Ethernet cables are classified based on their transmission speeds, shielding, and ability to reduce crosstalk and interference. Below is a technical comparison of CAT5, CAT5e, CAT6, and CAT7, detailing their speeds, supported distances, and specifications.
1. CAT5 (Category 5)
- Max Speed:
- 100 Mbps (up to 100 meters)
- 1 Gbps (up to ~20 meters under ideal conditions)
- Max Frequency: 100 MHz
- Max Distance at Full Speed:
- 100 Mbps: 100 meters (328 feet)
- 1 Gbps: ~20 meters (65 feet)
- Shielding: Mostly Unshielded (UTP); some older STP variants exist
- Bandwidth Type: Half-duplex or full-duplex
- Typical Use Case: Legacy networks, basic data and voice applications
Technical Notes
- Uses two twisted pairs (4 wires total) for Fast Ethernet (100 Mbps).
- 1 Gbps speeds are possible but only at short distances (~20 meters) and with high-quality cables.
- High susceptibility to crosstalk and electromagnetic interference (EMI) compared to later versions.
- Generally considered obsolete for modern networking needs.
2. CAT5e (Category 5 Enhanced)
- Max Speed: 1 Gbps (Gigabit Ethernet)
- Max Frequency: 100 MHz
- Max Distance at Full Speed: 100 meters (328 feet)
- Shielding: Mostly Unshielded (UTP); shielded (STP) variants exist
- Bandwidth Type: Full-duplex
- Typical Use Case: Standard home and office networking
Technical Notes
- Introduced tighter twists and improved insulation to reduce crosstalk and interference.
- Fully supports 1 Gbps over the full 100-meter cable length.
- Backward compatible with CAT5.
- Supports Power over Ethernet (PoE) without additional modifications.
3. CAT6 (Category 6)
- Max Speed:
- 1 Gbps (up to 100 meters)
- 10 Gbps (up to 55 meters)
- Max Frequency: 250 MHz
- Max Distance at Full Speed:
- 1 Gbps: 100 meters (328 feet)
- 10 Gbps: 55 meters (180 feet)
- Shielding: Available in both UTP (unshielded) and STP (shielded)
- Bandwidth Type: Full-duplex
- Typical Use Case: High-speed networking, enterprise applications, data centers
Technical Notes
- Uses thicker copper conductors and tighter twists to minimize crosstalk.
- Backward compatible with CAT5 and CAT5e networks.
- Supports 10 Gbps speeds, but only for distances up to 55 meters.
- Improved Alien Crosstalk (AXT) mitigation, especially in shielded (STP) versions.
4. CAT7 (Category 7)
- Max Speed: 10 Gbps
- Max Frequency: 600 MHz
- Max Distance at Full Speed: 100 meters (328 feet)
- Shielding: Fully shielded (S/FTP – Shielded Foiled Twisted Pair)
- Bandwidth Type: Full-duplex
- Typical Use Case: High-end data centers, industrial networks, future-proof infrastructure
Technical Notes
- Features individual shielding for each twisted pair plus an overall shield, greatly reducing crosstalk and EMI.
- Fully supports 10 Gbps speeds up to 100 meters, making it superior to CAT6 in long-distance high-speed networking.
- Not an officially recognized TIA/EIA standard, but specified under ISO/IEC 11801.
Summary Table: Performance Comparison
| Category | Max Speed | Max Distance at Full Speed | Max Frequency | Shielding | Use Case |
|---|---|---|---|---|---|
| CAT5 | 100 Mbps (100m), 1 Gbps (~20m) | 100m (100 Mbps), ~20m (1 Gbps) | 100 MHz | UTP/STP | Legacy networks, voice applications |
| CAT5e | 1 Gbps | 100 meters | 100 MHz | UTP (STP available) | Standard home/office networking |
| CAT6 | 1 Gbps (100m), 10 Gbps (55m) | 100m (1 Gbps), 55m (10 Gbps) | 250 MHz | UTP/STP | High-speed office networks, data centers |
| CAT7 | 10 Gbps | 100 meters | 600 MHz | S/FTP (fully shielded) | Industrial applications, high-end data centers |
Final Thoughts
- CAT5 is outdated and only viable for basic networking or short-range 1 Gbps use.
- CAT5e remains the most cost-effective choice for Gigabit Ethernet applications.
- CAT6 offers better performance and some 10 Gbps capability but has distance limitations.
- CAT7 is a high-end option, fully shielded and ideal for environments requiring maximum speed and minimal interference.