Computer Networking Overview

Computer Networking Study Notes

Network Protocols

• Definition: Set of rules governing data communications between devices in a network.
• Types:
  • Communication Protocols: TCP, UDP, HTTP, FTP, etc.
  • Network Management Protocols: SNMP, ICMP.
• Functions:
  • Define data formats, timing, and error handling.
  • Ensure reliable data transfer and communication efficiency.

OSI Model

• Overview: A conceptual framework used to understand network interactions in seven layers.
• Layers:
  1. Physical: Transmission of raw bitstreams over physical medium.
  2. Data Link: Node-to-node data transfer and error detection.
  3. Network: Routing of data packets (IP).
  4. Transport: End-to-end communication (TCP, UDP).
  5. Session: Managing sessions between applications.
  6. Presentation: Data translation, encryption, and compression.
  7. Application: User interface and application services.

TCP/IP Framework

• Overview: The backbone of the internet; a suite of communication protocols.
• Layers:
  1. Link Layer: Handles physical network hardware and protocols.
  2. Internet Layer: Manages packet routing (IP).
  3. Transport Layer: Provides reliable or unreliable delivery (TCP vs. UDP).
  4. Application Layer: Interfaces with end-user applications (HTTP, FTP).
• Key Features:
  • Protocols are designed to be modular and interoperable.
  • Focus on connectionless and connection-oriented communication.

Routing Algorithms

• Purpose: Determine optimal paths for data packets across networks.
• Types:
  • Static Routing: Manual configuration; unchanging paths.
  • Dynamic Routing: Automatically adapts to changing network conditions (e.g., RIP, OSPF, BGP).
• Metrics: Factors used to determine the best route (e.g., hop count, bandwidth, latency).
• Protocols:
  • Distance Vector Protocols: Share routing tables (e.g., RIP).
  • Link State Protocols: Use a complete network map (e.g., OSPF).

Network Security

• Importance: Protects data integrity, confidentiality, and availability in networks.
• Threats:
  • Malware, phishing, DDoS attacks, eavesdropping.
• Security Measures:
  • Firewalls: Control incoming and outgoing traffic.
  • Encryption: Secures data transmission (e.g., SSL/TLS).
  • Authentication: Verifies identity of users/devices (e.g., passwords, biometrics).
  • Intrusion Detection Systems (IDS): Monitors for malicious activity.
• Best Practices:
  • Regular updates and patch management.
  • Strong password policies and multi-factor authentication.
  • Security awareness training for users.

Network Protocols

• Definition: Rules for data communications in a network.
• Types:
  • Communication Protocols: Examples include TCP for reliable transmission, UDP for low-latency, HTTP for web communication, and FTP for file transfers.
  • Network Management Protocols: SNMP for network devices and ICMP for error messaging and diagnostics.
• Functions: Establish data formats, timing protocols, and error handling mechanisms; enhance reliability and communication efficiency.

OSI Model

• Overview: Framework to understand network interactions divided into seven distinct layers.
• Layers:
  • Physical Layer: Handles the transmission of raw bitstreams over physical media.
  • Data Link Layer: Facilitates node-to-node data transfer and error detection.
  • Network Layer: Responsible for data packet routing using IP addressing.
  • Transport Layer: Manages end-to-end communication, primarily through TCP and UDP.
  • Session Layer: Controls sessions between applications, establishing and maintaining connections.
  • Presentation Layer: Translates, encrypts, and compresses data before sending.
  • Application Layer: Interfaces directly with end-user applications, providing services like email and web browsing.

TCP/IP Framework

• Overview: Fundamental communication protocol suite for the internet.
• Layers:
  • Link Layer: Handles the interaction with physical network hardware and specifications.
  • Internet Layer: Responsible for routing packets via the Internet Protocol (IP).
  • Transport Layer: Delivers data reliably (TCP) or with minimal latency (UDP).
  • Application Layer: Engages with user-level applications such as HTTP and FTP.
• Key Features: Modularity and interoperability among protocols; support for both connection-oriented and connectionless communication methods.

Routing Algorithms

• Purpose: Establish optimal paths for data packets in networks.
• Types:
  • Static Routing: Paths are manually set and do not change unless manually reconfigured.
  • Dynamic Routing: Routes adapt automatically to network changes through protocols like RIP, OSPF, and BGP.
• Metrics: Factors including hop count, bandwidth, and latency are used to evaluate the best routing paths.
• Protocols:
  • Distance Vector Protocols: Share route information based on distance (e.g., RIP).
  • Link State Protocols: Use a network map to make routing decisions (e.g., OSPF).

Network Security

• Importance: Safeguards data integrity, confidentiality, and availability in networks.
• Threats: Includes risks such as malware, phishing, DDoS attacks, and eavesdropping.
• Security Measures:
  • Firewalls: Monitor and control network traffic based on predetermined security rules.
  • Encryption: Protects data in transmission, leveraging protocols like SSL/TLS.
  • Authentication: Confirms the identities of users and devices through methods like passwords and biometrics.
  • Intrusion Detection Systems (IDS): Monitors network or system activities for malicious activities.
• Best Practices:
  • Implement regular updates and patch management for systems.
  • Establish strong password policies and encourage multi-factor authentication.
  • Provide security awareness training to users to mitigate risks.

Explore the essential concepts of computer networking, including network protocols and the OSI model. This quiz covers key rules governing data communications and the TCP/IP framework, helping you understand how networks operate effectively. Enhance your knowledge of networking basics and terminology.