Basic Networking Concepts | CompTIA Tech+ FC0-U71 | 2.8

In this video, we’re going to break down the basics of networking concepts.  You’re going to learn everything from how networks communicate to the devices and models that make networking possible. 

Basics of Network Communication

To start, let’s discuss the basics of network communication.

At its core, a network is a system of interconnected devices, such as computers, printers, and servers, that communicate with each other.  The purpose of a network is to share data and resources efficiently.

There are two fundamental types of communication in networking:

• Wired Communication:  This uses physical cables like Ethernet to connect devices, providing reliable and fast data transfer.
• Wireless Communication:  Utilizes radio waves to connect devices over a wireless network, such as WiFi.  While convenient, it can be more prone to interference and slower than wired connections.

When devices communicate, data is transferred in the form of packets, which are small chunks of information that travel from the source to the destination.  A key concept to understand here is the protocol, which is a set of rules that governs how data is transmitted across the network.  The most common protocol is TCP/IP (Transmission Control Protocol / Internet Protocol), which ensures data is sent and received accurately.

Think of network communication like sending a letter:  the data packet is the letter itself, the protocol is the postal system rules, and the network is the road on which the letter travels.

Network Identifiers

Now, let’s dive into network identifiers, which help devices find and communicate with each other on a network.  The two main types are IP addresses and MAC addresses.

• IP Address (Internet Protocol Address)
  • An IP address is a unique identifier assigned to each device on a network.
  • There are two versions of IP addresses:
    • IPv4:  This is the most commonly used format, consisting of four numbers separated by periods (e.g., 192.168.1.1).
    • IPv6:  This is the newer format designed to replace IPv4 and accommodate the growing number of devices.  It consists of eight groups of four hexadecimal digits (e.g., 2001:0DB8:85A3:0000:0000:8A2E:0370:7334).
  • An IP address helps route data to the correct destination.
• MAC Address (Media Access Control Address)
  • A MAC address is a hardware identifier that is unique to each network interface card (NIC).
  • It’s a 12-digit hexadecimal number (e.g., 00:1A:2B:3C:4D:5E) that is typically burned into the hardware by the manufacturer.
  • Unlike IP addresses, which can change, MAC addresses are static and serve as a permanent physical address for a device on a network.
• Ports
  • A port is a logical endpoint used for network communication.
  • Different services use different port numbers to identify themselves.  For example, HTTP uses port 80, HTTPS (secure web browsing) uses port 443, FTP (file transfer) uses port 21, and SMTP (email sending) uses port 25.
  • Think of ports as doors that allow specific types of network traffic to enter or leave a device.

Basic Network Services

Now let’s explore some basic network services, which are functions and applications that use networks to provide specific features to users:

• Secure Web Browsing
  • Secure web browsing is conducted using HTTPS (Hypertext Transfer Protocol Secure), which encrypts the data transmitted between the web server and your browser, protecting it from eavesdropping.
  • It’s critical for activities like online shopping, banking, or any web-based service that handles sensitive data.
• File Transfer
  • File transfer services allow the movement of files across networks.
  • FTP (File Transfer Protocol) and SFTP (Secure File Transfer Protocol) are commonly used protocols for transferring files between devices, with SFTP providing an encrypted channel for secure transfers.
• Email Services
  • Email services rely on various protocols for sending, receiving, and storing messages.
  • SMTP (Simple Mail Transfer Protocol) is used to send emails, while IMAP (Internet Message Access Protocol) and POP3 (Post Office Protocol version 3) are used to retrieve emails from a server.

Networking Devices

Let’s move on to networking devices – the hardware that makes network communication possible.

• Modem
  • A modem (modulator-demodulator) converts digital data from a computer into analog signals suitable for a transmission medium, like a phone line or cable system, and vice versa.
  • It connects your home network to your Internet Service Provider (ISP).
• Router
  • A router directs data packets between networks, such as between your home network and the internet.
  • It uses IP addresses to determine the best path for forwarding data to its destination.
  • Routers also provide NAT (Network Address Translation) to allow multiple devices to share a single public IP address.
• Switch
  • A switch connects devices within a local area network (LAN).
  • It uses MAC addresses to forward data to the correct device, enabling efficient communication within a network.
• Access Point (AP)
  • An access point is a device that allows wireless devices to connect to a wired network.
  • It often works in conjunction with a router to expand the reach of a wireless network.
• Firewall
  • A firewall is a security device that monitors and controls incoming and outgoing network traffic based on predefined security rules.
  • Firewalls can be hardware-based or software-based and serve as a barrier between your internal network and the outside world to block malicious traffic.

Networking Models

Next, let’s discuss networking models, which are approaches to organizing devices and services on a network.

• Client / Server Model
  • In a client/server model, one or more servers provide services or resources, and clients request access to these resources.
  • Common services include file storage, web hosting, and email services.
  • For example, when you use a web browser, your computer is the client, and the web server hosting the website is the server.
• Peer-to-Peer (P2P) Model
  • In a peer-to-peer model, every device on the network can act as both a client and a server.
  • This means any device can share resources, such as files or printers, with any other device.
  • P2P is often used for small networks, like home networks, and for file-sharing applications like BitTorrent.

LAN v. WAN

Lastly, let’s look at network types:  Local Area Networks (LAN) and Wide Area Networks (WAN).

• Local Area Network (LAN)
  • A LAN is a network that connects devices within a limited geographic area, like an office building, school, or home.
  • LANs are typically fast and use Ethernet cables or WiFi to connect devices.
• Wide Area Network (WAN)
  • A WAN covers a much larger geographical area, such as a city, country, or even the world.
  • The most well-known example of a WAN is the internet.
  • WANs often use leased telecommunication lines, satellites, or VPNs to connect multiple LANs over large distances.

In short,  a LAN is like a local neighborhood network, while a WAN is more like an interconnected network of many neighborhoods, covering vast areas.

Conclusion

To wrap up, in this video we covered:

• Network Communication Basics:  Understanding how data is transmitted across wired & wireless networks.
• Network Identifiers:  Including IP addresses, MAC addresses, & ports that allow devices to communicate effectively.
• Basic Network Services:  Such as secure web browsing, file transfer, and email.
• Networking Devices:  From modems to routers, switches, access points, and firewalls.
• Networking Models:  Comparing the client/server and peer-to-peer approaches.
• Network Types:  Distinguishing between Local Area Networks (LANs) and Wide Area Networks (WANs).

Understanding these concepts is foundational for the CompTIA Tech+ exam and helps you grasp the essentials of how networks function.