How Cable Aging Impacts Network Stability Over Time

 We tend to think of network infrastructure as static. Once you pull the wire through the wall, punch it down, and plug it in, the assumption is that it will work forever. Unlike a hard drive with moving parts or a battery that loses its charge, a copper wire seems like a permanent fixture.

However, Ethernet networking cables are subject to the same laws of physics and chemistry as everything else. They age. They degrade. And eventually, they fail.

Cable aging is a silent killer of network performance. It doesn't usually happen overnight with a dramatic "snap." Instead, it is a slow creep. A network that ran at 10 Gigabits five years ago might struggle to negotiate 1 Gigabit today. Packets start dropping. PoE devices reboot randomly.

Understanding the mechanics of cable aging—what causes it and how to prevent it—is essential for anyone managing a network that needs to last more than a few years. It is the difference between a "set it and forget it" install and a maintenance nightmare.

The Chemistry of Decay: Oxidation and Resistance

The heart of any Ethernet cable is the conductor. In high-quality cables, this is copper.

Copper is an excellent conductor, but it has a weakness: Oxygen. When copper is exposed to air, it reacts to form copper oxide (that greenish "patina" you see on old statues). While the plastic jacket protects the wire, no jacket is perfectly airtight forever.

Over 10 to 15 years, oxygen slowly permeates the insulation. If the cable was terminated poorly, leaving exposed copper at the jack, oxidation happens much faster.

Why does this matter? Copper oxide is a semiconductor, not a conductor. As the surface of the wire oxidizes, the electrical resistance increases. This creates a barrier for the high-frequency signals (data) traveling on the "skin" of the conductor. This is known as the Skin Effect. As resistance rises, the signal gets weaker (Attenuation), leading to intermittent connection drops.

The CCA Accelerator

If you used cheap CCA (Copper Clad Aluminum) cable, this aging process happens at warp speed. Aluminum oxidizes almost instantly when exposed to air. This oxidation layer is brittle and highly resistive. A CCA cable that works fine on Day 1 can often fail completely within 3 to 5 years just from the natural thermal expansion and contraction causing the brittle aluminum to crack.

To ensure your network survives the decade, you must use solid copper, such as a high-quality cat6 plenum solution. Pure copper resists this chemical breakdown far better than aluminum composites.

The Plastic Problem: Jacket Embrittlement

The insulation and the outer jacket of the cable are made of polymers (plastics). Plastics contain "plasticizers"—chemicals that keep the material flexible.

Over time, these plasticizers evaporate. This process is accelerated by:

1. Heat: Running cables in a hot attic or above a drop ceiling.
2. UV Light: Sunlight hitting a cable near a window.
3. Dry Air: Low humidity environments.

As the plasticizers leave, the jacket becomes brittle. If you touch an old cable, it might feel stiff. If you try to move it, the insulation inside can crack.

When the insulation between the twisted pairs cracks, the copper wires can touch. This causes a short circuit. Even if they don't touch, the change in the distance between the wires alters the Impedance of the cable.

• The Result: "Return Loss." The signal hits the anomaly in the cable and bounces back, confusing the router.

Using a robust Cat6 Plenum cable helps mitigate this. Plenum-rated jackets (often made of FEP or fluoropolymers) are chemically more stable and heat-resistant than standard PVC jackets, meaning they retain their flexibility and dielectric properties much longer.

Thermal Fatigue: The Expansion Cycle

Cables breathe. When data flows through them (and especially when Power over Ethernet is involved), they heat up. When the network is idle at night, they cool down.

This heating and cooling cycle causes the copper to expand and contract. Over thousands of cycles, this physical movement causes "metal fatigue."

In connectors, this movement can cause the wire to slowly work its way out of the "teeth" of the jack, leading to a loose connection. This is often why wiggling a cable seems to fix the internet temporarily.

For networks running high-power devices (like PTZ cameras or Wi-Fi 6 access points), the thermal load is higher. Choosing a Cat6A Plenum Cable is a smart move for longevity. Cat6a has thicker copper conductors (23 AWG) which handle heat better, reducing the physical stress on the cable over time.

Gravity and Creep: Vertical Aging

In multi-story buildings, cables run vertically through riser shafts. Gravity is a constant force acting on these suspended cables.

Over time, the weight of the copper pulls on the jacket. This is called "Cold Flow" or "Creep." The copper conductors can actually stretch inside the jacket.

When an Ethernet cable stretches, the "twist rate" (the number of twists per inch) changes. Since the twists are there to cancel out interference, a stretched cable loses its immunity to noise.

To prevent this aging factor, you must use cat 6 riser cable. These cables are engineered with higher tensile strength to withstand the pull of gravity without deforming internally. Proper installation—using strain relief and cable supports every few feet—is also critical to fighting gravity.

Environmental Attack: The Outdoor Factor

The fastest way to age a cable is to expose it to the elements.

Standard indoor cables are porous to water vapor. If you run a regular grey patch cord outside, UV rays will crack the jacket within months. Once the jacket cracks, rain enters.

Water changes the electrical properties of the cable instantly. It increases the "capacitance," which kills the high-frequency data signal. Even worse, water wicks down the cable into your building, corroding the switch port.

For any run that is not climate-controlled, you need direct-burial cable. These feature a UV-immune LLDPE jacket and often a gel-filling that blocks water ingress, stopping environmental aging in its tracks.

The Weakest Link: Connector Corrosion

Often, the cable itself is fine, but the ends have failed.

The RJ45 plug and the keystone jack rely on gold-plated pins to make contact. Gold is used because it doesn't oxidize. However, to save money, cheap manufacturers use a very thin layer of gold "flash" plating.

After a few years of humidity and tiny vibrations (from fans or footsteps), that thin layer of gold wears off, exposing the nickel or copper underneath. This base metal oxidizes, creating a high-resistance connection.

• Symptom: The link light flickers, or the speed drops from 1Gbps to 100Mbps.

Investing in high-quality ethernet cable accessories with 50-micron gold plating ensures that the contact points remain corrosion-free for the life of the installation.

Installation Stress: The Time Bomb

Sometimes, aging is actually just "delayed failure" caused by bad installation.

If an installer pulls a cable too hard (stretching it) or kinks it around a corner, they create a micro-fracture in the copper. At the time of install, the copper is still touching, so the test passes.

But over five years, as the building vibrates and the temperature cycles, that micro-fracture grows. Eventually, the wire snaps internally.

Using proper installation tools and spools, like a Black Cat6a Plenum on a wooden drum, ensures the cable is deployed without stress. This prevents the microscopic damage that turns into a network outage years later.

Is Fiber Immune?

Since copper corrosion is the main enemy, is fiber optic cable the solution?

Mostly, yes. Glass does not corrode. It does not oxidize. However, fiber has its own aging issues. "Hydrogen Darkening" can occur over decades where hydrogen atoms seep into the glass, clouding it. But generally, a fiber link is significantly more stable over a 20-30 year lifespan than copper, provided the physical connectors are kept clean.

Building for the Long Haul

Cable aging is inevitable, but it can be managed. You cannot stop physics, but you can choose materials that resist it.

By selecting CAT6 Plenum TAA Compliant ETL/UL Listed Cable, you start with pure copper and high-grade insulation that degrades much slower than the cheap alternatives.

Think of your cabling like the plumbing in your house. You don't want to replace it every five years. You want it to last as long as the building stands. By investing in quality infrastructure from NewYork Cables, you ensure that your network remains fast, stable, and reliable—long after the "new cable smell" has faded.