254  Ad Hoc DTN and Social Routing

254.1 Overview

This section covers Delay-Tolerant Networks (DTN) and social routing protocols for disconnected ad hoc scenarios. DTN enables communication in environments where traditional routing fails due to lack of continuous connectivity.

TipChapter Series

This topic is covered in four focused chapters:

  1. DTN Fundamentals and Store-Carry-Forward - Core DTN concepts, disconnected network challenges, and the store-carry-forward paradigm
  2. DTN Epidemic Routing - Flooding-based protocols, buffer management, and Spray-and-Wait optimization
  3. DTN Social Routing - Context-aware routing, utility functions, and SocialCast protocol
  4. DTN Applications - Real-world deployments including wildlife tracking, rural connectivity, and hybrid architectures

254.2 Learning Path

Start here if you’re new to DTN:

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flowchart LR
    A[DTN Fundamentals] --> B[Epidemic Routing]
    B --> C[Social Routing]
    C --> D[Applications]

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    style B fill:#16A085,stroke:#2C3E50,color:#fff
    style C fill:#E67E22,stroke:#16A085,color:#fff
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254.3 Quick Reference

Chapter Key Topics Difficulty
DTN Fundamentals Store-carry-forward, disconnected networks, DTN vs TCP/IP Intermediate
Epidemic Routing Message flooding, TTL, buffer management, Spray-and-Wait Intermediate
Social Routing Utility functions, SocialCast, bounded replication Advanced
Applications DakNet, ZebraNet, hybrid architectures, disaster recovery Intermediate

254.4 Prerequisites

Before starting this series, you should be familiar with:

254.5 Key Concepts Preview

Delay-Tolerant Networks address scenarios where:

  • No continuous end-to-end path exists
  • Nodes are mobile and encounters are opportunistic
  • Latency tolerance ranges from minutes to days
  • Traditional routing protocols fail completely

Core DTN Mechanisms:

  • Store: Buffer packets in local memory
  • Carry: Physically transport packets while moving
  • Forward: Transfer packets on opportunistic contacts

Routing Strategies:

  • Epidemic: Flood messages to all encountered nodes (95% delivery, 1000% overhead)
  • Context-Aware: Use utility functions for smart forwarding (88% delivery, 200% overhead)
  • SocialCast: Exploit social patterns with bounded replication (88% delivery, 200% overhead)

254.6 What’s Next

Start with DTN Fundamentals and Store-Carry-Forward to understand why traditional routing fails in disconnected networks and how DTN’s store-carry-forward paradigm enables communication.