Computer Networking Fundamentals - IT Network Essentials

Understanding the OSI (Open Systems Interconnection) model is important because it provides a structured framework for how data moves through a network, from one device to another. By breaking down communication into seven distinct layers, from physical hardware to application-level interactions, it helps IT professionals and students diagnose network issues, design efficient systems, and understand how different technologies interact.

Understanding the TCP/IP model is important because it explains how data is transmitted across networks and the internet. It is the foundation of modern networking, organizing communication into four key layers that handle everything from hardware connections to software applications. By learning the TCP/IP model, professionals can better troubleshoot network problems, design efficient communication systems, and understand how devices exchange information in real-world scenarios.

Cisco’s Three Layer Hierarchical Model provides a clear and scalable structure for building efficient and manageable enterprise networks. The model divides network design into three layers: Core, Distribution, and Access. Each layer has a specific role that simplifies network management, improves performance, enhances security, and makes scaling easier.

Understanding the difference between Peer to Peer and Client Server networks is important because it helps determine the right network setup for specific needs. In a Peer to Peer network, devices share resources directly with each other without a central server, making it simple and cost-effective for small setups. In contrast, a Client Server network uses dedicated servers to manage resources and security, which is more efficient and scalable for larger or more structured environments. Knowing how these models differ supports better planning, performance, and security in network design.

Understanding the difference between LANs and WANs is important because it helps in designing networks that suit the size and scope of an organization’s needs. A LAN, or Local Area Network, connects devices within a limited area like a home, office, or school, offering high speed and low latency. A WAN, or Wide Area Network, spans large geographic areas and connects multiple LANs, often using leased lines or the internet. Knowing how each works helps ensure the right equipment, speed, and security measures are used for effective and reliable communication.

Understanding DNS, or Domain Name System, is important because it allows users to access websites and services using easy-to-remember names instead of numerical IP addresses. DNS works like an internet phonebook, translating domain names like example.com into IP addresses that computers use to locate each other. It plays a critical role in every internet request, affecting speed, reliability, and security.

Understanding DHCP, or Dynamic Host Configuration Protocol, is important because it simplifies and automates the process of assigning IP addresses and network settings to devices on a network. Without DHCP, each device would need to be manually configured, which is time-consuming and prone to errors. DHCP ensures that devices receive the correct IP address, gateway, and DNS information automatically, allowing them to communicate on the network with minimal setup.

Understanding network adapters is important because they serve as the essential hardware components that connect computers and devices to a network. Knowing how network adapters work helps in troubleshooting connectivity issues, optimizing network performance, and ensuring compatibility with different network types.

Wireless access points enable devices to connect to a wireless network, extending the range and improving network coverage. Understanding how access points function helps in designing and managing reliable Wi-Fi networks, troubleshooting connection problems, and ensuring strong signal strength.

Knowing about firewalls, VPNs, and IDS-IPS systems is important because they are key tools for protecting networks and data from unauthorized access and cyber threats. Firewalls control incoming and outgoing traffic to block malicious activity, VPNs create secure connections over public networks to protect privacy, and IDS-IPS systems monitor network traffic to detect and prevent attacks.

Network firewalls act as a barrier that protects your network from unauthorized access and cyber attacks. Firewalls monitor and control the flow of data between trusted and untrusted networks, helping to block harmful traffic while allowing legitimate communication. Understanding how firewalls work is essential for securing networks, preventing data breaches, and maintaining the integrity of computer systems in both personal and professional settings.

Knowing about switches and hubs is important because they are fundamental devices that connect multiple computers within a network. Switches intelligently direct data to the correct device, improving network efficiency and reducing collisions, while hubs simply broadcast data to all connected devices. Understanding the differences between them helps in designing and managing networks that are faster, more secure, and better suited to specific needs.

Routers connect different networks and direct data between them, enabling devices to communicate both within a local network and with the internet. Routers manage traffic efficiently, assign IP addresses, and often include security features like firewalls. Understanding how routers work is essential for setting up reliable, secure networks and troubleshooting connectivity issues.

Ethernet cables are the physical connections that link devices in a wired network, allowing data to travel quickly and reliably between computers, routers, and switches. Understanding the basics of Ethernet cables helps in choosing the right type for different network speeds and distances, ensuring stable and efficient communication.

