Applied Computing Networks SAC Revision

What is a network?

A group of connected devices that share data and resources.

What are the different types of networks (LAN

WAN, MAN, etc.)?,LAN connects computers within a limited geographic area like a home or office; WAN spans large geographic distances across countries or globally; MAN spans a city-sized region or campus.

What is the role of a router in a network?

Directs data packets between separate networks using IP addresses to find the best path.

What is the difference between TCP and UDP?

TCP is connection-oriented, reliable, and checks for errors; UDP is connectionless, faster, and does not guarantee packet delivery.

What is the purpose of DNS?

Translates human-readable domain names into numeric IP addresses so computers can locate servers.

What is the OSI model and its layers?

A conceptual seven-layer framework explaining how data travels across communication systems: Physical, Data Link, Network, Transport, Session, Presentation, and Application.

What is the difference between IPv4 and IPv6?

IPv4 uses 32-bit addresses while IPv6 uses 128-bit addresses to support a vastly larger number of devices.

What is the purpose of a subnet mask?

Divides an IP address into two parts: the network identifier and the host identifier.

What is NAT and why is it used?

Translates private internal IP addresses into a single public IP address to enable multiple devices to share one internet connection and enhance security.

What is DHCP and how does it work?

Dynamically and automatically assigns IP addresses and configuration parameters to devices joining a network.

What is the difference between a switch and a hub?

A hub broadcasts incoming data packets to all connected ports indiscriminately; a switch forwards data packets only to the specific intended device using MAC addresses.

What is the role of a firewall?

Monitors, filters, and blocks incoming and outgoing traffic based on predetermined security rules.

What is a modem and its function?

Modulates digital computer signals into analog signals for transmission over lines and demodulates incoming signals back into digital data.

What is a load balancer and how does it work?

Distributes incoming traffic efficiently across multiple servers to prevent overload, ensure high availability, and optimize response times.

What is a wireless access point (WAP)?

Hardware device that creates a wireless local area network, allowing Wi-Fi devices to connect to a wired network.

What is HTTP and its role in web communication?

Protocol governing the transfer of web pages, documents, and multimedia data between web servers and client browsers.

What is FTP and how is it used?

Standard network protocol used for uploading and downloading files between client computers and servers.

What is SMTP and its role in email?

Communication protocol responsible for transmitting and relaying outgoing emails between mail servers.

What is POP3 and IMAP

and how do they differ?,POP3 downloads emails directly to a single local device and deletes them from the server; IMAP keeps emails stored on the server and synchronizes them across multiple devices.

What is SSH and its purpose?

Cryptographic protocol providing a secure, encrypted channel for administering systems and executing commands on remote computers.

What is a virus and how does it spread?

Malicious program code that replicates by attaching itself to legitimate host files or applications and executing when the host runs.

What is a worm and how is it different from a virus?

Self-replicating malware that travels independently across network vulnerabilities without needing a human-run host file or program.

What is a Trojan and how does it work?

Malicious software disguised as legitimate, helpful programs to trick users into downloading and executing it.

What is a firewall and its role in network security?

Security barrier that inspects traffic streams and applies access control rules to block unauthorized access or malicious packets.

What is a VPN and how does it provide security?

Encapsulates and encrypts internet traffic through a tunnel, masking IP addresses and securing communications over public networks.

What is a DDoS attack and how does it work?

Malicious attempt to disrupt a targeted server or service by overwhelming it with a massive flood of bogus requests from multiple compromised sources.

What is phishing and how can you protect yourself from it?

Social engineering tactic using fraudulent messages or fake websites to steal sensitive credentials; protection includes verifying sender authenticity, inspecting URLs, and using multi-factor authentication.

What is encryption and why is it important?

Mathematical process of converting plain text into unreadable ciphertext using algorithms and keys to ensure data confidentiality.

What is a security audit and why is it necessary?

Systematic evaluation and assessment of an organization's information system security policies, controls, and vulnerabilities.

What is patch management and why is it important?

Systematic acquisition, testing, and installation of code updates to fix software bugs and close security vulnerabilities.

What is the ping command and how is it used for troubleshooting?

Diagnostic utility that sends ICMP Echo Request messages to test host reachability and measure round-trip latency.

What is the traceroute command and how does it help in troubleshooting?

Diagnostic tool that maps the exact packet path and measures transit delays across routers from source to destination.

What is the netstat command and what information does it provide?

