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Module 5: Switches / Overview

Module 5: Switches / 
Overview

  The task to design a network can be a challenge as it involves more than just a connection of two computers. A network requires many features in order to be reliable, manageable, and scalable. To design reliable, manageable, and scalable networks, network designers must realize that each of the major components of a network has distinct design requirements.
Network design has become more difficult despite improvements in equipment performance and media capabilities. The use of multiple media types and LANs that interconnect with other networks add to the complexity of the network environment. Good network designs improve performance and also reduce the difficulties associated with network growth and evolution.
A LAN spans a single room, a building, or a set of buildings that are close together. A group of buildings that are located close to each other and belong to a single organization are referred to as a campus. The following aspects of the network need to be identified before a large LAN is designed:
  • An access layer that connects end users to the LAN
  • A distribution layer that provides policy-based connectivity between end-user LANs
  • A core layer that provides the fastest connection between the distribution points
Each of these LAN design layers require switches that are best suited for the specific tasks. The features, functions, and technical specifications for each switch vary based on the LAN design layer for which the switch is intended. For the best network performance, it is important to understand the role of each layer and then choose the switch that best suits the layer requirements.
This module covers some of the objectives for the CCNA 640-801 and ICND 640-811 exams.  
Students who complete this module should be able to perform the following tasks:
  • Describe the four major goals of LAN design
  • List the key considerations in LAN design
  • Understand the steps in systematic LAN design
  • Understand the design issues associated with Layers 1 through 3 LAN structure, or topology
  • Describe the three-layer design model
  • Identify the functions of each layer of the three-layer model
  • List Cisco access layer switches and their features
  • List Cisco distribution layer switches and their features
List Cisco core layer switches and their features

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