Ethernet cable standards and speeds define how fast and efficiently data can be transmitted over a wired network. Different standards support varying speeds and cable types, which impact network performance and compatibility. Understanding these standards helps in selecting the appropriate cables and equipment to meet the needs of a specific network, ensuring optimal speed and reliability.

Fiber optic cables use light to transmit data over long distances at very high speeds with minimal signal loss. They offer greater bandwidth and are less susceptible to interference compared to traditional copper cables. Understanding fiber optic cables is important for designing and maintaining high-performance networks, especially in environments that require fast and reliable data transmission.

Coaxial cables are used to transmit data, video, and voice signals through a single copper conductor surrounded by insulation and shielding. They provide reliable connections with good resistance to interference, making them common in cable television and internet networks.

Network cable tools are devices used to install, test, and maintain network cables, ensuring proper connections and functionality. These tools help identify wiring issues, verify signal quality, and make precise cable terminations. Understanding how to use network cable tools is essential for building reliable networks and troubleshooting connectivity problems efficiently.

Wireless networks use radio signals to connect devices without physical cables, allowing for greater mobility and convenience. Understanding Wi-Fi basics helps in setting up secure and efficient wireless connections, managing signal strength, and troubleshooting common issues. This knowledge is important for ensuring reliable internet access in homes, offices, and public spaces.

Wireless frequencies and standards determine how wireless devices communicate, including the range, speed, and interference levels of the connection. Different frequency bands and standards support various Wi-Fi technologies, affecting network performance and compatibility with devices. Understanding these concepts is important for optimizing wireless networks and ensuring reliable and fast connections.

Wireless frequencies and standards determine how wireless devices communicate and at what speeds they can transfer data. Different frequencies offer varying ranges and levels of interference, while standards set the rules for compatibility and performance. Understanding wireless frequencies and standards is important for optimizing network coverage, ensuring device compatibility, and maintaining a stable and fast wireless connection.

Here is the command to view your saved wireless connections.

netsh wlan show profiles

Here is the command to delete a wireless connection. Be sure to replace ProfileName with the name of the SSID you want to remove.

netsh wlan delete profile ProfileName

Here is the location of the saved wireless profiles.

C:\ProgramData\Microsoft\Wlansvc\Profiles\Interfaces

If you somehow forgot your Wi-Fi password and want to get it back rather than reconfigure your router, here are some ways to do it.

Here are the commands from the video.

netsh wlan show profile

netsh wlan show profile "your SSID" key=clear

Windows makes it easy to get other users on your wireless network without needing to give them your Wi-Fi password.

Since wireless networks are broadcast though the airwaves, it makes it easier for people or devices that you might not want on your network to gain access. Being able to see what types of devices are on your Wi-Fi network can help you keep things more secure.

IP addressing fundamentals explain how devices on a network are assigned unique numerical identifiers that allow them to communicate with each other. These addresses help route data correctly between devices on local networks and across the internet. Understanding IP addressing is crucial for configuring networks, managing devices, and ensuring accurate and secure data transmission.

IPv4 and IPv6 are two versions of internet protocol that define how devices identify and communicate with each other on a network. IPv4 uses a 32-bit address system, which limits the number of unique addresses, while IPv6 uses a 128-bit system to provide a much larger address space. Understanding the differences between IPv4 and IPv6 is important for managing network addressing, ensuring compatibility, and preparing for future internet growth.

If you prefer to do things via the command line, you can easily configure IP addresses using this method.

Here is the command to set an IPv4 IP address.

netsh interface ipv4 set address name="Ethernet" static 192.168.1.100 255.255.255.0 192.168.1.1

Here is the command to set an IPv6 IP address.

netsh interface ipv6 set address name="Ethernet" static 2001:db8::100

Setting static IP addresses in Windows is a fairly simple task, but there are other configuration options that you have available to really customize your connection settings.

Network ports and protocols are essential for organizing and managing how data is transmitted between devices on a network. Ports act as communication endpoints that allow multiple services to run simultaneously, while protocols define the rules for data exchange. Understanding ports and protocols helps in configuring networks, securing communications, and troubleshooting connectivity issues.

Network ports are virtual communication endpoints that allow devices and applications to send and receive data over a network. Each port is identified by a number and helps direct traffic to the correct service or application. Understanding network ports is important for managing network security, troubleshooting connection issues, and configuring firewalls and routers effectively.

Network protocols are sets of rules and standards that govern how devices communicate and exchange data over a network. They ensure that information is transmitted accurately and efficiently between different systems. Understanding network protocols is essential for configuring, troubleshooting, and securing network communications in any environment.

