Fundamentals of Ethernet (IEEE 802.3 and DIX)

Ethernet is the popular LAN technology to create a home network. IEEE 802.3 defines the technical aspects of an Ethernet.

Ethernet is a LAN media type that uses CSMA/CD to send information and functions at the Data Link Layer of the OSI Reference Model.

Ethernet media types having different physical topologies but support a single logical topology: bus topology. I will explain the different kinds of topologies supported by Ethernet later.

We can design an Ethernet LAN with different shapes (using different physical topologies), but the communication happens in Bus topology only.

You must understand one point. Ethernet supports multiple physical topologies. However, the communication happens in bus topology only.

1. Bus topology
   
   
2. Star Topology
   
   
3. Point to Point

It has two versions right now. One is the DIX version, and the second is the IEEE version. This tutorial explains various topologies and versions of Ethernet.

Let us check the two different Ethernet standards.

1. DIX Version

   DIX Ethernet or Ethernet 2 is popular. This version does not split the Data Link layer into two. Ethernet 2 has a frame value of more than 1500. This standard is designed by the combined work of three companies.

   Those companies are DEC, Intel, and Xerox. This standard gets the name DIX by taking the first letter from the names of these three companies.

2. IEEE Version

   This version of Ethernet comes under IEEE 802.2 and 802.3. Here, the data link layer has two divisions. They are LLC and MAC. To read more about it, visit the links below.

   
   
   1. LLC (Logical Link Control) IEEE 802.2
      
      
   2. MAC Sublayer Defined in IEEE 802.3
   
   

   We can easily distinguish between an IEEE ethernet and a DIX Ethernet. The Frame value of IEEE802.3 is less than 1500. It is the difference between IEEE and DIX versions.

To read more about the devices and protocols work in standard, visit the link below.