There is an increasing economic desire driven by widespread applications like IPTV or conferencing that a next generation Internet will grant transparent group communication service to all its stationary and mobile users. In this paper, we present a generic approach to inter-domain multicast, which is guided by an abstract, DHT-inspired overlay, but may operate on a future Internet architecture. It is based on the assumptions of a globally available end-to-end unicast routing between resolvable locators, taken from a name space that allows for aggregation. Our protocol design accounts for this aggregation, leading to forward path forwarding along bidirectional shared distribution trees in prefix space. The scheme facilitates multipath multicast transport, offers fault-tolerant routing, arbitrary redundancy for packets and paths and remains mobility agnostic. We present its applicability to IPv6, and evaluate signaling costs analytically based on its k-ary tree structure.