Operating Systems and Computer Networks – Exam Review

83 question-and-answer flashcards covering core concepts in operating systems, Linux, macOS, FreeBSD, computer networks, network topologies, and related technologies for comprehensive exam preparation.

What is the difference between application software and an operating system?

The operating system makes the computer work by managing hardware; application software uses the computer to perform specific user-focused tasks.

Why is the supervisor program considered the most important component of an operating system?

Because it is the ‘brain and heart’ of the OS, coordinating and protecting all other processes so the computer runs reliably and securely.

How do resident programs differ from non-resident programs?

Resident programs stay in memory at all times, whereas non-resident programs are loaded only when needed.

List the three main functions of an operating system.

Resource management, providing a user interface, and offering services for application execution.

What is hidden software?

System-level software that performs background tasks without direct user interaction.

Define Open-Source software.

Software whose source code is freely available for anyone to view, use, modify, and distribute.

Why do most commercial software companies withhold their source code?

To protect their revenue stream and intellectual property.

What is the GNU project?

A free-software initiative begun in 1983 by the Free Software Foundation to create a completely free Unix-like operating system.

Who founded the GNU project and the Free Software Foundation?

Richard Stallman.

What is the mission of the Free Software Foundation (FSF)?

To promote the development and use of free (zero-cost, freedom-respecting) software.

What is a Linux distribution?

A complete operating-system package that bundles the Linux kernel with utilities, applications, and installers.

Name typical components included in a Linux distribution.

The kernel, user interface, essential command-line tools, and productivity or desktop software.

What is X in Linux?

A graphical framework (the X Window System) that provides the foundation for graphical user environments.

What are the two historical families of Mac operating systems?

Classic Mac OS and macOS (formerly OS X).

For what innovation is the original Mac OS widely credited?

Popularizing the graphical user interface (GUI).

What does the “X” in Mac OS X represent?

The Roman numeral for ten.

What distinguished Classic Mac OS from many contemporaries?

It provided a fully graphical experience that required no command-line interaction.

What is the current official name of Apple’s desktop operating system?

macOS.

Does Apple offer a server variant of macOS?

Yes; it is called macOS Server (formerly OS X Server).

What is Xcode?

Apple’s integrated development environment (IDE) for building macOS, iOS, watchOS, and tvOS applications.

What was MkLinux?

An open-source project that ported the Linux kernel to PowerPC-based Macintosh computers.

What does BSD stand for?

Berkeley Software Distribution.

How does FreeBSD differ structurally from Linux?

FreeBSD’s kernel and core utilities share a single, cohesive source tree, whereas Linux distributions combine a kernel from one source with utilities from many projects.

List three key features of FreeBSD.

Advanced multitasking, strong networking capabilities, and robust memory protection.

What is binary compatibility in FreeBSD?

The ability to run binaries from other operating systems (e.g., Linux) without needing recompilation.

Give common server uses for FreeBSD.

Web hosting, email services, routing, DNS, and network-attached storage.

What is FreeBSD’s ‘real strength’?

Its reliability when running many simultaneous network services.

What is active networking?

A model where network devices can execute code embedded in data packets to customize data handling on the fly.

Define a network processor.

A programmable microchip optimized for high-speed data transmission and packet processing in networking hardware.

Name three devices that often employ network processors.

Routers, switches, and firewalls (also intrusion detection/prevention systems).

How does a client-server network differ from a peer-to-peer network?

Client-server centralizes resource management on servers; peer-to-peer distributes tasks among equal nodes.

What is a tiered (n-tier) architecture?

A design that separates client, application, and database logic into distinct layers.

Give one advantage and one disadvantage of the client-server model.

Advantage: centralized security and data management. Disadvantage: higher network traffic and server dependence.

What is a Personal Area Network (PAN)?

A very short-range network connecting a person’s devices, e.g., smartphone to smartwatch.

Define a Local Area Network (LAN).

A network covering a limited area such as a home, school, or office.

What is a Campus Area Network (CAN)?

A network that links multiple LANs across nearby buildings, often within a university or business campus.

What is a Metropolitan Area Network (MAN)?

A network that spans a city or large urban area.

Define a Wide Area Network (WAN).

A network that covers broad geographic regions, even worldwide.

Differentiate centralized and distributed WANs.

Centralized WANs keep resources and control in one hub; distributed WANs spread them across many nodes.

Compare an intranet with an extranet.

An intranet is an internal private network; an extranet extends selected internal resources to trusted external users.

List three defining characteristics of a LAN.

High data transfer rates, limited geographic range, and no need for leased telecommunication lines.

