Anycast is a new IPv6 function in which an anycast address can be assigned to multiple nodes that provide the same service. The Anycast packet is transmitted to one appropriate node selected out of all the nodes assigned to the same anycast address. Although it is expected that anycast will be used in various ways, the use of anycast is quite limited today. This is because anycast functionalities are still unclear, and it is difficult to realize a global anycast that requires existing routing protocols to be radically changed. In this paper, we clarify and classify some essential anycast issues and propose a new and practical communication architecture, based on Mobile IPv6 architecture, that overcomes the anycast difficulties.