Cabling, Connectors and Standards
Distance and speed are what these questions turn on. A scenario gives you a run length and a required speed, and the answer is whichever standard covers both.
Cabling, Connectors and Standards · firsttry.app/cheatsheets/cabling-and-connectors · original reference written from published exam objectives. Not affiliated with any certification body.
Copper Ethernet standards
| Standard | Speed | Cable | Max distance |
|---|---|---|---|
| 10BASE-T | 10 Mbps | Cat 3 or better | 100 m |
| 100BASE-TX | 100 Mbps | Cat 5 | 100 m |
| 1000BASE-T | 1 Gbps | Cat 5e | 100 m |
| 2.5GBASE-T | 2.5 Gbps | Cat 5e | 100 m |
| 5GBASE-T | 5 Gbps | Cat 6 | 100 m |
| 10GBASE-T | 10 Gbps | Cat 6 | 55 m |
| 10GBASE-T | 10 Gbps | Cat 6a or Cat 7 | 100 m |
| 40GBASE-T | 40 Gbps | Cat 8 | 30 m |
Fibre standards
| Standard | Speed | Fibre type | Max distance |
|---|---|---|---|
| 100BASE-FX | 100 Mbps | Multimode | 2 km |
| 1000BASE-SX | 1 Gbps | Multimode | 550 m |
| 1000BASE-LX | 1 Gbps | Single-mode | 5 km |
| 10GBASE-SR | 10 Gbps | Multimode | 400 m |
| 10GBASE-LR | 10 Gbps | Single-mode | 10 km |
| 10GBASE-ER | 10 Gbps | Single-mode | 40 km |
Connectors
| Connector | Used with |
|---|---|
| RJ45 | Ethernet over twisted pair, 8 pins |
| RJ11 | Telephone and DSL, 4 or 6 pins |
| LC | Fibre, small form factor, duplex |
| SC | Fibre, square push-pull |
| ST | Fibre, round bayonet |
| MPO / MTP | Fibre, multi-strand for 40G and 100G |
| F-type | Coaxial, cable modem and TV |
| BNC | Coaxial, legacy and video |
| SFP / SFP+ / QSFP | Transceiver cages, 1G / 10G / 40G+ |
T568A and T568B pinout
| Pin | T568A | T568B |
|---|---|---|
| 1 | White/Green | White/Orange |
| 2 | Green | Orange |
| 3 | White/Orange | White/Green |
| 4 | Blue | Blue |
| 5 | White/Blue | White/Blue |
| 6 | Orange | Green |
| 7 | White/Brown | White/Brown |
| 8 | Brown | Brown |
Exams covered
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