What is meant by network topology?

The physical or logical arrangement of interconnected devices in a network.

State one advantage and one disadvantage of a bus topology.

Advantage: inexpensive, minimal cabling. Disadvantage: difficult troubleshooting and a single cable fault can disable the whole network.

Which network topology is most common today?

Star topology.

What is unique about ring topology data flow?

Data travels in one direction around the loop.

Give one advantage and one disadvantage of a ring topology.

Advantage: orderly data flow; disadvantage: a single node or link failure can disrupt the entire ring.

Describe a mesh topology.

Every device connects directly to every other, providing multiple redundant communication paths.

What actually happens behind the scenes when you open a website?

Your browser issues an HTTP/HTTPS request, the server responds, and the browser renders the returned data into a webpage.

List a key pro and con of the client-server model.

Pro: centralized security; Con: server failure can halt services for all clients.

Give one general advantage and one risk of using computer networks.

Advantage: resource sharing and collaboration; Risk: potential for unauthorized access or data breaches.

Why is mesh topology considered highly reliable?

Because multiple redundant links allow communication to continue even if some links fail.

Briefly describe bus, star, ring, and mesh topologies.

Bus: single backbone cable. Star: devices connect to a central hub. Ring: devices form a closed loop. Mesh: each device connects to all others.

State two advantages of peer-to-peer networking.

Low cost and easy scalability without a dedicated server.

What is one major disadvantage of cloud computing?

Dependence on reliable internet connectivity (others include security and cost over time).

Define a computer network.

A system that links multiple devices to share data and resources efficiently.

Differentiate the Internet from the World Wide Web.

The Internet is the global network infrastructure; the Web is a service on top that uses HTTP to deliver hypertext content.

Summarize the difference between peer-to-peer and client-server structures.

Peer-to-peer shares duties equally among nodes; client-server relies on dedicated servers for services.

List two disadvantages of cloud computing.

Potential security breaches and long-term operational costs.

What does a scanner do?

Converts physical documents or images into editable digital files.

What does GPS stand for and do?

Global Positioning System; uses satellites to provide precise location and time information.

What is an IP address?

A numeric identifier assigned to a device so it can communicate on a network.

Define a wireless connection.

Data transmission using radio waves (e.g., Wi-Fi, Bluetooth) instead of cables.

What characterizes a peer-to-peer network?

Direct sharing of resources among devices with no central server.

What is an extranet?

A private network that grants controlled access to outsiders such as suppliers or partners.

What is an intranet?

An internal, organization-only network for communication and collaboration.

Define Wi-Fi.

A technology that transmits data wirelessly via radio frequencies to connect devices to local networks and the Internet.

What are email protocols?

Standards like SMTP for sending and POP3/IMAP for retrieving electronic mail.

Give two examples of wireless services.

Cellular data and satellite communication (others include Wi-Fi hotspots and Bluetooth).

What role does a bridge play in networking?

It connects or segments network sections to manage traffic and improve performance.

Describe ring topology in one sentence.

Each device connects to exactly two others, forming a closed loop through which data circulates.

What is the main vulnerability of client-server networks?

If the server fails, clients may lose access to critical resources.

Name at least three server types in a client-server network.

Web server, file server, email server, application server, terminal server.

What does client software do in a client-server environment?

It sends requests to servers and processes their responses for the user.

What does self-organization mean in peer-to-peer networks?

Nodes automatically join, leave, and maintain the network without centralized control.

Why is troubleshooting difficult in ring topology?

Because unidirectional data flow means any break disrupts the loop and makes fault isolation harder.

State two purposes of wireless services.

Providing mobile voice communication and broadband data access.

How does a bridge enhance network efficiency?

By filtering traffic and reducing unnecessary data on each segment.

Compare Windows and Linux in one sentence.

Windows is widely adopted and user-friendly, whereas Linux is open-source, flexible, and popular for servers and customization.

Contrast Windows and FreeBSD.

Windows targets general desktop use; FreeBSD focuses on performance, stability, and networking for servers.

Give one key difference between Windows and macOS.

Windows runs on a wide variety of hardware; macOS is officially supported only on Apple devices.

How does Linux compare with FreeBSD?

Linux offers many distinct distributions; FreeBSD provides an integrated, single-source system.

Summarize Linux versus macOS.

Linux prioritizes openness and configurability, while macOS emphasizes polished integration and user experience within Apple’s ecosystem.

Differentiate FreeBSD and macOS.

FreeBSD is open-source and hardware-agnostic; macOS is proprietary and limited to Apple hardware.