Network Cabling Standards

Introduction to Cabling Standards

• Networks across organizations have standardized methods for installation.
• Colors and methods are consistent due to international standards.

Standards Organizations

• ISO/IEC 11801: International standard for cabling.
• TIA (Telecommunications Industry Association): U.S. based; TIA 568 standard covers commercial building telecommunications cabling.
  • Details available at TIA Online

TIA 568 Standard

• Focuses on pin and pair assignments for Ethernet connections.
• Known as T568A and T568B standards.
• Relevant for eight-conductor, 100-ohm balanced twisted pair cabling.

Pin and Pair Assignments

• Two standards for Ethernet RJ45 connector or punch-down block:
  • T568A
  • T568B
• 8P8C Connectors: Eight positions, eight conductors.

Usage in Organizations

• T568A is common in horizontal cabling.
• T568B is often used for end-user connections.
• Functionality: Both standards are functionally equivalent.

Crossover Cables

• Misconception: Crossover cable is T568A on one side, T568B on the other.
• Correct standard for crossover cables is defined by IEEE.
• T568 standards do not apply to Ethernet crossover cables.

Color Schemes

T568A

• Pin 1: White/Green
• Pin 2: Green
• Pin 3: White/Orange
• Pin 6: Orange

T568B

• Pin 1: White/Orange
• Pin 2: Orange
• Pin 3: White/Green
• Pin 6: Green

Common Pins

• Pins 4, 5, 7, 8: Same in both standards

Identifying Standards

• Check the back of an Ethernet cable for color coding.
  • Example: Orange colors on pins 1 and 2 could indicate T568B.

Installation Example

• Punchdown blocks may show both A and B color schemes.
• Install by matching the wire colors to the scheme used (A or B).
• Blue and brown wires remain consistent across both standards.

Summary

• Organizations may have preferences but both standards are valid.
• Proper installation requires adherence to color-coded standards.