Networking Fundamentals

Lesson Introduction

Computer networks are complex systems incorporating multiple functions, standards, and proprietary technologies. The Open Systems Interconnection

(OSI) model is used to try to simplify some of this complexity. It divides network technologies into seven functional layers. This makes it easier to separate and focus on individual concepts and technologies while retaining an understanding of relationships to the functions of technologies placed in other layers.

This lesson uses the OSI model to give you an overview of the technologies you will study in the rest of the course. You will compare the functions of these layers in the OSI model and apply those concepts to the installation and configuration of a small office/home office network.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Compare and contrast OSI model layers.
• Configure SOHO networks.

Lesson Introduction

At the physical layer, networks are made from different cabling types and their connectors and transceivers. These establish direct links between nodes in a local segment. At the data link layer, nodes in these segments are given a standard means of exchanging data as frames.

Since these two layers are closely related, networking products often define standards for physical and data link layers. While plenty of products have been used in the past, many cabled networks are now based on Ethernet standards. Understanding the options and specifications for Ethernet is essential to building and supporting networks of all sizes.

In this topic, you will summarize standards for deploying Ethernet over copper and fiber optic media types and identify the tools and techniques required to deploy Ethernet cabling.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Summarize Ethernet standards
• Summarize copper cabling types.
• Summarize fiber optic cabling types.
• Deploy Ethernet cabling.

Lesson Introduction

Cabling establishes the links between nodes on the network, but each node also requires a network interface. Only a few networks are established by directly connecting each end system to every other local system. Cabling and support costs are reduced by using intermediate systems to create local networks. These intermediate systems are deployed as network appliances such as hubs, bridges, and switches. Installing and configuring these devices will be a regular task for you during your career in network administration.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Deploy networking devices.
• Explain network interfaces.
• Deploy common Ethernet switching features.

Lesson Introduction

Whether you are dealing with support cases or validating an installation or configuration, problem-solving is a critical competency for all network technicians. Effective problem-solving requires a mixture of technical knowledge, soft skills, intuition, and the discipline to apply a structured approach.

In this lesson, you will explain the steps in CompTIA’s Network+ troubleshooting methodology and apply these steps to solving typical cable and connectivity issues.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Explain network troubleshooting methodology.
• Troubleshoot common cable connectivity issues.

Lesson Introduction

The physical and data link layers covered in the previous lessons establish local connections between nodes. At the network layer (layer 3), these individual networks can be connected to a network of networks or internetwork.

In this lesson, you will identify the addressing and data delivery methods of the Internet Protocol (IP). IP is at the heart of most modern networks and, consequently, one of the most critical topic areas for a network professional to understand and apply.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Explain IPv4 addressing schemes.
• Explain IPv4 forwarding.
• Configure IP networks and subnets

Lesson Introduction

IP is implemented on network hosts using various configuration interfaces and tools. You must be confident about selecting an appropriate tool to complete a support or troubleshooting task.

This lesson also introduces IPv6 addressing concepts and highlights some key differences between IPv6 and IPv4.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Use appropriate tools to test IP configuration.
• Troubleshoot IP networks.
• Explain IPv6 addressing schemes.

Lesson Introduction

Now that you know the basic concepts of IP addressing and forwarding, you can start identifying ways to implement paths between networks. Routers work

at layer 3 to aggregate information about neighboring networks and forward packets along an appropriate path to their final destination.

While configuring routing infrastructure is often a senior job role, you should understand basic concepts and be able to apply them to solve common issues.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Compare and contrast routing concepts.
• Compare and contrast dynamic routing concepts.
• Install and troubleshoot routers.

Lesson Introduction

The cabling, switching, and routing functions of the first three layers in the OSI model can be deployed in many ways to implement networks of varying sizes and with different purposes. Summarizing these network types and topologies and the various network appliance models that support them will help you build networks that meet customer goals for performance and security.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Explain network types and characteristics.
• Explain tiered switching architecture.
• Explain virtual LANs.

Lesson Introduction

Layers 1 through 3 of the OSI model are concerned with addressing and packet forwarding and delivery. This basic connectivity is established to transport application data. In this lesson, you will learn to describe how protocols at layer 4 provision the transport services that network applications depend upon.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Compare and Contrast Transport Protocols
• Use Appropriate Tools to Scan Network Ports

Lesson Introduction

You have identified the Physical, Data Link, Network, and Transport layer technologies and protocols that underpin basic connectivity. The TCP/IP protocol suite also includes application protocols that implement network services.

