Dan York

Are you a “content provider,” such as a website operator, seeking to understand how to ensure your content is available over IPv6?  If so, the IETF recently published an excellent guide in RFC 6589, “Considerations for Transitioning Content to IPv6“.  Written by Comcast’s Jason Livingood the document explains both the issues with moving content to IPv6 and offers suggestions for migration plans and implementation tactics.

From the introduction:

This document describes considerations for the transition of end-user content on the Internet to IPv6. While this is tailored to address end-user content, which is typically web-based, many aspects of this document may be more broadly applicable to the transition to IPv6 of other applications and services. The issues explored herein will be of particular interest to major web content sites (sometimes described hereinafter as “high-service-level domains”), which have specific and unique concerns related to maintaining a high-quality user experience for all of their users during their transition to IPv6. This document explores the challenges involved in the transition to IPv6, potential migration tactics, possible migration phases, and other considerations. Some sections of this document also include information about the potential implications of various migration tactics or phased approaches to the transition to IPv6.

The table of contents is as follows:

   1. Introduction ....................................................4
   2. Challenges When Transitioning Content to IPv6 ...................4
      2.1. IPv6-Related Impairment ....................................5
      2.2. Operational Maturity Concerns ..............................5
      2.3. Volume-Based Concerns ......................................5
   3. IPv6 Adoption Implications ......................................6
   4. Potential Migration Tactics .....................................6
      4.1. Solving Current End-User IPv6 Impairments ..................7
      4.2. Using IPv6-Specific Names ..................................8
      4.3. Implementing DNS Resolver Whitelisting .....................8
           4.3.1. How DNS Resolver Whitelisting Works ................11
           4.3.2. Similarities to Content Delivery Networks
                  and Global Server Load Balancing ...................15
           4.3.3. Similarities to DNS Load Balancing .................15
           4.3.4. Similarities to Split DNS ..........................15
           4.3.5. Related Considerations .............................16
      4.4. Implementing DNS Blacklisting .............................17
      4.5. Transitioning Directly to Native Dual Stack ...............18
   5. Potential Implementation Phases ................................19
      5.1. No Access to IPv6 Content .................................19
      5.2. Using IPv6-Specific Names .................................19
      5.3. Deploying DNS Resolver Whitelisting Using Manual
           Processes .................................................19
      5.4. Deploying DNS Resolver Whitelisting Using
           Automated Processes .......................................19
      5.5. Turning Off DNS Resolver Whitelisting .....................20
      5.6. Deploying DNS Blacklisting ................................20
      5.7. Fully Dual-Stack Content ..................................20
   6. Other Considerations ...........................................20
      6.1. Security Considerations ...................................20
      6.2. Privacy Considerations ....................................21
      6.3. Considerations with Poor IPv4 and Good IPv6 Transport .....22

The document is an excellent guide for content providers and anyone seeking to understand how to make their content available over IPv6.