A Recommendation for IPv6 Address Text Representation

As IPv6 network grows, there will be more engineers and also non- engineers who will have the need to use an IPv6 address in text. While the IPv6 address architecture RFC 4291 section 2.2 depicts a flexible model for text representation of an IPv6 address, this flexibility has been causing problems for operators, system engineers, and users. This document will describe the problems that a flexible text representation has been causing. This document also recommends a canonical representation format that best avoids confusion. It is expected that the canonical format is followed by humans and systems when representing IPv6 addresses as text, but all implementations must accept and be able to handle any legitimate RFC4291 format.