RFC 8175 - Dynamic Link Exchange Protocol (DLEP)

• Status: Proposed Standard
• Published: June 2017
• Stream: IETF
• Errata: RFC 8175 Errata

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Document Information

• RFC Number: 8175
• Title: Dynamic Link Exchange Protocol (DLEP)
• Authors: S. Ratliff (VT iDirect), S. Jury (Cisco Systems), D. Satterwhite (Broadcom), R. Taylor (Airbus Defence & Space), B. Berry
• Date: June 2017
• Category: Standards Track
• ISSN: 2070-1721

Abstract

When routing devices rely on modems to effect communications over wireless links, they need timely and accurate knowledge of the characteristics of the link (speed, state, etc.) in order to make routing decisions. In mobile or other environments where these characteristics change frequently, manual configurations or the inference of state through routing or transport protocols does not allow the router to make the best decisions. This document introduces a new protocol called the Dynamic Link Exchange Protocol (DLEP), which provides a bidirectional, event-driven communication channel between the router and the modem to facilitate communication of changing link characteristics.

Status of This Memo

This is an Internet Standards Track document.

This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841.

Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc8175.

Copyright Notice

Copyright (c) 2017 IETF Trust and the persons identified as the document authors. All rights reserved.

This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents http://trustee.ietf.org/license-info in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.

Table of Contents

• 1. Introduction
• 2. Protocol Overview
  • 2.1. Destinations
  • 2.2. Conventions and Terminology
• 3. Requirements
• 4. Implementation Scenarios
• 5. Assumptions
• 6. Metrics
• 7. DLEP Session Flow
  • 7.1. Peer Discovery State
  • 7.2. Session Initialization State
  • 7.3. In-Session State
    • 7.3.1. Heartbeats
  • 7.4. Session Termination State
  • 7.5. Session Reset State
    • 7.5.1. Unexpected TCP Connection Termination
• 8. Transaction Model
• 9. Extensions
  • 9.1. Experiments
• 10. Scalability
• 11. DLEP Signal and Message Structure
  • 11.1. DLEP Signal Header
  • 11.2. DLEP Message Header
  • 11.3. DLEP Generic Data Item
• 12. DLEP Signals and Messages
  • 12.1. General Processing Rules
  • 12.2. Status Code Processing
  • 12.3. Peer Discovery Signal
  • 12.4. Peer Offer Signal
  • 12.5. Session Initialization Message
  • 12.6. Session Initialization Response Message
  • 12.7. Session Update Message
  • 12.8. Session Update Response Message
  • 12.9. Session Termination Message
  • 12.10. Session Termination Response Message
  • 12.11. Destination Up Message
  • 12.12. Destination Up Response Message
  • 12.13. Destination Announce Message
  • 12.14. Destination Announce Response Message
  • 12.15. Destination Down Message
  • 12.16. Destination Down Response Message
  • 12.17. Destination Update Message
  • 12.18. Link Characteristics Request Message
  • 12.19. Link Characteristics Response Message
  • 12.20. Heartbeat Message
• 13. DLEP Data Items
  • 13.1. Status
  • 13.2. IPv4 Connection Point
  • 13.3. IPv6 Connection Point
  • 13.4. Peer Type
  • 13.5. Heartbeat Interval
  • 13.6. Extensions Supported
  • 13.7. MAC Address
  • 13.8. IPv4 Address
    • 13.8.1. IPv4 Address Processing
  • 13.9. IPv6 Address
    • 13.9.1. IPv6 Address Processing
  • 13.10. IPv4 Attached Subnet
    • 13.10.1. IPv4 Attached Subnet Processing
  • 13.11. IPv6 Attached Subnet
    • 13.11.1. IPv6 Attached Subnet Processing
  • 13.12. Maximum Data Rate (Receive)
  • 13.13. Maximum Data Rate (Transmit)
  • 13.14. Current Data Rate (Receive)
  • 13.15. Current Data Rate (Transmit)
  • 13.16. Latency
  • 13.17. Resources
  • 13.18. Relative Link Quality (Receive)
  • 13.19. Relative Link Quality (Transmit)
  • 13.20. Maximum Transmission Unit (MTU)
• 14. Security Considerations
• 15. IANA Considerations
  • 15.1. Registrations
  • 15.2. Signal Type Registrations
  • 15.3. Message Type Registrations
  • 15.4. DLEP Data Item Registrations
  • 15.5. DLEP Status Code Registrations
  • 15.6. DLEP Extension Registrations
  • 15.7. DLEP IPv4 Connection Point Flags
  • 15.8. DLEP IPv6 Connection Point Flags
  • 15.9. DLEP Peer Type Flags
  • 15.10. DLEP IPv4 Address Flags
  • 15.11. DLEP IPv6 Address Flags
  • 15.12. DLEP IPv4 Attached Subnet Flags
  • 15.13. DLEP IPv6 Attached Subnet Flags
  • 15.14. DLEP Well-Known Port
  • 15.15. DLEP IPv4 Link-Local Multicast Address
  • 15.16. DLEP IPv6 Link-Local Multicast Address
• 16. References
  • 16.1. Normative References
  • 16.2. Informative References
• Acknowledgments
• Authors' Addresses

Appendices

• Appendix A. Discovery Signal Flows
• Appendix B. Peer-Level Message Flows
  • B.1. Session Initialization
  • B.2. Session Initialization - Refused
  • B.3. Router Changes IP Addresses
  • B.4. Modem Changes Session-Wide Metrics
  • B.5. Router Terminates Session
  • B.6. Modem Terminates Session
  • B.7. Session Heartbeats
  • B.8. Router Detects a Heartbeat Timeout
  • B.9. Modem Detects a Heartbeat Timeout
• Appendix C. Destination-Specific Message Flows
  • C.1. Common Destination Notification
  • C.2. Multicast Destination Notification
  • C.3. Link Characteristics Request

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Related Resources

• Official RFC: RFC 8175
• DataTracker: RFC 8175 Info
• Errata: RFC Editor Errata