What are Basic terminologies in computer networking?

Basic Terminologies of Computer Networks

• Network: A collection of computers and devices connected together to enable communication and data exchange.

• Nodes: Devices connected to a network, including computers, servers, printers, routers, switches, and others.

• Protocol: A set of rules governing data transmission over a network (e.g., TCP/IP, HTTP, FTP).

• Topology: The physical and logical arrangement of nodes in a network. Common topologies include bus, star, ring, mesh, and tree.

• Service Provider Networks: Networks that allow users to lease network capacity and functionality from providers, including wireless communications and data carriers.

• IP Address: A unique numerical identifier assigned to every device on a network, used for identifying devices and enabling communication.

• DNS (Domain Name System): A protocol that translates human-readable domain names (e.g., www.google.com) into IP addresses.

• Firewall: A security device that monitors and controls incoming and outgoing network traffic to protect networks from unauthorized access and threats.

Types of Enterprise Computer Networks

• LAN (Local Area Network): Covers a small area (e.g., an office or home), used to connect devices within a building or campus.

• WAN (Wide Area Network): Covers a large geographic area, connecting LANs for long-distance communication.

• Cloud Networks: Similar to WANs, hosted on public or private cloud service providers and consist of virtual routers and firewalls.

Types of Computer Network Architecture

• Client-Server Architecture: Involves nodes that can be servers or clients, where the server manages client behavior.

• Peer-to-Peer Architecture (P2P): No central server; each device can act as both client and server.

Network Devices

• Network Devices: Include routers, switches, hubs, and bridges that facilitate communication between different devices.

Network Topology

1. Bus Topology: All devices connect to a single central cable (the bus). If the main cable fails, the network goes down.

2. Star Topology: All devices connect to a central hub or switch. If one device fails, others are unaffected, but if the hub fails, the network stops working.

3. Ring Topology: Devices are connected in a circular loop; data travels in one direction. A failure in one device can affect the entire network.

4. Mesh Topology: Every device connects to every other device, providing multiple data paths for redundancy.

5. Tree Topology: A combination of star and bus topology, suitable for organizing large networks.

6. Hybrid Topology: Combines two or more different topologies for flexibility and customization.

OSI Model

• OSI (Open Systems Interconnection): A reference model that specifies communication protocols and functionalities for each layer. It has 7 layers:

  1. Physical Layer
  2. Data Link Layer
  3. Network Layer
  4. Transport Layer
  5. Session Layer
  6. Presentation Layer
  7. Application Layer

Network Protocols

• TCP/IP: Foundational protocol suite of the internet, ensuring reliable communication and data delivery.

• HTTP/HTTPS: Protocols for transmitting web pages, with HTTPS providing secure communication.

• SMTP: Protocol for sending emails, working with POP3 and IMAP for retrieval.

• FTP: Protocol for transferring files between computers.

• DHCP: Automatically assigns IP addresses to devices on a network.

• DNS: Translates domain names into IP addresses for seamless navigation.

Unique Identifiers of Network

• Hostname: Unique name associated with each device in the network.

• IP Address: Logical address assigned to each device, uniquely identifying it across the network.

• MAC Address: Physical address associated with a device's NIC, assigned at manufacturing.

• Port: Logical channel for data transfer, identified by a port number.

• Socket: The combination of an IP address and port number.

Other Related Concepts

• DNS Server: Translates web addresses into IP addresses for easier navigation.

• ARP (Address Resolution Protocol): Converts an IP address into its corresponding MAC address.

• RARP (Reverse Address Resolution Protocol): Provides an IP address given a physical address (now obsolete).

How DNS Works

1. User inputs a domain name.
2. Device sends a DNS query to the DNS resolver.
3. Resolver checks its cache; if not found, it queries the root DNS server.
4. Root server provides the TLD server address.
5. TLD server directs to the authoritative DNS server.
6. Authoritative server provides the IP address.
7. Resolver caches the IP and sends it to the user.
8. User accesses the website.

Network Security

Key aspects of network security include:

• Firewalls: Monitor and control network traffic.
• Encryption: Protects data from unauthorized access.
• Intrusion Detection Systems (IDS): Monitor for suspicious activity.
• Access Control: Restricts resource access based on user identity.
• Regular Updates and Patching: Keeps software and hardware secure.

Why Use Computer Networks?

• Fast and Easy Communication: Enables digital communication like emails, messaging, and video calls.
• More Storage Space: Offers storage solutions, reducing reliance on physical files.
• Easier Sharing of Information: Simplifies resource and information sharing.
• Better Security: Provides built-in security features to protect data.

Conclusion

Understanding computer networking basics is essential for navigating today's interconnected world, enabling information exchange, supporting applications, and underpinnings of the internet.