The following is Essential IT terminology every IT administrator should be familiar with. This terminology will be referred to through the course
Key IT Terminology
- Hardware: The physical parts of a computer or server, like the CPU, memory, storage devices, and peripherals such as keyboards and monitors. These are the tangible components you interact with.
- Software: The programs and applications that run on hardware. This includes everything from operating systems (like Windows or Linux) to productivity tools (like Microsoft Office) and specialized applications (like Photoshop).
- Networks: A network is a collection of connected devices that can communicate with each other. Networks range from small local networks (like your home Wi-Fi) to large global networks (like the Internet). In the case of large enterprise networks, it often refers to a single subnet.
- Networking Devices: Equipment that connects computers, servers, or other devices together within a network, enabling them to communicate and share data. Examples of networking devices include routers, switches, wireless access points and firewalls
- Server Types: Servers are specialized computers that provide services to other devices on a network. Common server types include:
- Web Servers: Host websites and serve web pages to users.
- Database Servers: Store, manage, and retrieve data for applications.
- File Servers: Store and share files across a network.
- Application Server: Hosts an applications to end users and handles the logic, processing, and execution of applications
- Mail Server: Sending, receiving, filtering and storage of emails
- Printer Server: Receives print requests from clients and sends them to the appropriate printer. It allows multiple users to share a single printer or group of printers
- Domain Controller: Server that manages user authentication and security policies within a Windows domain
- Terminal Server: Hosts a Windows Desktop for users to log into
- Protocols: These are the rules that govern how data is transmitted over a network. Common protocols include:
- HTTP/HTTPS: Used for transferring web pages.
- FTP: Used for file transfers.
- TCP/IP: The foundational protocol suite for most networks, including the Internet.
- IP Address: A unique identifier for a device on a network. It’s like a phone number for your computer, allowing it to communicate with other devices.
- DNS (Domain Name System): Translates human-readable domain names (like www.example.com) into IP addresses that computers use to identify each other on the network.
- Firewalls: Security systems that monitor and control incoming and outgoing network traffic based on predetermined security rules. Firewalls help protect networks from unauthorized access.
- Virtualization: The creation of virtual versions of physical components, such as servers or storage devices. Virtualization allows multiple virtual servers to run on a single physical server, making IT environments more flexible and efficient.
- Cloud Computing: The delivery of computing services (like servers, storage, databases, networking, software) over the internet. It allows for on-demand access to resources without needing to own and manage physical hardware.
Basic System Architectures & Concepts
System architecture is like the blueprint for how IT systems are built and work together. Here’s a quick look:
- Client-Server Architecture: A model where multiple devices (clients) connect to a central server to access resources, such as loading a website or retrieving email.
- Layered Architecture & OSI Model: The OSI model is a conceptual framework used to understand how computers communicate over a network. The model is divided into seven layers, each with specific responsibilities and area of focus. Here’s a breakdown of each layer starting with the corrected description for each
- Application Layer (Layer 7): The top layer where end-users interact with network services. It provides protocols that applications use to communicate over the network, such as HTTP for web browsing, FTP for file transfer, and SMTP for email.
- Presentation Layer (Layer 6): Handles data encryption, decryption, compression, and formatting, ensuring that data is presented in a readable way for the application layer
- Session Layer (Layer 5): Establishes, manages, and terminates connections between applications on different devices.
- Transport Layer (Layer 4): Controls the flow of data, and handles error correction. Protocols like TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) operate here
- Network Layer (Layer 3): Routing of packets across different networks from source to destinations and where IP addresses come into play.
- Data Link Layer (Layer 2): Responsible for moving frames—packets of data—between two devices error free and identifying them using a MAC Address on the same local network.
- Physical Layer (Layer 1): Physical connection between devices and how the raw bits (0s and 1s) are transmitted over a medium like cables, fiber optics, or radio waves.
- Distributed Systems: Systems where tasks are spread across multiple computers to improve performance and reliability. This is common in cloud computing environments.
- Operating Systems (OS): The software that manages hardware and software resources on a computer. Common examples include:
- Windows: Popular for personal computers, business workstations
- Linux: Widely used in servers and IT infrastructure.
- macOS: The operating system for Apple computers.
- Virtual Machines (VMs): Software emulations of physical computers. VMs allow you to run multiple operating systems on a single physical machine, each in its isolated environment.
- BYOD (Bring Your Own Devices): Organisations that allow you to bring your own device and connect them to the network
