Computer Networks

Both a modem and a network card are used for internet connectivity. A modem modulates and demodulates signals for internet access, while a network card (NIC) allows a device to connect to a network, including the internet.

In a star topology, each computer is directly connected to a central computer or hub, making option B the correct answer. Other topologies like bus, ring, and node do not have this direct central connection.

A proxy server acts as an intermediary between a client and the internet, primarily processing client requests for web pages by forwarding them and returning the responses. This helps with caching, filtering, and anonymity.

Tree topology combines characteristics of star and bus topologies, where groups of star-configured networks are connected to a linear bus backbone, making it suitable for hierarchical network structures.

MODEM stands for Modulator-Demodulator, which is a device that modulates digital signals into analog for transmission and demodulates incoming analog signals back into digital form. Option A correctly reflects this full form.

A ring topology connects each device to exactly two other devices, forming a closed loop. This allows data to travel in one or both directions around the ring.

Network Architecture defines the design and communication structure of a network, including how devices are interconnected and how data flows between them. It encompasses the arrangement and interaction of network components rather than physical device design or cable types.

At the Data Link Layer of the OSI model, the Protocol Data Unit (PDU) is called a Frame. Segments are PDUs at the Transport Layer, Packets at the Network Layer, and Bits at the Physical Layer.

In a Peer-to-Peer network model, all devices share resources directly without relying on a central server, unlike Client-Server networks where a central server manages resources. Cloud Networks and Circuit Switching do not describe this resource-sharing model.

The Protocol Data Unit (PDU) at the Transport Layer is called a Segment. Frames are at the Data Link Layer, Bits at the Physical Layer, and Packets at the Network Layer.