Unit 1: Introduction to Computer Networks Flashcards
(25 cards)
What is a computer network?
A computer network is a system in which multiple computers or devices are connected to share resources and information. These devices use communication protocols over digital interconnections.
Why are reference models used in networking?
Reference models like OSI and TCP/IP provide a standardized framework for understanding and designing networks. They help in interoperability, modular development, and troubleshooting.
What is the purpose of the OSI model?
The OSI model divides the networking process into seven layers to standardize communications and provide a conceptual framework for understanding interactions between different systems.
What are the layers of the OSI model?
The OSI model has seven layers: Physical Data Link Network Transport Session Presentation Application
How does the TCP/IP model differ from the OSI model?
The TCP/IP model has four layers: Link Internet Transport Application. Unlike the theoretical OSI model, TCP/IP is more practical and used in real-world networks.
Why is TCP/IP widely used?
TCP/IP is used because it is robust, scalable, interoperable, and forms the basis of the modern Internet.
What is meant by peer-to-peer communication in networking?
Peer-to-peer (P2P) communication involves systems acting as both clients and servers, allowing direct data exchange without relying on centralized servers.
What is the role of sockets in networking?
A socket is an endpoint for sending or receiving data across a computer network. It includes an IP address and a port number.
Why are ports used in networking?
Ports identify specific processes or services on a device. For example, port 80 is used for HTTP, and port 443 for HTTPS.
What is data encapsulation in networking?
Data encapsulation involves wrapping data with protocol-specific headers as it moves down the OSI layers for transmission, and removing them at the receiver.
What is a repeater and when is it used?
A repeater is a network device that regenerates and amplifies signals to extend the transmission distance.
What is the difference between a hub and a switch?
A hub broadcasts data to all connected devices, while a switch sends data only to the intended recipient based on MAC addresses.
Why is a switch preferred over a hub?
Switches are more efficient and secure, reducing collisions and bandwidth wastage, unlike hubs which cause network congestion.
What is a bridge in networking?
A bridge connects two different LAN segments and filters traffic to reduce collisions.
What is a router and what is its function?
A router connects different networks and forwards data packets based on IP addresses. It is essential for Internet connectivity.
What is the function of a gateway?
A gateway acts as a protocol converter, connecting different types of networks (e.g., LAN to Internet) and translating data formats.
Why is a MAC address needed if we have IP addresses?
MAC addresses identify devices at the data link layer within the same network, while IP addresses are used at the network layer for inter-network communication.
What is network topology?
Network topology refers to the physical or logical arrangement of nodes and links in a network, such as bus, ring, star, mesh, etc.
What is the difference between physical and logical topology?
Physical topology is the actual layout of cables and devices, while logical topology defines the data flow path regardless of physical layout.
Why is mesh topology more fault-tolerant?
Mesh topology has multiple paths between nodes, so a failure in one link doesn’t disrupt communication.
What is the benefit of using layered models in networking?
Layering simplifies network design, allows interoperability, and isolates issues for easier troubleshooting and updates.
What is the difference between connection-oriented and connectionless communication?
Connection-oriented communication (e.g., TCP) establishes a reliable connection before data transfer, whereas connectionless (e.g., UDP) sends data without setup.
Why is the application layer important in the OSI model?
The application layer provides network services directly to user applications such as email, FTP, and web browsing.
What is the transport layer responsible for?
The transport layer ensures reliable data transfer through mechanisms like segmentation, acknowledgment, flow control, and error handling.
