Data Representation and Transmission in Computer Networks

Explore how different data types (text, numbers, images, etc.) are represented digitally and transmitted across computer networks. This guide explains character encoding (ASCII, Unicode), binary data representation, and the methods used for efficient and reliable data transfer.

Data Representation and Transmission in Computer Networks

Introduction

Computer networks transmit various types of data (text, numbers, images, audio, video). This article explains how different data types are represented digitally and transmitted across a network.

Data Types and Their Digital Representation

1. Textual Data

Text is represented using character encoding standards, which map characters to numerical codes. These codes are then converted into binary (0s and 1s) for transmission.

Unicode: A widely used standard that assigns unique codes to characters from virtually all languages, including emojis. ASCII is a smaller subset of Unicode.

Example: The character 'H' is represented by U+0048 in Unicode.

Common File Extensions: .txt, .doc, .docx, .pdf

2. Numerical Data

Numbers are directly converted into their binary equivalents for transmission. Different formats exist for representing numbers (integers, floating-point numbers, etc.).

Example: The decimal number 780 is represented as 1100001100 in binary.

3. Image Data

Images are composed of pixels. Each pixel has a value representing its color or intensity. Grayscale images use a single value per pixel; color images usually use three values (Red, Green, Blue - RGB).

• Grayscale: 0 (black) to 255 (white).
• Color (RGB): Three values (0-255) for red, green, and blue components.

These values are converted into binary and transmitted as a stream of bits.

Common File Extensions: .jpg, .jpeg, .png

4. Audio Data

Audio is initially captured as an analog signal (continuous waveform). This is then converted into a digital format using techniques like Pulse Code Modulation (PCM), which involves sampling (taking measurements at regular intervals), quantization (assigning discrete values to the samples), and encoding the resulting values into binary.

Common File Extensions: .mp3, .wav, .m4a, .aac

5. Video Data

Video is a sequence of images (frames) displayed rapidly to create motion. Each frame is an image, which can be encoded in various ways. Video data includes both image data and, often, an audio component.

Key Video Characteristics: Frames per second (FPS), video duration, resolution, bit depth.

Common File Extensions: .mp4, .mov, .avi

Conclusion

Different data types are represented and transmitted using various techniques. Understanding these methods is important for designing efficient and reliable computer networks.