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Data Compression

Compression algorithms and their applications in networking

Key Algorithms

Huffman, LZW, RLE, and modern compression techniques

Applications

Web compression, file storage, multimedia streaming

Interactive Tools

Compression simulators and performance analyzers

Compression Topics

Compression Overview Details

Compression Fundamentals

Data Compression

Process of encoding data using fewer bits than original representation

Compression Ratio

Ratio of uncompressed size to compressed size

Formula: Compression Ratio = Original Size / Compressed Size
Example: 100KB file compressed to 25KB = 4:1 ratio
Redundancy

Repetitive or predictable patterns in data

Compression Categories

Lossless Compression

Perfect reconstruction of original data

Algorithms: Huffman Coding, LZW, Run-Length Encoding, Arithmetic Coding
Advantages: No data loss, perfect reconstruction
Applications: Text files, Executable files, Medical images
Disadvantages: Lower compression ratios
Lossy Compression

Approximate reconstruction with some data loss

Algorithms: JPEG, MP3, MPEG, H.264
Advantages: Higher compression ratios
Applications: Images, Audio, Video
Disadvantages: Quality degradation

📝 Exam Preparation Tips

Key Topics to Remember

  • • Understand lossless vs lossy compression
  • • Know Huffman coding algorithm steps
  • • Practice compression ratio calculations
  • • Remember LZW dictionary building process
  • • Understand compression applications in networking

Common Exam Questions

  • • "Build Huffman tree for given text" (8 marks)
  • • "Calculate compression ratio" (3 marks)
  • • "Explain LZW encoding steps" (6 marks)
  • • "Compare lossless vs lossy compression" (5 marks)
  • • "Applications of compression in networks" (4 marks)