Introduction – Why Armor Matters More Than You Think

Every optical fiber cable project faces the same critical question: should you choose an armored cable or a non-armored one?

At first glance, the choice may look simple. Armored cables appear stronger, non-armored cables are cheaper. But the real decision is not that easy. The wrong choice can:

• Shorten your network’s service life by years,
• Lead to costly repairs and unexpected downtime,
• Cause regulatory or safety compliance failures,
• Or simply make installation impossible in your environment.

The protective structure of a cable—whether armored or not—is not just a technical detail. It is a strategic design choicethat impacts performance, costs, and long-term reliability.

Imagine three different projects:

1. A metro backbone under a busy city street.
2. A hyperscale data center with thousands of racks.
3. A telecom operator rolling out FTTH in rural villages.

Each project needs fiber, but the cable armor decision will be completely different. Choosing the wrong cable type can turn a well-designed plan into a maintenance nightmare.

Key takeaway: Armor is not just steel wrapped around a cable. It is a decision about how your fiber will survive in the real world.

What Is an Armored Optical Cable?

An armored optical cable is a type of fiber optic cable reinforced with a protective layer—usually corrugated steel tape (STA) or steel wires (SWA)—to shield the internal fibers from external threats such as crushing, rodent bites, moisture, and harsh installation conditions.

Structural Features of Armored Cables

• Core: Optical fibers (single-mode or multi-mode) arranged in loose tubes or tight-buffered bundles.
• Strength Members: Aramid yarns, FRP rods, or metallic wires for tensile strength.
• Armoring Layer:
  • Steel Tape Armored (STA): Corrugated steel tape wrapped around loose tubes, offering radial compression resistance.
  • Steel Wire Armored (SWA): Layers of steel wires providing superior tensile and impact resistance.
  • Double Armored: Combination of tape and wire, used in submarine or mining cables.
• Outer Jacket: PE, LSZH, or PVC material depending on application and fire safety requirements.

Mechanical Advantages

• Crush Resistance: Withstands heavy loads in ducts, tunnels, or direct burial.
• Rodent Protection: Prevents damage from rats, termites, and other pests.
• Longevity: 20–30 years of reliable service in harsh environments.
• Water and Moisture Barrier: Steel layers prevent water ingress and swelling.

Typical Applications

• Underground metro networks (where heavy vehicles may pass overhead).
• Rural backbone routes (with rodent threats).
• Industrial plants and seaports (vibration, machinery, salt fog).
• Defense and subsea cables (double-armored versions).

Limitations of Armored Cables

• Heavier and more rigid—harder to handle in tight bends or ducts.
• Higher initial cost (20–30% more than non-armored).
• May require larger conduits or stronger support structures.

What Is a Non-Armored Optical Cable?

A non-armored optical cable is a fiber optic cable without any metallic armor layer. Instead, it relies on its jacket materials and non-metallic strength members (like aramid yarn or FRP rods) to provide basic mechanical protection.

Structural Features of Non-Armored Cables

• Core: Optical fibers in loose tube or tight-buffered form.
• Strength Members:
  • FRP (Fiber Reinforced Plastic): Non-metallic rods that prevent buckling.
  • Aramid Yarn (Kevlar): Provides tensile strength and protects against stress.
• Jacket:
  • PVC (Polyvinyl Chloride): Cost-effective, flexible, common for indoor use.
  • LSZH (Low Smoke Zero Halogen): Compliant with European fire codes, produces minimal toxic smoke.
  • PE (Polyethylene): Durable, resistant to UV, suitable for outdoor ducts.

Advantages of Non-Armored Cables

• Lightweight: Easy to handle, transport, and install.
• Flexible: Can bend around corners, ideal for indoor routing.
• Low Cost: Cheaper than armored designs (20–30% savings upfront).
• Code Compliance: Available in OFNR/OFNP/LSZH jackets for building standards.

Limitations of Non-Armored Cables

• No Rodent Protection: Vulnerable to bites and chewing damage.
• Low Crush Resistance: Susceptible to being crushed in ducts or underground.
• Shorter Lifespan in Harsh Environments: Typically 10–15 years outdoors without extra conduit protection.