Cellular data networks allow mobile devices to connect to the internet and communicate wirelessly over wide areas using cellular towers. These networks use different technologies and frequency bands to provide coverage and data speeds.

Ethernet frames are packets of data formatted for transmission over a wired network. They contain important information such as source and destination addresses, error-checking data, and the actual payload. Understanding how Ethernet frames work helps in troubleshooting network communication issues and ensures data is sent and received accurately across devices.

Cable and fiber optic internet are two common types of high-speed broadband connections. Cable internet uses coaxial cables to deliver fast data speeds, while fiber optic internet uses light signals through fiber strands for even faster and more reliable performance.

Satellite technologies enable communication by transmitting signals between Earth and satellites orbiting in space. They provide internet, television, and phone services in remote or hard-to-reach areas where traditional networks may not be available.

There are various network command you can use to view, configure, and troubleshoot network settings and connections through the command line. These commands help diagnose issues, manage IP addresses, test connectivity, and gather important network information quickly.

NTFS permissions control access to files and folders on Windows systems by specifying which users or groups can read, write, or modify data. They provide a detailed and secure way to manage who can interact with resources on a computer or network. Understanding NTFS permissions is important for protecting sensitive information and ensuring that only authorized users have the appropriate level of access.

Share permissions and NTFS permissions control access to files and folders on a network but work in different ways. Share permissions apply when accessing resources over the network, while NTFS permissions control access both locally and remotely on the file system level.

Changing folder permissions using the command line allows users to quickly modify access rights for files and folders without navigating through graphical menus. This method is efficient for managing permissions on multiple folders or remote systems.

Setting up shared folders on a local network allows multiple users to access and collaborate on files easily. This process involves configuring folder permissions and network settings to control who can view or edit the shared content.

Accessing shared folders over the network allows multiple users to easily share and collaborate on files without needing to transfer them individually. It enables efficient file management and resource sharing within homes or organizations.

Mapping network drives allows users to create a shortcut to shared folders or drives on another computer within a network, making access easier and more convenient. This process helps streamline file sharing and collaboration by providing quick access to remote resources as if they were stored locally.

Sharing printers for network access allows multiple users to print documents from different devices without needing a direct connection to the printer. This setup improves convenience and reduces costs by eliminating the need for multiple printers.

Changing your network connection names in Windows helps you easily identify and manage different networks you connect to. This can be especially useful when working with multiple connections, such as home, work, or public networks.

Here is the registry key you will need to edit from the video.

Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\NetworkList\Profiles

Connecting to administrative shares on a Windows 11 networked computer allows authorized users to access system folders remotely for management and troubleshooting. This process requires proper permissions and knowledge of network paths to ensure secure and successful connections.

If you are having trouble connecting to ad administrative share on a remote Windows 11 computer and are getting a message such as "Windows cannot access (share name)" telling you that you do not have permission, then you are not alone. When it comes to networking, Windows 11 is more locked down that Windows 10 and it takes a bit more to get things working.

Here is the registry information from the video.

Navigate to

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System

Create a new DWORD value named LocalAccountTokenFilterPolicy and set its value to 1.

Reboot the computer

System virtualization allows multiple virtual machines to run on a single physical computer, enabling better resource use and isolation between different operating systems or applications. It helps in testing, development, and efficient server management by creating flexible and scalable environments. Understanding system virtualization is important for optimizing hardware, improving security, and simplifying IT operations.

Enterprise level virtualization allows organizations to create multiple virtual machines on a single physical server, improving resource utilization and flexibility. It enables easier management, faster deployment, and better scalability of IT infrastructure.

Desktop virtualization allows users to run multiple desktop environments on a single physical machine such as your Windows 11 desktop. There are many virtualization platforms you can use such as VMware Workstation, VirtualBox and Hyper-V.

Cloud storage allows users to save and access data over the internet instead of on local devices. It provides scalability, flexibility, and remote access to files from anywhere with an internet connection.

Cloud providers for businesses offer remote computing resources and services such as storage, software, and processing power over the internet. They allow companies to scale their operations, reduce infrastructure costs, and improve accessibility and collaboration.

Home and small business cloud services provide online platforms for storing data, running applications, and managing resources without needing extensive local hardware. These services offer flexibility, scalability, and remote access, making it easier to collaborate and protect important information.