ppt

1. Data Compression in Application
Layer
Computer Networks Presentation

2. What is Data Compression?
• Data compression reduces the size of data to
save bandwidth and speed up transmission.
• It helps in efficient communication over
networks.

3. Why is Compression Needed?
• - Faster transmission
• - Saves bandwidth
• - Reduces storage
• - Optimizes app performance (email, web, file
transfer)

4. Types of Compression
• 1. Lossless Compression:
• - No data lost
• - Examples: ZIP, PNG
• 2. Lossy Compression:
• - Some data removed (for better size)
• - Examples: JPEG, MP3, MP4

5. How Does It Work?
• Common Techniques:
• - Run-Length Encoding (RLE)
• - Huffman Coding
• - LZW (Lempel-Ziv-Welch)
• Each method reduces repeated or common
data patterns.

6. Real-World Examples
• - Web pages use GZIP
• - Email attachments as ZIP files
• - Video streaming with MP4
• - FTP file transfers
• - Cloud storage compression

7. Advantages & Limitations
• ✅ Advantages:
• - Smaller file sizes
• - Faster data transfer
• - Saves data and bandwidth
• ⚠️Limitations:
• - May take time to compress/decompress
• - Lossy compression may reduce quality

8. Role in Application Layer
• - Used in HTTP (web), FTP, SMTP (email),
Telnet/SSH
• - Makes communication faster and more
efficient
• - Important for sending large data over the
internet