What Is Attenuation in Networking?

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When used by networking professionals, the word attenuation refers to the loss of signal strength due to external or internal factors. Let’s explore how attenuation occurs and what options are available to increase signal strength.

Definition of Attenuation in Networking

Attenuation is the loss of signal strength in networking cables or connections. This typically is measured in decibels (dB) or voltage and can occur due to a variety of factors. It may cause signals to become distorted or indiscernible. An example of this is Wi-Fi signal and strength getting noticeably weaker the further that your device is from the router. 

When measuring attenuation in a wired network, the greater the signal strength over a long distance, the more effective the cable is. Less efficient cables will struggle with signal attenuation, and networking administrators may need to adjust the cable or insert amplifiers or repeaters in order to boost the signal strength. However, the more signal amplifiers applied, the slower the signal speed will become between endpoints, due to the extra components that have been added. 

Attenuation can happen with any type of cable or wireless connection, including the following: 

  • Copper cables
  • Fiber cables
  • Satellite
  • Radio signals
  • Wireless networks

Attenuation Versus Amplification

While attenuation is the loss of signal strength, amplification boosts the strength of a signal. However, amplification can also affect the noise in the transmission, potentially degrading the quality of the signal. Noise can come in the form of electromagnetic frequencies, electrical currents, wire leakage or wireless signals.

In computer networking, internal software can help reduce the overall noise so that the signal isn’t too distorted. Management of both attenuation and amplification is among the key skills and troubleshooting tasks of networking professionals.

Amplification can happen in a few different ways. Network or signal repeaters are common methods of amplifying signals. Repeaters take in the signal being sent, process it and then send out the signal stronger than before to the next waypoint (either another repeater or the end user). 

Another method is signal boosters, which are common with wireless signals. Antennas typically work well with, or are required for, booster equipment. 

Domain name system (DNS) amplification is another method, but this is typically related to network security systems and is used to amplify the signal to confuse a target server by flooding it with data.

What Causes Signal or Cable Attenuation?

Listed below are some of the most common causes of signal attenuation.

Frequency and Noise

All networking and electrical cables give off an electromagnetic frequency within the cable or wireless vicinity. The more frequencies there are within a particular space, the more noise there is, which can further attenuate and hamper the signal’s strength.

Physical Surroundings

Besides the signal’s proximity to other cables or frequencies, the physical surroundings of a signal can also hamper its strength. Temperature, walls or other barriers, and wire insulation can all affect signal strength.

Cold temperatures can cause wires to become brittle and inflexible, which can also slow down or attenuate the signal. Hot temperatures can cause signals to overheat, potentially even catching fire if the outside plastic melts away and the inside wire is exposed to flammable materials. Either way, wire insulation and temperature control are important to preserve wire strength.


Finally, the distance between the signal’s source and the end user is also a potential cause for attenuation. The further a transmission has to travel, the more noise it can experience along the way, thus causing attenuation. Even wireless signals will begin to lose strength the farther the signal has to travel.

How Can Attenuation Be Prevented or Improved?

Attenuation can cause issues for businesses of all sizes – especially international businesses with multiple offices across the globe. However, signal attenuation can be prevented or improved with some easy adjustments. Below are some of the best methods available to modern businesses.

Improving Cables

Cables can come in many forms, including copper, fiber, satellite and more. Each type of cable can handle different rates of transmission and different temperatures.

Copper cables, although cheap and common, can be less effective and may experience attenuation more frequently that other types of cables. Fiber cables, however, use glass tubes and send signals through high-frequency wavelengths of light.

Switching cables from copper to fiber — as well as ensuring they are all properly insulated — can help improve a signal’s strength and speed.

Shortening Distance

A network administrator is not only responsible for networking the environment, but to maintain the best efficiencies possible. For example, using shorter cables, or moving the end product closer to the signal source, can also help improve signal strength. The faster the signal, the more productive and cost-efficient a company becomes.

Including Amplifiers or Repeaters

Although repeaters or amplifiers may slow down a signal, they do a great job at preventing attenuation. These options may work best in large offices or environments where the signal needs to reach farther, but the speed of the transmission is less important.

Ready to learn more? Download the exam objectives for CompTIA Network+ to see all the topics the exam covers and check out CompTIA CertMaster Learn to dive in.

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