754 Transport Protocols: Comprehensive Review
Deep Dives:
- Transport Fundamentals - TCP/UDP basics
- Transport Optimizations - IoT adaptations
- DTLS Security - Secure datagram transport
Comparisons:
- MQTT Protocol - TCP-based messaging
- CoAP Protocol - UDP-based RESTful protocol
Network Layer:
- Networking Fundamentals - Network layer context
- IPv6 and 6LoWPAN - Network layer for IoT
Learning:
- Quizzes Hub - Test your transport knowledge
- Simulations Hub - TCP vs UDP comparisons
754.1 Overview
This comprehensive review consolidates transport layer knowledge for IoT applications. The content has been organized into focused chapters for easier navigation and study.
Estimated Total Time: 2 hours
754.2 Chapter Index
754.2.1 1. Protocol Selection and Trade-offs
Transport Review: Protocol Selection
- Key takeaways for UDP, TCP, and DTLS
- Selection criteria: reliability, latency, power, security
- Trade-off analysis: TCP retransmission vs UDP application-layer retry
- TCP vs UDP architecture comparison diagrams
Estimated Time: 30 minutes
754.2.2 2. Overhead and Battery Analysis
Transport Review: Overhead Analysis
- Protocol overhead visualization for 10-byte payloads
- Overhead comparison tables: UDP (24B), TCP (244B), DTLS (53B)
- Battery life calculations for environmental sensors
- Impact of transmission frequency on battery life
Estimated Time: 25 minutes
754.2.3 3. DTLS Security Architecture
Transport Review: DTLS Security
- DTLS architecture for securing UDP-based IoT communication
- DTLS handshake process and overhead
- Cookie-based DoS protection for constrained devices
- Session resumption for battery savings (68% reduction)
Estimated Time: 20 minutes
754.2.4 4. Knowledge Check
Transport Review: Knowledge Check
- Understanding checks for battery life impact and protocol selection
- Quiz questions on TCP vs UDP overhead
- DTLS handshake and session resumption questions
- Comprehensive review scenarios for protocol matching
Estimated Time: 45 minutes
754.3 Quick Reference
| Protocol | Header | Reliability | Best For |
|---|---|---|---|
| UDP | 8 bytes | Best effort | Real-time, telemetry |
| TCP | 20-60 bytes | Guaranteed | Firmware, critical data |
| DTLS | +29 bytes | Secured UDP | Secure CoAP |
754.4 Learning Path
Recommended order:
- Start with Protocol Selection for key concepts
- Study Overhead Analysis for battery calculations
- Review DTLS Security for security patterns
- Test knowledge with Knowledge Check
The Reality: TCP can actually be less reliable than UDP for battery-powered IoT devices. TCP’s extra energy cost causes sensors to die early, making them 100% unreliable (no data at all).
Real-World Example: Copenhagen parking sensors switched from TCP to UDP, improving battery life from 8.3 months to 41 months (5× improvement) and reducing battery replacement costs by 82%.
Key Insight: For battery-powered IoT, operational reliability (device stays alive) matters more than packet reliability (every packet arrives).
See Protocol Selection for the full analysis.
754.5 What’s Next
After completing this review:
- Topologies: Network structures and their trade-offs
- MQTT Protocol: Publish-subscribe messaging on TCP
- CoAP Protocol: RESTful communication over UDP