@misc{rfc8638,
    series =    {Request for Comments},
    number =    8638,
    howpublished =  {RFC 8638},
    publisher = {RFC Editor},
    doi =       {10.17487/RFC8638},
    url =       {https://www.rfc-editor.org/info/rfc8638},
    author =    {Mingwei Xu and Yong Cui and Jianping Wu and Shu Yang and Chris Metz},
    title =     {{IPv4 Multicast over an IPv6 Multicast in Softwire Mesh Networks}},
    pagetotal = 19,
    year =      2019,
    month =     sep,
    abstract =  {During the transition to IPv6, there are scenarios where a backbone network internally running one IP address family (referred to as the internal IP or I-IP family) connects client networks running another IP address family (referred to as the external IP or E-IP family). In such cases, the I-IP backbone needs to offer both unicast and multicast transit services to the client E-IP networks. This document describes a mechanism for supporting multicast across backbone networks where the I-IP and E-IP protocol families differ. The document focuses on the IPv4-over-IPv6 scenario, due to lack of real-world use cases for the IPv6-over-IPv4 scenario.},
}