What’s the Difference Between 568A and 568B?

You probably don’t think much about the cables behind your walls—until your network starts acting up. But when it comes to structured cabling, one overlooked detail can cause major problems: the difference between 568A and 568B wiring standards.

At Kommvia, we’ve been wiring offices across Indiana, Chicago, and Southern Michigan for years. We know that when it comes to network reliability, details matter.

Let’s break it down.

What’s the Difference Between 568A and 568B?

Both standards define how the eight wires in an Ethernet cable connect to an RJ45 jack. The only difference? The position of the green and orange wire pairs.

• 568A: Green pair goes to pins 1 & 2; orange to pins 3 & 6.
• 568B: Orange pair goes to pins 1 & 2; green to pins 3 & 6.

Functionally, both work the same. But mixing them up—or switching mid-install—can lead to serious connectivity issues. Choose one and stick with it across your entire network.

A Quick History

Back in the early ’90s, the Telecommunications Industry Association (TIA) created these standards to eliminate messy, inconsistent wiring practices.

• 568A (1991): Became the federal/government go-to due to its alignment with global cabling standards.
• 568B (1995): Took off in the U.S. because it mirrored how most networks were already being wired.

Today, they both remain valid—but the choice depends on your project scope.

Which Standard Should You Use?

• Commercial Buildings & U.S. Installations: 568B is the dominant choice.
• Government Projects or International Builds: 568A is often required.
• Crossover Cables: Use both—568A on one end, 568B on the other.

Bottom line: There’s no “better” standard—only the right one for your job. What matters most is consistency.

Why It Matters

Mismatched terminations, messy patch panels, and disorganized cable closets can cause downtime and confusion. That’s where Kommvia comes in.

We design and install structured cabling systems that are:

✔️ Clean

✔️ Code-compliant

✔️ Fully documented

✔️ Consistently terminated

From small business offices to multi-site installations, we make sure your infrastructure is built to perform.

Trust Kommvia to Wire It Right

Whether you’re building out a new location, upgrading your cabling, or just cleaning up the last guy’s mess—we’ve got you covered.

🛠 Structured Cabling

📞 Business Phone Systems

🔧 PBX Troubleshooting & Installation

🌐 Commercial Network Solutions

Serving Northern Indiana, Chicago, and Southern Michigan.

Let’s get your network done right—start to finish.

📞 Call 844-KOMMVIA

📩 Email go@kommvia.com

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