Computer Networks

At the Network Layer, the Protocol Data Unit (PDU) is called a Packet or Datagram. This layer is responsible for routing and forwarding packets across networks.

In packet switching, data is divided into packets of fixed or variable size, which are transmitted independently over the network. This contrasts with circuit switching, where a dedicated continuous channel is established.

In a client-server network, some computers are designated as servers that provide resources or services, while others act as clients that request and use those services. This is the primary characteristic distinguishing it from peer-to-peer networks.

Packet switching reduces bandwidth usage by dividing data into packets that share network paths dynamically, unlike circuit switching which requires a dedicated path for the entire communication session. This makes packet switching more efficient and flexible.

HTTP is an application-layer protocol used for transmitting hypertext requests and information on the web, which corresponds to the Application Layer (Layer 7) of the OSI model.

A key feature of a Peer-to-Peer (P2P) network is that it allows a small number of computers, often fewer than ten, to connect directly and share resources without a dedicated server. Options A and C describe client-server networks, and D is a general networking concept not specific to P2P.

Circuit switching establishes a dedicated communication path between two parties for the duration of the connection, which is characteristic of traditional telephone calls. The other options use packet switching, where data is sent in packets over shared networks.

Packet switching divides data into packets that are sent independently over the network, as used in Internet communication like email and web browsing. This contrasts with circuit switching, which establishes a dedicated path, as in landline telephone calls.

Circuit switching involves establishing a dedicated communication path between two nodes for the duration of the communication session, ensuring a constant and exclusive connection. This contrasts with packet switching, where data is sent in packets over shared networks without a dedicated path.

Multiplexing is the technique used to send multiple calls or data streams over a single communication line by combining them into one signal, making option D correct.