This lesson focuses on application protocols that perform low-level network operations tasks, such as providing dynamic address or name resolution services. You should understand the network services protocols’ functions and the ports they rely upon to operate.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Explain the Use of Network Addressing Services
• Explain the Use of Name Resolution Services
• Configure DNS Services

Lesson Introduction

Where DHCP and DNS support basic network operations, other application protocols provide platforms for user-level services, such as websites, databases, file/printer sharing, email, and voice/video calling.

You must be able to identify the ports used by these services and their performance and security requirements so that you can assist with product deployments and upgrades and perform basic troubleshooting.

In this lesson, you will identify common network applications and service platforms.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Explain the Use of Web, File/Print, and Database Services
• Explain the Use of Email and Voice Services

Lesson Introduction

So far in this course, you have learned about all the different network media and topologies and the application protocols for building network connectivity and services. In this lesson, you will investigate some tools and management methods to help you determine your network’s baseline and optimize your network’s performance.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Explain the Use of Network Management Services
• Use Event Management to Ensure Network Availability
• Use Performance Metrics to Ensure Network Availability

Lesson Introduction

You have identified the essential components and concepts for deploying and monitoring a network, but a network implementation is not complete without security mechanisms. In this lesson, you will describe basic concepts related to network security. As

a networking professional, it is part of your responsibility to understand these fundamental concepts so that you can support network security controls.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Explain Common Security Concepts
• Explain Authentication Methods

Lesson Introduction

Each day, the number and complexity of threats against systems integrity and data security increases. In response, more and more security controls are available to automate the detection and prevention of these threats. Because you are a networking professional, your organization and users will be looking to you to deploy these security appliances without compromising network availability and performance.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Compare and Contrast Security Appliances
• Troubleshoot Service and Security Issues

Lesson Introduction

Unbounded or wireless media technologies have distinct advantages for businesses over bounded media. They can be easier to install on existing premises and support the device mobility users require from laptop or smartphone-based access to networks. Wireless technology implementations offer various advantages, but you must understand their limitations and security issues to support them in your network environments properly.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Summarize Wireless Standards
• Install Wireless Networks
• Troubleshoot Wireless Networks
• Configure and Troubleshoot Wireless Security

Lesson Introduction

Most local networks require an external connection to the global Internet or within an enterprise WAN. Service provider links typically facilitate these long-distance communications. Supporting WAN and Internet access effectively is an essential competency to learn.

In this lesson, you will identify the characteristics of WAN service provider offers and components of remote access network implementations.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Explain WAN Provider Links
• Compare and Contrast Remote Access Methods

Lesson Introduction

The cabling, switches, routers, security appliances, servers, and clients that make up a local network must all be located within a site. Managing a site so the network is highly available and secure involves creating policies and best practices supported by documentation. This might seem less immediately rewarding than getting a new application or server up and running, but these operational procedures are just as important to well-managed networks.

Site management can also involve the management of unfamiliar technologies, such as physical access controls, embedded systems, and Internet of Things (IoT) devices. As a network technician, you will be expected to know the unique challenges posed by incorporating these systems within sites and networks.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Explain Organizational Documentation and Policies
• Explain Physical Security Methods
• Compare and Contrast Internet of Things Devices

Lesson Introduction

Even with effective management procedures and premises security controls, disasters can overwhelm a site and threaten the core functions that a business must perform. Planning for disasters and designing systems for high availability is critical to supporting these mission-essential functions. As an entry-level technician or administrator, you should be able to explain the importance of these concepts and identify the tools and techniques used to implement them.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Explain Disaster Recovery Concepts
• Explain High Availability Concepts

Lesson Introduction

There are many ways in which networks can be attacked and just as many ways to make networks more secure. You will need a basic understanding of the security risks and security methods and tools to protect your network. In this lesson, you will learn to compare and contrast common types of attacks and to apply network hardening techniques.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Compare and Contrast Types of Attacks
• Apply Network Hardening Techniques

Lesson Introduction

As the Internet becomes more robust and capable of matching the performance of local networks, many services are being moved from on-premises servers to cloud providers. Even where services are kept on-site, datacenters’ different requirements and design principles are essential competencies for network technicians at all levels.

This lesson completes the Network+ course by summarizing the software-driven virtualization, automation, and orchestration functionality that underpins cloud services.

Lesson Objectives/Topics

In this lesson, you will do the following:

• Summarize Cloud Concepts
• Explain Virtualization and Storage Area Network Technologies
• Explain Datacenter Network Architecture