Computer network is a collection of interconnected devices that communicate with each other to exchange data and resources. It enables efficient communication and supports services like email, file sharing, and internet access.
Nodes are physical devices such as computers, mobiles, or printers.
Routers and switches control the flow of information.
Transmission media carry data from one device to another.
Wired media includes Ethernet and optical fiber cables.
Computer network operates by enabling devices to communicate and exchange data using a shared communication system. Each device in the network follows predefined rules to ensure that data is transmitted accurately, efficiently, and securely.
A network consists of nodes such as computers, servers, routers, and switches that send or receive data.
These nodes are connected through links, which may be wired (cables, optical fiber) or wireless (Wi-Fi, radio signals).
When data is sent, it is broken into small packets and transmitted across the network.
Protocols define how data packets are formatted, transmitted, received, and acknowledged.
Each device is identified by a unique IP address, which ensures data reaches the correct destination.
Network devices like switches and routers forward data packets along the best available path.
Security mechanisms, such as firewalls, monitor traffic and allow or block data based on security rules.
Types of Computer Network Architecture
Computer Network falls under these broad Categories:
Client-Server Architecture: Represents a type of computer network architecture in which nodes function as servers or clients, where the server manages client behavior, known as Client-Server Architecture.
Peer-to-Peer Architecture: Operates without any central server, allowing each device to act as either a client or a server, known as P2P (Peer-to-Peer) Architecture.
Network Devices
These are physical devices that connect computers, printers and other electronic equipment to a network and enable data sharing, transferring and managing.
1. Router
Functions as a networking device that connects multiple networks and directs data between them.
Connects local networks to the internet
Determines the best path for data packets
Uses IP addresses to forward data correctly
2. Switch
Connects devices within the same network and manages internal data communication.
Connects computers, printers, and servers
Sends data only to the intended device
Improves network efficiency and performance
3. Hub
Acts as a basic device that connects multiple devices within a network.
Broadcasts data to all connected devices
Does not filter or manage traffic
Less secure and less efficient than a switch
4. Bridge
Connects two network segments and filters traffic between them.
Reduces unnecessary data transmission
Improves network performance
Works using MAC addresses
5. Gateway
Connects two different networks that use different protocols.
Translates data between different systems
Enables communication between dissimilar networks
Commonly used to connect private networks to external networks
6. Access Point (AP)
Provides wireless connectivity to devices in a network.
Extends a wired network into Wi-Fi
Allows mobile devices to connect wirelessly
Improves network coverage area
7. Modem
Converts digital data into signals suitable for transmission and vice versa.
Connects a home or office network to the ISP
Converts digital signals to analog and back
Enables internet access
8. Firewall
Security device that monitors and controls network traffic.
Blocks unauthorized access
Filters incoming and outgoing data
Protects networks from cyber threats
Goals and Uses
Resource Sharing: Allow multiple users to share hardware, software, and data resources efficiently.
Internet and Cloud Access: Enable access to the Internet, online services, and cloud-based applications.
Cost Efficiency: Reduce operational and infrastructure costs through shared resources and centralized systems.
Reliability and Availability: Improve system reliability using backup paths and fault-tolerant mechanisms.
Scalability and Growth: Support easy expansion by adding new devices and services as demand increases.
Security and Control: Protect data and network resources using authentication, access control, and monitoring.
