CCNA RnS Article #7 - Ethernet Standards
CCNA RnS Article #7 – Ethernet Standards
Today let’s talk about various Ethernet physical layer
standards. These standards define how data is sent over the physical cabling
and the speed supported by different cables or connectors involved. Some of
the standards define the protocols and the rules that to be followed when
building the Ethernet LAN. Ethernet Standards are defined by IEEE and follow a
naming format. All Physical Ethernet standards start with 802.3.
There are various varieties of links that can be used to
build a network. These links can be built using copper wire (UTP) or Glass
Fiber cable. This is why we have so many standards in place that
define different media (cables) and connectors. These media and connectors
have different link speeds ranging from 10 Mbps to 400 Gig.
In a broader way, the links/cabling can be categorized into
two types – copper wires or glass fiber. UTP cabling allows data transfer over
the electronic circuit via copper wire.
 |
| Fig 1.1- Ethernet Standards |
Fiber optic cable contains long thin strands of fiberglass. The attached devices send light over the glass fiber in the cable. Fiber Cables support larger distances between devices compared to UTP cables. Fiber optic cables are an expensive option to build a network.
A network engineer needs to understand these standards to
choose the right products when building up a new LAN/WAN setup. As already stated,
IEEE uses a specific naming convention to understand whether the standard is a physical
layer Ethernet standard – all these standards start with 802.3 followed by a suffix.
There are some letters in the standards/specifications that give
a clue whether this standard is for copper or fiber. For example, all UTP
standards have “T” and fiber standards have “X” in the name. Let’s understand
it with some examples –
|
Speed |
Common
Name |
IEEE
Common Name |
IEEE
Formal Name |
Cable
type |
Length |
|
10Mbps |
Ethernet |
10BASE-T |
802.3 |
Copper |
100 m |
|
100Mbps |
Fast Ethernet
|
100BASE-T |
802.3u |
Copper |
100 m |
|
1000Mbps |
Gigabit
Ethernet |
1000BASE-LX |
802.3z |
Fiber |
5000 m |
|
1000Mbps |
Gigabit
Ethernet |
1000BASE-T |
802.3ab |
Copper |
100 m |
|
10Gbps |
10 Gig
Ethernet |
10GBASE-T |
802.3an |
Copper |
100 m |