Typical Applications

• Indoor Data Centers: LSZH riser and plenum cables.
• FTTH Drops (Inside Buildings): Flat or round LSZH cables for wall mounting.
• Enterprise Networks: Structured cabling inside offices.
• Short-Distance Outdoor Runs: Only when inside protective conduits.

Detailed Comparison – Armored vs Non-Armored

Feature	Armored Optical Cable	Non-Armored Optical Cable
Mechanical Strength	High (crush, tensile, rodent resistant)	Moderate (relies on FRP/aramid, jacket)
Weight	Heavy, bulky	Light, compact
Flexibility	Rigid, large bend radius	Flexible, small bend radius
Installation	Harder in ducts or risers	Easy to handle and pull
Cost (Initial)	Higher (20–30% more)	Lower upfront
Lifecycle Cost	Lower in harsh environments (fewer repairs)	Higher if exposed to rodents or crushing
Service Life	20–30 years in outdoor/industrial	10–15 years indoors, less outdoors
Common Jackets	PE, PVC, LSZH	PVC, LSZH, PE (light duty)
Best Applications	Underground, ports, rural, industrial	Data centers, indoor FTTH, conduits

Application Matrix (Environment vs Recommended Cable)

Environment	Recommended Cable Type	Why
FTTH Indoor	Non-armored LSZH flat drop	Flexible, meets fire code, low cost
Metro Underground	Armored STA	Crush resistant, protects against rodents
Direct Burial (Rural)	Armored SWA or Double Armored	High rodent activity, soil pressure
Data Center	Non-armored LSZH or OFNP	Lightweight, high density, fire safe
Industrial Port/Factory	Armored double layer	Resists vibration, impact, salt fog
Aerial ADSS Lines	Armored ADSS with steel messenger	Withstands wind, birds, rodents

Application Scenarios – Where Armored and Non-Armored Cables Make or Break Projects

Fiber optic cables serve in every environment imaginable—from underground tunnels beneath European cities to dusty industrial zones in Africa, to hyperscale data centers in North America. Each scenario demands a different level of mechanical protection.

1. FTTH Drop Cables (Residential Access)

Best choice: Non-armored flat drop or round LSZH cables.

• Why: FTTH installations usually pass through indoor risers, walls, or conduits. The environment is relatively safe, and flexibility matters more than armor.
• Typical Specs: G.657.A2 fibers, LSZH jacket, 1–2 FRP rods for strength.

Global Case Examples:

• East Asia: Urban high-rise FTTH rollouts in China, South Korea, and Singapore rely heavily on non-armored LSZH drop cables to comply with strict fire safety codes.
• Southern Europe: Operators in Spain and Italy often use flat LSZH drop cables with adhesive backs for easy indoor wall routing.
• South America: In countries like Chile and Colombia, FTTH installers choose non-armored cables for apartments but switch to armored drops in rural houses where rodents are common.

Key takeaway: Non-armored dominates FTTH, but rural areas with rodents or exposed ducts may still require light armor.

2. Underground & Metro Backbone Networks

Best choice: Armored STA or SWA cables.

• Why: Underground ducts and metro routes face high crush risks, moisture, and rodent attacks. Armored cables ensure long service life and reduce maintenance.
• Typical Specs: Steel tape armor with PE jacket, water-blocking gel or dry tube.

Global Case Examples:

• Northern Europe: Cities like Berlin and Stockholm prefer STA armored cables for metro fiber routes—high crush resistance protects cables from subway vibrations.
• Africa: In Kenya and Nigeria, rural backbones suffered repeated rodent bites. After switching to STA armored designs, failure rates dropped by 70%.
• North America: U.S. metro fiber projects in New York and Chicago adopt armored loose-tube cables with corrugated steel tape to withstand heavy construction activity.

Key takeaway: For any buried or metro backbone cable, armor is an insurance policy against costly repairs.

3. Industrial and Port Environments

Best choice: Double-armored or SWA cables.

• Why: Factories, oil refineries, and seaports expose cables to extreme mechanical stress—heavy machinery, chemicals, and salt fog. Armor is mandatory.
• Typical Specs: Steel wire or double-layer armor, PE outer jacket with anti-corrosion treatment.

