A Coaxial cable is a type of network cable that carries electrical signals through a single central copper conductor, surrounded by insulation and shielding.
👉 The word Coaxial means both conductors share the same axis.
• Inner conductor and outer shield are aligned on the same axis
• This design helps reduce signal interference
A coaxial cable has 4 layers:
1️⃣ Inner Copper Conductor
• Carries the data signal
2️⃣ Dielectric Insulator
• Separates inner conductor and shield
• Prevents signal loss
3️⃣ Metallic Shield (Braid/Foil)
• Protects from EMI & noise
• Acts as ground
4️⃣ Outer Plastic Jacket
• Protects cable physically
• Transmits electrical data signals
• Reduces electromagnetic interference (EMI)
• Provides stable signal over medium distances
• Protects signal from external noise
1️⃣ Thick Coaxial Cable (Thicknet)
• Diameter is large
• Used in early Ethernet networks
• Supports longer distance
• Difficult to install
Example: 10Base5
• Smaller and flexible
• Easier to install
• Shorter distance
Example: 10Base2
• Bayonet Neill–Concelman
• Used to connect coaxial cable to devices
• Provides secure connection
Other connectors:
• F-type (Cable TV)
• N-type (Radio communication)
• 📺 Cable Television (DTH)
• 📷 CCTV camera systems
• 🌐 Broadband internet (older systems)
• 📡 Radio & antenna systems
• 🖥 Early LAN Ethernet networks
• Better shielding than twisted pair
• Less affected by EMI
• More durable
• Suitable for analog signals
• Bulky and heavy
• Difficult to manage
• Lower speed than fiber
• Mostly obsolete in modern LANs
• Speed: Medium
• Distance: Medium
• Security: Moderate
• Cost: Medium
| Feature | Coaxial | Twisted Pair |
| Shielding | High | Low–Medium |
| Flexibility | Low | High |
| LAN usage today | Rare | Very common |
• Uses single copper conductor
• Protected by metallic shielding
• Uses BNC connector
• Older Ethernet technology
• More resistant to noise than UTP
👉 Coaxial = TV + CCTV + Old Ethernet
If interviewer asks:
👉 “What is a coaxial cable?”
Say confidently:
A coaxial cable is a communication cable that uses a single copper conductor surrounded by insulation and shielding to transmit electrical signals with reduced interference, commonly used in cable TV and CCTV systems.
