What is Ethernet?

Whether you're new to the field of networking, studying for your CompTIA Network+ Certification, an enthusiast, or a seasoned network professional doing a refresher course, you'll encounter Ethernet. In this section, we will help you to better understand the characteristics and the responsibilities of Ethernet in a network.

To put it simply, Ethernet is a technology used in all modern day local area networks (LANs). It is used to help with the logical communication of network devices over a wired network infrastructure with the use of various protocols. As mentioned previously, a protocol is a set of rules of procedures which are used to govern how information or data is passed within a system, along a network.

The Institute of Electrical and Electronics Engineers (IEEE) has created standards for Ethernet, known as IEEE 802.2 and IEEE 802.3, which define how Ethernet can be used within a wired network. Ethernet operates at both the Data Link Layer and the Physical Layer of the OSI reference model:

IEEE 802.2 and IEEE 802.3 define how Protocol Data Units (PDUs), such as frames and bits, are handled by both the Data Link Layers and Physical Layer as they are either passed down the protocol suite onto the network (sending) or vice versa (receiving).

Ethernet also defines and supports data transfer rates on networking devices interfaces, as follows:

• 10 MBps—Ethernet
• 100 MBps—Fast Ethernet
• 1000 MBps—Gigabit Ethernet
• 10,000 MBps—10 GB Ethernet