Command-line tool displaying active network connections, routing tables, interface statistics, and listening ports.

How can you troubleshoot a slow network connection?

Monitor bandwidth consumption, reboot hardware, run speed tests, examine physical cables, and evaluate wireless signal strength or interference.

How can you troubleshoot a network access issue?

Confirm IP configurations, inspect physical links, verify switch/router port status, and test connectivity to gateway.

What is the difference between a static IP address and a dynamic IP address?

A static IP is manually configured and remains permanently assigned; a dynamic IP is temporarily assigned automatically by a DHCP server and subject to change.

How can you troubleshoot a DNS resolution issue?

Verify DNS server addresses, clear local resolver cache (ipconfig /flushdns), and query alternative public DNS resolvers.

What is a loopback address and how is it used?

Reserved IP address (127.0.0.1) used by a device to route outbound traffic back to itself for internal diagnostics and testing.

How can you troubleshoot a DHCP issue?

Verify server service status, check scope allocation limits, and force an IP lease renewal (ipconfig /renew).

What is port forwarding and how is it used?

Router configuration that maps incoming requests on a specific communication port to a designated internal device behind a firewall.

What is a network topology and what are the common types?

Arrangement and geometric layout of interconnected devices and nodes; common types include Star, Bus, Ring, and Mesh.

What is a network diagram and why is it important?

Visual schematic representation showing hardware components, links, and layout to simplify infrastructure management and troubleshooting.

What is network documentation and why is it essential?

Comprehensive written record detailing hardware inventories, configurations, IP schemas, and operating procedures for maintenance and compliance.

What is network monitoring and why is it important?

Continuous observation of availability, bandwidth utilization, and health metrics to proactively detect anomalies before failures occur.

What is network virtualisation and how does it benefit organisations?

Abstraction technique combining hardware and software resources into a single software-based administrative entity to boost flexibility and resource utilization.

What is cloud networking and how does it differ from traditional networking?

Infrastructure where management and control functions are hosted and accessed remotely via cloud providers rather than relying exclusively on on-premises physical hardware.

What is SDN (Software-Defined Networking) and how does it work?

Architecture that decouples the control plane (management logic) from the data plane (hardware forwarding), enabling centralized software programmability.

What is network automation and why is it important?

Use of software scripts and orchestration tools to execute configuration, provisioning, and management tasks automatically to minimize human error.

What are network security best practices and why are they important?

Industry guidelines involving strong authentication, regular patch updates, robust encryption, perimeter firewalls, and routine backups to mitigate risks.

What is disaster recovery planning and why is it important?

Documented set of procedures and policies designed to recover IT infrastructure, data, and business operations following a major disruption or cyberattack.

What is the Internet of Things (IoT) and how is it impacting networking?

Ecosystem of embedded smart physical objects that communicate over internet connections, dramatically increasing density, traffic volume, and security challenges.

What is 5G and how will it change networking?

Fifth-generation cellular wireless technology delivering ultra-high data speeds, minimal latency, and massive device concurrency.

What is edge computing and how does it differ from cloud computing?

Decentralized paradigm processing data locally near the physical source rather than transmitting raw data back to centralized remote data centers.

What is Network Function Virtualisation (NFV) and how does it benefit organisations?

Practice of running network services (like routing, firewalls, load balancing) as software virtual appliances on standard servers instead of dedicated hardware.

What is artificial intelligence (AI) and how is it being used in networking?

Machine learning algorithms and cognitive models applied to analyze traffic patterns, predict bottlenecks, automate provisioning, and proactively detect threats.

What is blockchain and how can it be applied to networking?

Decentralized, immutable distributed ledger technology providing cryptographic verification for secure device authentication, auditing, and trust management.

What is the role of cybersecurity in modern networking?

Comprehensive discipline of safeguarding confidentiality, integrity, and availability of infrastructure and information against malicious threats and breaches.

What is network slicing and how can it be used to improve network efficiency?

Virtualization technique partitioning a single physical network infrastructure into multiple independent virtual networks tailored to specific performance requirements.

What is the future of networking and what trends can we expect to see?

Trajectory toward autonomous intent-based systems driven by pervasive AI, edge processing, deep automation, quantum-resistant encryption, and ultra-dense wireless topologies.

What are the challenges and opportunities in the field of networking today?

Obstacles include expanding attack surfaces, exponential data growth, and architectural complexity; opportunities include digital transformation via AI, cloud agility, and 5G/IoT expansion.