Ethernet facts for kids

Ethernet is a common way to connect computers and other devices together in a local area network (LAN). Think of a LAN as a small network, like the one in your home or school. Ethernet has been the most popular way to link computers in these networks since the 1990s.

The main idea behind Ethernet is simple: many computers can share the same connection and send data whenever they need to. This makes it fairly easy to set up.

What happens if two computers try to send data at the exact same time? It's like two people trying to talk at once – a "collision" happens, and the data gets mixed up. When this occurs, both computers stop sending data. They then wait a short, random amount of time before trying again. A special set of rules, called Carrier sense multiple access with collision detection (CSMA/CD), helps manage these situations so data can get through.

What are Ethernet Cables?

Ethernet uses different types of cables. Today, most Ethernet cables look like slightly thicker telephone cords. They connect your computer's network interface card (NIC) to a central box called an hub or an switch. These cables are often known as 10BaseT, 100BaseT, or 1000BaseT.

Here are some of the cable types that have been used:

• Older Coaxial Cables (10Base2 and 10Base5): These were some of the first Ethernet cables. They were similar to TV cables but thinner. Each computer had a special "T" connector, or sometimes a "vampire tap," to join the network. They could send data at 10 million bits per second (10 MBit/second). These types became rare in the 21st century.
• Twisted Pair Cables (10BaseT, 100BaseT, 1000BaseT): These are the most common cables today. They look like thick phone cables but have eight copper wires inside, twisted together. They connect each computer directly to a hub or switch.
  • 10BaseT supported speeds of 10 MBit/second.
  • 100BaseT can go much faster, up to 100 MBit/second.
  • 1000BaseT is even faster, reaching 1 Gigabit (1000 MBit) per second.

The cables used for 10BaseT, 100BaseT, and 1000BaseT often look the same. They are usually made of "unshielded twisted pair" (UTP) wires, like Category 5 (Cat5) or 5e. Sometimes, "shielded twisted pair" (STP) cables are used if there's a lot of electrical interference nearby. Newer Category 6 (Cat6) cables work even better for very fast speeds, like 1 Gigabit or 10 Gigabit per second.

What Can You Connect?

You can connect many different devices using Ethernet cables. Besides computers, things like video game consoles can also use the same type of cabling to connect to the internet or other devices. Some computer peripherals, such as printers and certain hard disks, can also be plugged directly into the network using these cables.

How Fast is Ethernet?

Ethernet can operate at many different speeds. When it first started, Ethernet typically ran at 10 million bits per second (10 MBits/second). Today, the most common Ethernet speed is 100 MBits/second.

Many new computers come with a built-in network card that can handle speeds of 1 Gigabit (1000 MBits) per second. There are also standards for even faster speeds, like 10 Gigabit per second.

Good news: faster Ethernet connections can usually talk to slower ones. For example, a 100 MBit connection can usually work with a 10 MBit connection. A 1 GBit connection can typically talk to both 100 MBit and 10 MBit connections.

Images for kids

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  How a local area network using Ethernet might be connected

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  RJ45 Ethernet connector

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  A twisted pair cable with an 8P8C modular connector attached to a laptop computer, used for Ethernet

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  An Ethernet-over-twisted-pair port

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  Accton Etherpocket-SP parallel port Ethernet adapter (circa 1990). This adapter could use both older coaxial (10BASE2) and twisted pair (10BASE-T) cables.

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  An Intel 82574L Gigabit Ethernet NIC, a card that helps your computer connect to a Gigabit Ethernet network.

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  Older Ethernet equipment. This image shows various parts used with early Ethernet cables, including "vampire taps" and different connectors.

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  A 1990s ISA network interface card that supported both coaxial-cable-based 10BASE2 and twisted-pair-based 10BASE-T.

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  Patch cables connecting to two Ethernet switches. Switches help direct network traffic efficiently.

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  A core Ethernet switch, which is a very important switch in a large network.

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  A close-up of the SMSC LAN91C110 chip, a small electronic part used in embedded Ethernet systems.

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  The original Ethernet setup: all computers shared one cable, which could lead to "collisions" when multiple devices tried to send data at the same time.

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  Modern Ethernet setup: each computer connects to its own switch, which helps prevent collisions and makes the network faster.

See also

In Spanish: Ethernet para niños