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.
Working
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.