Global Case Examples:

• Middle East: Ports in Saudi Arabia and UAE deploy double-armored cables for crane and container terminal networks. They resist vibration and saltwater exposure.
• Latin America: A Brazilian steel plant upgraded from non-armored to armored cables after repeated failures caused by forklifts crushing conduits.
• South Asia: Indian railways use SWA armored cables along tracks to withstand vibration and prevent rodent damage.

Key takeaway: In industrial or port zones, choosing non-armored is a false economy—repairs cost far more than armor.

4. Data Centers

Best choice: Non-armored LSZH or OFNP indoor cables.

• Why: In data centers, space and flexibility are more critical than heavy protection. Non-armored cables save weight and allow high-density routing.
• Typical Specs: Tight-buffer or ribbon cables, LSZH or plenum-rated jacket, aramid yarn for tensile strength.

Global Case Examples:

• North America: Hyperscale operators in the U.S. standardize on non-armored OFNP cables in white space areas. Fire codes and bend radius compliance drive decisions.
• Western Europe: Data centers in Frankfurt and Amsterdam use LSZH riser-rated cables in structured cabling systems, avoiding metal armor to reduce weight load in trays.
• East Asia: Japanese and South Korean data centers favor non-armored MPO/MTP trunk cables for high-density cross-connects.

Key takeaway: For data centers, armor adds no value—it only adds bulk.

5. Special Applications (Defense, Mining, Subsea)

Best choice: Double-armored or customized armored designs.

• Why: Harshest environments require extreme protection. Mining shafts, offshore oil platforms, and subsea routes expose cables to crushing, corrosion, and rodent-like marine life.
• Typical Specs: Double steel armor, copper tube sheathing, water-blocking gel, UV-stable PE jacket.

Global Case Examples:

• Defense: Military field-deployable reels often use lightweight tactical armored cables with aramid and stainless steel braiding.
• Mining (Australia, South Africa): Double-armored designs are deployed in underground mines, resisting crushing and corrosive gases.
• Subsea (Global): International submarine backbones use double-armored layers near shore landing zones to protect against fishing trawlers and anchors.

Key takeaway: Extreme environments leave no choice—armor is mandatory.

International Standards & Codes for Fiber Optic Cables

When choosing between armored and non-armored optical cables, compliance with international standards is just as important as mechanical performance. Different regions enforce different requirements, and ignoring them can result in project delays, regulatory fines, or forced reinstallation.

1. IEC 60794 – The Global Benchmark

The IEC 60794 series defines the mechanical, environmental, and test methods for optical fiber cables.

• IEC 60794-1-2: General test methods (tensile, crush, bending, impact).
• IEC 60794-3: Outdoor cables, including armored and non-armored.
• IEC 60794-2: Indoor cables (often non-armored LSZH).

👉 Procurement managers should request suppliers to provide IEC 60794 compliance reports to ensure the cable passed crush, tensile, and rodent tests.

2. ITU-T Recommendations – Fiber Core Standards

While IEC focuses on cable construction, ITU-T defines the optical fiber itself:

• G.652D: Standard singlemode fiber (commonly used in both armored and non-armored cables).
• G.657A1/A2/B3: Bend-insensitive fibers, ideal for FTTH and indoor non-armored drops.
• G.655: Non-zero dispersion-shifted fibers, used in long-haul armored backbones.

👉 The type of fiber (G.652 vs G.657) often determines whether a cable is armored or not, based on bend radius and deployment environment.

3. TIA/EIA-568 – North American Structured Cabling

In North America, the TIA/EIA-568 standard governs structured cabling inside buildings.

• Armored cables are rarely used indoors, except in risers or basements.
• Non-armored LSZH or plenum-rated cables dominate.
• Connectors, patch cords, and cable assemblies must meet TIA-568 performance specs.

4. Fire Safety & Building Codes

Fire safety is a critical compliance factor for indoor cables:

• OFNP (Optical Fiber Non-conductive Plenum): Highest rating, required in U.S. plenum spaces.
• OFNR (PVC): For vertical shafts between floors.
• LSZH (Low Smoke Zero Halogen): Mandatory in Europe, Middle East, and Asia for indoor cabling.

