Contents

• Contents
• Introduction
• Separation Of Link Layer Functions
• Previous Protocols - AX.25
  • Frame Structure
  • Bit Stuffing
  • Packet Radio Media Access Protocols
  • TNC - Terminal Node Controller
  • AX.25 - Why Not Suitable
• DUAL - An Unreliable Amateur Link Format
• AX.25 vs. DUAL
• The DUAL Packet Format
  • Protocol Identification
  • Address Type
  • Source And Destination Addresses
  • Data
  • Checksum
  • Comments
• Protocol Ids
• Transporting IP Over DUAL - PR_IP
  • Addresses For IP
  • Broadcast Addresses
  • The CRC Field
  • Limitations And Disadvantages Of TCP/IP Over DUAL
  • Example IP Packets Over DUAL
• Transporting Compressed IP Over DUAL - PR_CIP
  • Protocol Identification
  • Addresses
• Broadcasting With DUAL
  • Broadcasting Link Addresses - PR_BCAST/AD_CALL
    • AD_CALL
  • Broadcasting Textual Information - PR_BCAST/AD_BEACON
    • AD_BEACON
  • Callsign Policy
• DUAL Implementation
  • Implementation Overview
  • Implementing DUAL In The 4.x BSD Network Stack
  • The Compression Algorithm
    • Why Compression Is Desirable
    • The Basic Idea
    • The Ugly Details
    • Compressed Packet Format
  • Modifications To The Compression Algorithm
• Conclusion
• Further Work
• The KISS TNC: A Simple Communications Protocol
  • Asynchronous Frame Format
  • Control Of The KISS TNC
  • Using DUAL With KISS Modems
• Installation Guide
  • Introduction
  • Installing The Code
  • Building The Code
  • Rebuilding The Kernel
• References
• About this document ...