http://www.rfc-editor.org/rfc/rfc6874.txt
RFC 6874: Representing IPv6 Zone Identifiers in Address Literals and Uniform Resource Identifiers, B. Carpenter, S. Cheshire, R. Hinden2013-02-01T23:00:00-00:00This document describes how the zone identifier of an IPv6 scoped address, defined as in the IPv6 Scoped Address Architecture (RFC 4007), can be represented in a literal IPv6 address and in a Uniform Resource Identifier that includes such a literal address. It updates the URI Generic Syntax specification (RFC 3986) accordingly.