The IPv6 Company D-Link Systems, Inc. This document specifies the transition requirements for an IPv6 Customer Edge (CE) router, either provided by the service provider or thru the retail market. Specifically, this document extends the "Basic Requirements for IPv6 Customer Edge Routers" ([RFC7084]) in order to allow the provisioning of IPv6 transition services for the support of IPv4 as a Service (IPv4aaS) by means of new transition mechanisms, which where not available at the time [RFC7084] was published. The document only covers transition technologies for delivering IPv4 in IPv6-only access networks, commonly called IPv4 "as-a-service" (IPv4aaS), as required in a world where IPv4 addresses are no longer available, so hosts in the customer LANs with IPv4-only or IPv6-only applications or devices, requiring to communicate with IPv4-only services at the Internet, are still able to do so.