🌐 Computer Networks-I Quiz

The five essential components of data communication are Sender, Receiver, Message, Medium, and Protocol. A compiler is a language translator, not a networking component.

Reliability in networking is achieved by backing up critical files across multiple machines to prevent data loss in case of hardware failure.

A protocol is a standardized set of rules that both the sender and receiver agree to follow so they can understand each other's communication.

PAN (Personal Area Network) covers personal devices (like Bluetooth earphones, phones, and smartwatches) within a short range of up to 10 meters.

LAN (Local Area Network) is a network confined to a local area such as a room, building, or campus (up to 1 km).

MAN (Metropolitan Area Network) spans a larger geographical area like a city or town, typically ranging from 1 km to 100 km.

The Internet is a global network of interconnected networks and is the most prominent example of a Wide Area Network (WAN).

LANs offer higher data rates (typically 10 Mbps to 1 Gbps) with lower delays because they cover limited local physical distances.

A server is a dedicated, powerful computer that acts as a central provider of files, databases, websites, or printer access to other computers (clients).

Because all clients depend on the central server, if the server goes down, the entire network loses access to services (single point of failure).

In a P2P network, there is no centralized server. Each computer has equal status and can both request and share files directly with other peers.

ARPANET (Advanced Research Projects Agency Network) was created in 1969 and served as the direct predecessor to the modern Internet.

The Internet is the global network of physical connections (highway), whereas the WWW is an information service of websites and pages (cars/traffic) accessed via the Internet.

TCP/IP is the foundational suite of communication protocols used to interconnect network devices on the Internet.

The Interspace is a 3D collaborative environment (like the Metaverse) allowing multiple users to communicate and share dynamic 3D virtual spaces.

Circuit switching reserves a physical path through nodes for the exclusive use of the connection for its entire duration.

Traditional voice telephony reserves a physical line (circuit) for the duration of a call, which is circuit switching.

Message switching sends the entire message to a node, which stores it, waits for the next link to open, and then forwards it.

In packet switching, files are broken into packets that are routed dynamically and independently, then reassembled at the destination.

A network packet contains a Header (control info, addresses), a Payload (the actual data), and a Trailer (error-detection bytes like CRC).

Bandwidth is the theoretical maximum data-carrying capacity of a communication channel, measured in Hertz (Hz) or bits per second (bps).

Modern data rates are measured in bits per second, commonly in Mbps (Megabits per second) or Gbps (Gigabits per second).

Bit Rate is the number of bits sent per second. Baud Rate is the number of signal state transitions per second. One signal change can represent multiple bits.

Attenuation is the reduction of signal strength as it propagates through any transmission medium over distance.

Jitter is the variance in latency (packet arrival delay), causing packet delivery to be irregular, which affects real-time traffic like video calls.

Latency is the end-to-end time delay taken for a data packet to travel from the sender to the receiver.

Twisted pair cables feature pairs of insulated copper wires twisted together to cancel out electromagnetic interference (EMI).

RJ-45 (Registered Jack 45) is the standard 8-pin connector used to connect Ethernet twisted pair cables to switches/PCs.

Coaxial cable contains a central copper core, dielectric insulation, metallic braid shielding, and a outer PVC jacket.

BNC (Bayonet Neill-Concelman) connectors are bayonet-style quick-connect/disconnect connectors used with coaxial cables.

Optical fiber transmits data as light pulses that propagate down a central glass core by bouncing off the cladding via total internal reflection.

Optical fibers offer massive bandwidth, extremely low attenuation, and are completely immune to EMI because they transmit light instead of electricity.

Single-Mode Fiber (SMF) has a narrow core (~8-10 microns) and uses laser light for long distances. Multi-Mode Fiber (MMF) has a wider core (~50-62.5 microns) and uses LEDs for shorter campus runs.

Terrestrial microwave uses highly focused, high-frequency signals that travel in straight lines, requiring a clear line-of-sight (LOS) path.

Microwaves require line-of-sight propagation. Due to the Earth's curvature and terrain blockages, towers are elevated to maximize communication distance.

Uplink is the transmission link from an Earth station up to the satellite. Downlink is the transmission link from the satellite back down to Earth stations.

A satellite in a GEO (Geostationary Earth Orbit) rotates in sync with the Earth's rotation, making it seem stationary over a fixed longitude.

Infrared (IR) operates at light frequencies that are blocked by solid walls, making it ideal for short-range, single-room remote controls.

Bluetooth was named after 10th-century Danish King Harald Bluetooth, who united Scandinavian tribes under one crown. The tech unites device communication protocols.

In a star topology, each computer is connected to a central hub or switch via a dedicated cable segment.

The central switch in a star topology is a single point of failure; if it stops working, all interconnected nodes lose communication.

Terminators are placed at the ends of a bus network's shared cable to absorb signals and prevent reflection/collisions.

Tree topology has a hierarchical structure where central hubs of multiple star networks are connected to a root hub.

A MAC (Media Access Control) address is a permanent 48-bit (6-byte) physical address burned into the NIC by the manufacturer.

IPv4 addresses are 32 bits long (written in dotted decimal). IPv6 addresses are 128 bits long (written in colon hexadecimal).

DNS (Domain Name System) translates human-readable hostnames into IP addresses that computers use to route packets.

The Top-Level Domain is the last segment of the domain name, in this case .in (country code TLD for India).

The IP address 127.0.0.1 is reserved as the loopback address, referring to the local computer itself.

Star topology provides fault isolation. If a node's cable breaks, only that node is disconnected; other nodes communicate normally.