Why Are Some Ethernet Cables Yellow? Here's What It Means
If you've ever wondered what the lights mean on an Ethernet port, you may have also been curious as to why the cables are different colors. While not all Ethernet cables look the same, that's not just a matter of style. The color of a cable often has a deeper meaning, especially in professional or network-heavy environments. Yellow, in particular, tends to stand out and often for a reason that goes beyond what you can see.
Yellow Ethernet cables are commonly associated with Power over Ethernet (PoE) connections, a standard introduced in 2009 by the Institute of Electrical and Electronics Engineers (IEEE). Capable of transmitting both power and data, yellow cables used with twisted-pair Ethernet can deliver up to 30 watts directly through the port. Yellow Ethernet cables can be easily identified thanks to their color, enabling quicker troubleshooting when needed.
Yellow Ethernet cables are also often connected to desktop computers or can be used in environments where internal systems need to be kept separate from public networks. This includes corporations and government facilities, where the IT staff can quickly and easily manage the traffic between secure and non-secure zones.
Differently colored Ethernet cables often serve different purposes
Ethernet cables are often colored differently to indicate their intended use, from internet to gaming, but the colors themselves don't necessarily mean that one cable is better or faster than another. While the Telecommunications Industry Association has designated specific color codes, those codes aren't always followed, which means different countries may use many different color configurations. But there are a few colors other than yellow that consistently serve similar specific functions, despite where they're used.
Blue Ethernet cables are commonly used to connect terminal servers, allowing multiple devices to interface with a single Local Area Network (LAN). Green Ethernet cables are often used for crossover connections, enabling direct communication between devices, such as linking two computers or switches. Gray Ethernet cables are typically used as the default choice for standard network connections and are commonly found in both residential and commercial settings.
Wiring companies regularly use these colors, as well as white and orange, for their interior Ethernet cables. But for exterior wiring, a waterproof black covering is generally used to protect the long Ethernet cables that run outside from all sorts of weather conditions.