Ethernet Standards
[!NOTE] This module explores the core principles of Ethernet Standards, deriving solutions from first principles and hardware constraints to build world-class, production-ready expertise.
1. What is Ethernet?
Ethernet is a family of wired computer networking technologies commonly used in local area networks (LANs). It is standardized as IEEE 802.3.
2. Physical Media
Data travels over different physical mediums depending on distance and speed requirements.
Twisted Pair (Copper)
Eight thin wires twisted into pairs to cancel out electromagnetic interference (Crosstalk).
- Cat5e: Up to 1Gbps (100 meters).
- Cat6a: Up to 10Gbps (100 meters).
- Connector: RJ-45.
Fiber Optic
Uses light pulses to send data through glass or plastic cores.
- Single-mode: Long distance (Kilometers).
- Multi-mode: Short distance (Inside Data Centers).
- Pros: Immense bandwidth, zero electromagnetic interference.
3. Speed Evolution
| Standard | Name | Speed | Medium |
|---|---|---|---|
| 10BaseT | Ethernet | 10 Mbps | Cat3/5 |
| 100BaseTX | Fast Ethernet | 100 Mbps | Cat5 |
| 1000BaseT | Gigabit Ethernet | 1 Gbps | Cat5e/6 |
| 10GBASE-T | 10 GigE | 10 Gbps | Cat6a |
4. Interactive: Cable Picker
Choose the right cable for the distance.
Target: Connect two buildings 500 meters apart.
5. Topologies Revisited
Modern Ethernet uses a Physical Star (all cables go to a switch) but acts as a Logical Bus (everyone is part of the same broadcast domain).