Cables & Connectors
Key Takeaways
- Cat 5e supports Gigabit Ethernet (1 Gbps) up to 100 meters, Cat 6 supports 10 Gbps up to 55 meters, and Cat 6a supports 10 Gbps up to the full 100 meters.
- Fiber optic cables come in single-mode (long distance, up to 100+ km, yellow jacket) and multimode (shorter distance, up to 2 km, orange/aqua jacket).
- Straight-through Ethernet cables connect different types of devices (PC to switch), while crossover cables connect same types (PC to PC, switch to switch) — modern devices with Auto-MDI-X eliminate this distinction.
- Coaxial cable types include RG-6 (cable TV/internet, 75 ohm) and RG-59 (short runs, legacy CCTV); both use F-type connectors.
- DisplayPort supports daisy-chaining multiple monitors from a single port, while HDMI does not — this is a key differentiator for multi-monitor setups.
Last updated: March 2026
Cables & Connectors
Network Cables (Copper)
Ethernet Cable Categories
| Category | Max Speed | Max Distance (Full Speed) | Shielding | Common Use |
|---|---|---|---|---|
| Cat 5 | 100 Mbps | 100m | Unshielded (UTP) | Legacy — avoid for new installations |
| Cat 5e | 1 Gbps | 100m | UTP | Most common in existing installations |
| Cat 6 | 10 Gbps | 55m (1 Gbps at 100m) | UTP or STP | New installations, offices |
| Cat 6a | 10 Gbps | 100m | STP (Shielded) | Data centers, high-performance |
| Cat 7 | 10 Gbps | 100m | Fully shielded (S/FTP) | Data centers, industrial |
| Cat 8 | 25/40 Gbps | 30m | Fully shielded (S/FTP) | Data centers, server rooms |
Exam Tip: The maximum distance for all copper Ethernet cables is 100 meters (328 feet). Beyond that, you need a repeater, switch, or fiber optic cable.
Ethernet Cable Types
| Cable Type | Wiring | Use Case |
|---|---|---|
| Straight-through | T-568B on both ends | PC to switch, PC to router, router to switch |
| Crossover | T-568A on one end, T-568B on the other | PC to PC, switch to switch, router to router |
| Rollover (Console) | Reversed pin-out | PC serial port to router/switch console port |
Note: Most modern devices support Auto-MDI-X, which automatically detects the cable type and adjusts. Crossover cables are rarely needed with modern equipment.
Ethernet Connector
- RJ-45 — Standard 8-pin modular connector for Ethernet cables
- RJ-11 — Smaller 6-pin connector for telephone lines (DO NOT confuse with RJ-45)
Fiber Optic Cables
| Type | Core Diameter | Wavelength | Max Distance | Jacket Color | Use Case |
|---|---|---|---|---|---|
| Single-Mode (SMF) | 8–10 μm | 1310/1550 nm | Up to 100+ km | Yellow | WAN, long-distance, telco |
| Multimode (MMF) | 50/62.5 μm | 850/1300 nm | Up to 2 km | Orange or Aqua | LAN, data centers, buildings |
Fiber Connectors
| Connector | Description |
|---|---|
| SC (Subscriber Connector) | Square push-pull connector; common in enterprise |
| LC (Lucent Connector) | Smaller latching connector; most common in modern deployments |
| ST (Straight Tip) | Round bayonet-style connector; legacy installations |
| MTRJ | Small dual-fiber connector; less common |
Memory Aid: SC = Square Connector, LC = Little Connector, ST = Straight Tip
Coaxial Cable
| Type | Impedance | Use Case |
|---|---|---|
| RG-6 | 75 ohm | Cable TV, cable internet, satellite |
| RG-59 | 75 ohm | Short runs, legacy CCTV, patch cables |
Connector: F-type connector (screw-on) for both RG-6 and RG-59, BNC connector (bayonet) for some video applications.
Video Cables & Connectors
| Connector | Type | Max Resolution | Audio | Notes |
|---|---|---|---|---|
| HDMI | Digital | 8K@60Hz (HDMI 2.1) | Yes | Most common; consumer standard |
| DisplayPort | Digital | 8K@60Hz (DP 2.0) | Yes | Supports daisy-chaining; preferred for multi-monitor |
| USB-C (Alt Mode) | Digital | 8K@60Hz | Yes | Uses DisplayPort or HDMI Alt Mode |
| DVI-D | Digital only | 2560x1600 (Dual-Link) | No | Legacy; being phased out |
| DVI-I | Digital + Analog | 2560x1600 (Dual-Link) | No | Legacy; supports VGA adapter |
| VGA (DE-15) | Analog | 2048x1536 | No | Legacy; blue connector, 15-pin |
HDMI vs. DisplayPort
| Feature | HDMI | DisplayPort |
|---|---|---|
| Primary Market | Consumer electronics (TVs, consoles) | Computer monitors |
| Daisy-Chaining | No | Yes (MST — Multi-Stream Transport) |
| Max Cable Length | 15m (passive) | 3m (passive), longer with active cables |
| Locking Mechanism | Friction only | Latch (on most connectors) |
| Licensing | Requires royalty payment | Royalty-free |
USB Connectors
| Type | Shape | Speed | Notes |
|---|---|---|---|
| USB-A | Rectangular (flat) | Varies by version | Most common PC connector |
| USB-B | Square | Varies by version | Printers, external drives |
| Mini-USB | Small trapezoidal | USB 2.0 (480 Mbps) | Legacy cameras, controllers |
| Micro-USB | Small flat | USB 2.0/3.0 | Legacy phones, devices |
| USB-C | Oval, reversible | Up to 40 Gbps (USB4) | Modern universal connector |
USB Speed Standards
| Standard | Marketing Name | Max Speed | Connector |
|---|---|---|---|
| USB 2.0 | Hi-Speed | 480 Mbps | A, B, Mini, Micro |
| USB 3.0/3.2 Gen 1 | SuperSpeed | 5 Gbps | A (blue), B, Micro-B, C |
| USB 3.1/3.2 Gen 2 | SuperSpeed+ | 10 Gbps | A, C |
| USB 3.2 Gen 2x2 | SuperSpeed 20Gbps | 20 Gbps | C only |
| USB4 | USB4 | 40 Gbps | C only |
Exam Tip: USB 3.0 ports and connectors are identified by their blue color on USB-A connectors.
Test Your Knowledge
What is the maximum cable distance for Cat 6a Ethernet at 10 Gbps?
A
B
C
D
Test Your Knowledge
What color jacket identifies a single-mode fiber optic cable?
A
B
C
D
Test Your Knowledge
Which video connector supports daisy-chaining multiple monitors from a single output?
A
B
C
D
Test Your KnowledgeMatching
Match each fiber optic connector to its description:
Match each item on the left with the correct item on the right
1
SC
2
LC
3
ST
4
RJ-45