👉 Choosing the wrong fire rating can block cable approval during building inspections.

5. Regional Compliance Differences

• Europe: LSZH is mandatory for indoor use. CPR (Construction Products Regulation) classifies cables under fire performance classes (Eca, Dca, Cca).
• North America: OFNP/OFNR ratings dominate. Metallic armored cables may require grounding under NEC (National Electrical Code).
• Middle East & Africa: Many projects adopt European LSZH standards but add extra specifications for armored outdoor cables in harsh climates.
• Asia-Pacific: Rapid FTTH growth relies heavily on G.657A2 fibers with LSZH jackets indoors, but armored PE jackets outdoors.

📌 Compliance Tip for Buyers:
Always request the following documents from suppliers:

• IEC 60794 type test reports.
• ITU-T fiber certification (G.652/G.657).
• Fire rating certificates (LSZH/OFNP/OFNR).
• Country-specific CPR or NEC compliance.

Global Case Studies – How Armor Decisions Play Out in the Real World

1. Europe – Metro Underground Network in Germany

A major telecom operator in Germany deployed a metro backbone network in Berlin, running through underground tunnels and metro lines.

• Initial Issue: Non-armored cables suffered repeated crushing damage from maintenance equipment and heavy underground traffic.
• Solution: Upgraded to STA armored cables with corrugated steel tape.
• Result: Failure rate dropped by 80%, and the operator saved an estimated €500,000 per year in repair costs.

Lesson: In dense urban areas, armor is essential for long-term reliability.

2. Asia – FTTH Rollout in South Korea

South Korea, one of the world’s most fiber-connected countries, expanded FTTH networks in high-rise residential areas.

• Choice: Non-armored LSZH flat drop cables for indoor risers and apartment units.
• Reason: Fire code compliance and need for flexibility in tight ducts.
• Result: Faster installation speed and lower per-unit costs, while still meeting G.657A2 bend radius requirements.

Lesson: In safe indoor environments, non-armored LSZH is the clear choice.

3. Africa – Rural Backbone in Kenya

A national telecom operator in Kenya rolled out a rural backbone spanning thousands of kilometers.

• Problem: Non-armored cables were frequently chewed by rodents in underground ducts.
• Upgrade: Switched to SWA armored cables with steel wire reinforcement.
• Outcome: Rodent-related failures dropped from 15% annually to less than 2%, reducing truck rolls and service downtime.

Lesson: In rural areas with high rodent activity, armor quickly pays for itself.

4. North America – Hyperscale Data Center in the U.S.

A hyperscale data center in Virginia, part of the largest data hub in the world, needed a lightweight, flexible cabling system.

• Choice: Non-armored OFNP cables, plenum-rated for air handling spaces.
• Reason: High cable density in trays required reduced weight and bend flexibility.
• Result: Achieved 25% space savings and simplified cable management without sacrificing safety.

Lesson: In data centers, non-armored cables are standard due to weight and density considerations.

5. Middle East – Industrial Port in Saudi Arabia

A port authority in Saudi Arabia needed to upgrade fiber networks for cranes, terminals, and security systems.

• Problem: Previous non-armored cables failed due to salt fog, heavy vehicles, and vibration.
• Solution: Installed double-armored submarine-style cables with PE jackets.
• Result: Network has operated 8+ years without major maintenance, even under harsh desert and marine conditions.

Lesson: Industrial and port environments demand heavy armor for long service life.

6. Latin America – FTTH Expansion in Chile

A telecom company in Chile rolled out FTTH in suburban and rural homes.

• Strategy:
  • Non-armored LSZH cables inside buildings.
  • Armored flat drops for outdoor routes exposed to rodents and moisture.
• Result: Balanced cost optimization with reliability, reducing maintenance calls by 40% in rural deployments.

Lesson: Hybrid strategies (armored outdoors, non-armored indoors) can deliver the best ROI.

Cost & ROI Analysis

Choosing between armored and non-armored optical cables is not only a technical decision but also a financial one.

