Ethernet and Fiber
| Speed | Common Name | Media | IEEE Standard |
|---|---|---|---|
| 10 Mbps | Ethernet | Copper | 802.3i |
| 100 Mbps | Fast Ethernet | Copper/Fiber | 802.3u |
| 1 Gbps | Gigabit Ethernet | Fiber | 802.3z |
| 1 Gbps | Gigabit Ethernet | Copper | 802.3ab |
| 10 Gbps | 10 Gigabit | Fiber | 802.3ae |
| 10 Gbps | 10 Gigabit | Copper | 802.3an |
Connector Types
Section titled “Connector Types”| Connector | Usage |
|---|---|
| ST | Terminate fiber connections |
| RJ-45 | Terminate four-pair twisted copper cables |
| DB-9 | Terminate point-to-point serial connections |
| BNC | Terminate legacy coaxial cable connections |
| RJ-11 | Terminate legacy plain old telephone system (POTS) connections |
Copper Ethernet Standards (Twisted Pair)
Section titled “Copper Ethernet Standards (Twisted Pair)”These are the most heavily tested standards because they deal with the standard RJ-45 cables you patch into switches.
| IEEE Standard | Common Name | Speed | Minimum Cable Type |
|---|---|---|---|
| 802.3i | 10BASE-T | 10 Mbps | Cat3 |
| 802.3u | 100BASE-TX (Fast Ethernet) | 100 Mbps | Cat5 |
| 802.3ab | 1000BASE-T (Gigabit Ethernet) | 1 Gbps | Cat5e |
| 802.3bz | 2.5GBASE-T / 5GBASE-T (mGig) | 2.5 Gbps / 5 Gbps | Cat5e / Cat6 |
| 802.3an | 10GBASE-T | 10 Gbps | Cat6a |
Fiber Optic Ethernet Standards
Section titled “Fiber Optic Ethernet Standards”While you do not need to memorize every single fiber standard, you need to know the broad categories that differentiate 1 Gbps from 10 Gbps fiber links.
| IEEE Standard | Common Name | Speed | Cable Type |
|---|---|---|---|
| 802.3z | 1000BASE-X | 1 Gbps | Multimode / Singlemode Fiber |
| 802.3ae | 10GBASE-X | 10 Gbps | Multimode / Singlemode Fiber |
Power over Ethernet (PoE) Standards
Section titled “Power over Ethernet (PoE) Standards”Do not skip these. Cisco heavily tests your ability to match the IEEE PoE standard with the maximum wattage it can provide to an end device (like a Lightweight AP or an IP Phone).
| IEEE Standard | PoE Generation Name | Maximum Power per Port | Target Devices |
|---|---|---|---|
| 802.3af | PoE (Type 1) | 15.4 Watts | Basic IP Phones, simple IP cameras |
| 802.3at | PoE+ (Type 2) | 30 Watts | Dual-radio Wireless APs, Video phones |
| 802.3bt | UPoE / PoE++ (Type 3 & 4) | 60 Watts to 90 Watts | High-end APs, PTZ cameras, digital signage |
The “Base” Cheat Sheet Standard The Mnemonic Trick Cable Type 1000Base-SX S is for Short distance. MMF (Multi-Mode Fiber) 1000Base-LX L is for Long distance. SMF (Single-Mode Fiber) 1000Base-ZX Z is for eZtra long distance. SMF (Single-Mode Fiber) 1000Base-CX C is for Copper. Twinax Copper Cable 1000Base-T T is for Twisted Pair. Standard UTP (Cat5/Cat6)