Data Communications and Networking Mind Map

Data Communications and Networking💻🌐

NetworkingData Communications

Overview and Objectives

Importance of Networks

Data Transmission in Distributed Systems

Real-Time Communication

E-commerce

Social Media

Chapter Objectives

Understand network components and types

Comprehend the role of network layers and standards

Recognize cybersecurity concerns

Note key trends in communications and networking

Why Networks are Important

Data Transmission Scale

Daily Internet data transfer exceeded 3,000 petabytes by 2016.

Importance of Networks

Data transmission in distributed systems

Real-time communication

E-commerce

Social media

Examples of Scale

Netflix accounted for a significant portion of internet traffic.

Amazon achieved high sales volume.

Facebook users contributed billions of interactions daily.

Basic Concepts in Data Communications

Data Communications

Movement of computer information via electrical or optical systems.

Telecommunications

A broader term encompassing voice, video, and data transmission, often over long distances.

Basic Network Components

Client

User devices accessing the network (e.g., desktops, tablets).

Server

Stores and transmits data to clients (e.g., web servers).

Circuit

Connection pathway between client and server, using copper, fiber optic, or wireless mediums.

Types of Networks

By Geographic Scope

Local Area Networks (LANs)

Small area coverage (like a building)

Wireless LAN (WLAN): When using wireless circuits

Backbone Networks (BNs)

Connects various networks

May span miles

High speed

Wide Area Networks (WANs)

Covers the largest area (spanning hundreds to thousands of miles)

Composed of leased circuits

By Access Type

Intranet

Internal network sharing within an organization

Extranet

Extends access to invited users outside the organization

Network Models

Purpose

Divides functions into layers for structured communication

Models

Open System Interconnection (OSI) Model

A layered model for understanding network communication

Internet Model (TCP/IP)

The more widely adopted model

Layers

Application Layer

Provides network services to applications (e.g., email, web browsing)

Transport Layer

Manages end-to-end data transfer between applications (e.g., TCP, UDP)

Network Layer

Handles logical addressing and routing of data packets (e.g., IP)

Data Link Layer

Provides reliable data transfer over a physical link (e.g., Ethernet)

Physical Layer

Transmits and receives raw data bits over a physical medium (e.g., cables, wireless)

Encapsulation

Each layer adds a Protocol Data Unit (PDU), acting like nested envelopes for structured transmission.

Protocols and PDUs

Protocol

Sets rules for data communication

Protocol Data Unit (PDU)

Encapsulated information added at each layer

Layer-Specific PDUs

Application Layer: Packets

Transport Layer: Segments

Network Layer: Packets

Data Link Layer: Frames

Physical Layer: Bits

Advantages and Disadvantages of Layered Models

Advantages

Modular structure: Easier to develop and maintain

Ease of troubleshooting: Issues can be isolated to specific layers

Application developers focus only on the application layer

Disadvantages

Can be inefficient due to encapsulation processing

Increased overhead (costs)

Network Standards

Purpose

Ensure compatibility between hardware and software from different vendors

Types

De jure Standards

Formalized by industry or government (e.g., IEEE 802.3)

De facto Standards

Widely accepted but informal, potentially becoming de jure (e.g., Windows)

Key Network Protocols

Transport Layer Protocols

TCP (Transmission Control Protocol)

Reliable data transmission with higher overhead (20-24 bytes)

PDU called a segment

UDP (User Datagram Protocol)

Less reliable but suitable for time-sensitive data

PDU called a segment (4-8 bytes)

Network Layer Protocols

Internet Protocol (IP)

IPv4: Common with 32-bit addressing

IPv6: 128-bit addressing, slowly being adopted due to IPv4 exhaustion