is like this: fiber glass in the center with cladding on it, this is called the "core”, around the core people put some other different materials to make the cables with different features, for example, more tension-resistant, waterproof, etc. the most outside layer which is called "jacket" of the cable usually is made of PVC, and there are different standards, for example, riser, plenum, ofnr, ofnp, etc. the most commonly used cables for making fiber patch cords are with 0.9mm outer diameter, or 3mm outer diameter, or 2mm outer diameter. 2mm outer diameter is the most commonly used in North America; they look smarter although they operate the same as 2mm and 0.9mm ones.
Typical types are simplex fiber optic patch cord and duplex fiber optic patch cord, a simplex patch cord means this patch cord is made of a single fiber cable, a duplex patch cord can be regarded as two simplex ones put side by side.