Structured cabling systems for computer networks often rely on twisted-pair copper cables. These cables contain eight individual wires, twisted in pairs to mitigate electromagnetic interference. To ensure consistent connectivity, these wire pairs are arranged according to specific color conventions, known as T568A and T568B. T568A orders the pairs as green/white, green, orange/white, blue, blue/white, orange, brown/white, and brown. T568B uses a slightly different order: orange/white, orange, green/white, blue, blue/white, green, brown/white, and brown. Cables wired using the same standard at both ends are called “straight-through” and are used for typical network connections. “Crossover” cables, with different standards at each end, were previously used for direct computer-to-computer connections but are less common with modern network equipment.
Standardized wiring is essential for network reliability and interoperability. Adhering to these established color schemes simplifies troubleshooting, installation, and maintenance of network infrastructure. Without consistent wiring practices, connecting devices becomes challenging and prone to errors, resulting in network downtime and frustration. Historically, these standards arose from the need to ensure consistent communication between equipment from different manufacturers. This standardization allowed for a plug-and-play environment, fostering the growth of computer networks.