Cable Testing:

This module covers cable testing and how different factors effect the performance of different types of network media.

Coaxial Cable: Type of shielded cable. Copper core with braided copper shield.

Vocabulary - Key Terms:

Wave: is energy that travels from one place to another




Square Wave: The wave maintains one value and then suddenly changes to a different value.



Oscilloscope: An important electronic device used to view electrical signals such as voltage waves and pulses. The x-axis on the display represents time and the y-axis represents voltage or current.



Noise: Noise related to communications refers to undesirable signals. Noise can originate from natural or technological sources and is added to the data signals in communications systems.



Wire Maps: This is what kind of wier organization you need to have to get T568A and T568B wiring


Ethernet Wire:


Attenuation- The decrease in signal amplitude over the length of a link.


Related Articles:
Cabel Testing 101
What you need to know about cables
Color Coding Cables


Key Concepts:
There are three important numbering systems
Base 2- Binary
Binary numbers have only two placeholders, which are zero and one.

Base10- Decimal
Decimal numbers have ten different placeholders, the numbers 0 to 9.

Base 16- Hexadecimal
Hexadecimal numbers have 16 different placeholders, the numbers 0 to 9 and the letters A to F.

The ten primary test parameters that must be verified for a cable link to meet TIA/EIA standards are:

• Wire map
• Insertion loss
• Near-end crosstalk (NEXT)
• Power sum near-end crosstalk (PSNEXT)
• Equal-level far-end crosstalk (ELFEXT)
• Power sum equal-level far-end crosstalk (PSELFEXT)
• Return loss
• Propagation delay
• Cable length
• Delay skew

Analog bandwidth- mesured in Hertz (Hz) i.e Radio station signals

Digital bandwidth- measures how much information can flow from one place to another in a given amount of time
Course Materials:

CCNA 1 - Module 4 - Study Guide (.pdf)