Initial Cost Differences

• Armored cables: typically 20–30% more expensive upfront.
• Non-armored cables: cheaper, but may require protective conduits, increasing indirect costs.

Maintenance Cost Impact

• Armored cables significantly reduce failures from rodents, crushing, or environmental stress.
• Non-armored cables in harsh environments often require frequent repairs.

📊 Example Calculation:

• 100 km underground route.
• Non-armored saves ~$50,000 initially.
• But if rodent/crush failures occur: 5 repairs/year × $8,000/repair = $40,000 annually.
• Within 2 years, armored cables offset their higher cost.

ROI Takeaway

• Armored = best ROI for outdoor, rural, or industrial environments.
• Non-armored = best ROI for data centers, FTTH indoor drops, or conduits.

Procurement Checklist

Before placing an order, procurement managers should review:

1. Deployment Environment – Indoor / Outdoor / Metro / Rural / Industrial / Subsea.
2. Mechanical Risks – Crush, rodent, vibration, heavy equipment.
3. Compliance – IEC 60794, ITU-T G.652/G.657, OFNP/LSZH fire codes.
4. Armor Type – STA, SWA, Double armored, or non-armored.
5. Fiber Type – G.652D, G.657.A2, OM3/OM4 depending on distance and bandwidth.
6. Jacket Material – PVC (indoor), LSZH (fire safe), PE (outdoor).
7. Packaging & Logistics – Wooden reels, palletization, labeling, container loading.
8. Supplier Proof – Test reports, compliance certificates, inspection photos.

👉 A procurement checklist like this ensures projects stay on budget, compliant, and future-proof.

 FAQ

Q1. Does armor reduce optical performance?
No. Armor only affects mechanical strength; the fiber core performance remains unchanged.

Q2. Can I use armored cables indoors?
Yes, but they are heavy and rigid. Non-armored LSZH is usually preferred indoors.

Q3. Which cable should I use for aerial installations?
Armored ADSS or figure-8 style cables with steel messengers are ideal.

Q4. Are non-armored cables always cheaper?
Upfront yes, but lifecycle costs may be higher in harsh environments.

Q5. What’s the best option for ports or railways?
Double-armored cables with PE jackets—high vibration and rodent risk demand maximum protection.

Q6. Do armored cables require grounding?
Yes, in some regions (e.g., NEC in North America) metallic armor must be properly grounded.

Q7. Can I order customized armor?
Yes, hybrid designs (steel + aramid) are available for specific applications.

Q8. How do I confirm compliance?
Request IEC 60794 and ITU-T test reports from suppliers.

Future Trends in Armored and Non-Armored Cables

The fiber cable market continues to evolve:

• Lightweight Armor: Non-metallic armor (FRP, Kevlar braiding) reduces weight while maintaining strength.
• Eco-Friendly Jackets: LSZH and halogen-free PE are gaining traction due to green regulations.
• Smart Monitoring: Some new designs embed sensors into armored cables to detect strain, moisture, or cuts in real time.
• Hybrid Designs: Combining armored outdoor segments with non-armored indoor drops for cost-performance balance.

Key takeaway: The future is about balance—lighter, greener, smarter fiber designs.

 Conclusion

Armored and non-armored cables are not competitors but complements. Each has its place:

• Armored cables are the shield—built for survival in harsh outdoor, rural, industrial, and subsea environments.
• Non-armored cables are the agile performers—light, flexible, and cost-efficient for indoor, data center, and protected routes.

Choosing the right one requires understanding:

• The environment,
• The standards,
• The lifecycle costs,
• And the long-term reliability.

When chosen correctly, fiber cables deliver decades of reliable service. When chosen poorly, they become a recurring cost burden.

👉 For projects worldwide—whether FTTH, data centers, industrial ports, or national backbones—HOLIGHT offers both armored and non-armored solutions, tested to IEC and ITU standards, customizable for your environment.

Call to Action

Looking for armored and non-armored optical cables tailored for your project?

👉 Visit www.holightoptic.com and www.ftthfiberoptic.com to explore our product range, download specifications, and request expert consultation.