The Fabric of Network: Ethernet

By: Mujtaba Faraz Baig Mirza

OBJECTIVE

Introduction to Ethernet

Evolution of Ethernet

Introduction to CSMA/CD

Methods of Communication

A brief explanation of Ethernet addressing

A view of network cards

Understanding Ethernet cabling

The two types of Ethernet cables

The term Ethernet refers to a family of standards that together define the physical and data-link layers of the worlds most popular type of LAN

Initially the company Xerox created the original Ethernet standard, later on the Institute of Electrical and Electronics Engineers (IEEE) has defined many Ethernet standards since it took over the LAN standardization process in early 1980s

Introduction to Ethernet

Ethernet refers to the bottom two layers of the OSI model i.e. Layer1 & Layer2

At the data link layer Ethernet is further divided into two sub layers:

1) Media access control (MAC) layer

2)Logical Link Control (LLC) layer

Methods of Communication

Unicast : One to one

Broadcast : One to All

Multicast : One to Many

Ethernet Addressing

IEEE calls it as MAC addressing

Each address is 6 bytes long (48 bits) written in hex decimal format with periods separating each set of 4 hex digits

Ex: 0000.0c12.6589

To ensure a unique MAC address , IEEE assigns an unique code to the manufacturer of the Ethernet cards ,this code is known as Organizational unique Identifier (OUI).

The OUI is the first half (24 bits) of the MAC address. The second half is a number that is never assigned by the manufacturer to any other card.

A view of Network Cards

Ethernet CablesTelecommunication Industry Association (TIA) and Electronics Industry

Alliance (EIA)defines standards for UTP cables like color coding on the cable

Two Types of Ethernet Cables

Ethernet Connection Rules