Local Area Network (LAN) - CCNA Study Material

Local Area Network (LAN) is a collection of connected devices in a small area. A home network (one router connected to computers and smartphones) is an example of a LAN.

LAN helps to communicate between devices in a smaller area and improve the efficiency of working in an office.

So, how do we decide if a network is a LAN? In a LAN, all devices are connected and can share data. A LAN covers a small area (such as an office building, home, etc.).

Let us consider common topologies used in Local Area Networks because it is in the CCNA Exam Syllabus.

In Physical Topology, you can see how devices in a LAN are connected, but in Logical Topology, we can see how these devices communicate.

1. Point to Point

   If we connect two devices without interference from other devices, that is a Point-To-Point physical topology. In this LAN topology, these two devices can communicate without extra support.

   
   

   Wireless Bridge is an example of Wireless Point-to-Point Topology.

   
   

2. Bus Topology

   You can say it is an extension of Point-to-Point topology. In Bus topology, we connect all devices in LAN in a single connection.

   
   

   Ethernet uses Bus topology.

   
   

3. Ring

   If a Local Area Network has Ring Topology, all devices are in a ring form. It means PC 1 connects to PC 2. PC 2 connects to PC 3, and the last device connects to PC 1. So, it forms a ring structure.

   
   

   FDDI uses a ring topology.

   
   

4. Star Topology

   In start topology, all devices in a LAN have a connection to the central device. An example is all the computers connected to a Switch.

1. Bus Topology

   Ethernet is an example of a LAN technology using a logical bus structure to communicate. To learn more about Ethernet, visit the link below.

   Fundamentals of Ethernet
   
   
   

2. Ring Topology

   Token Ring is a good example that uses ring logical topology to communicate computers connected to the network.

   
   

1. Twisted-pair wire
   
   
2. Coaxial cables
   
   
3. Fiber optic cables