Abstract

Carrier resilience is a typical business requirement. IPv4 deployments have traditionally solved this challenge through private internal site addressing in combination with separate NAT engines attached to multiple redundant carriers. IPv6 brings support for true end-to-end connectivity on the Internet, and hence NAT is the least desirable option in such deployments. Native IPv6 solutions for carrier resiliency, however, have drawbacks. This document discusses all currently-available options to organize carrier resiliency for a site, their strengths and weaknesses, and provides a history of past IETF efforts approaching the issue. The views presented here are the summary of discussions on the v6ops mailing list and are not just the personal opinion of the authors.