A set of globally-reachable attachment registers is provided for interconnected communications networks and hosts. At least some of the networks and hosts each has a corresponding attachment register. The attachment registers are not located with their respective network or host. Information is stored in the attachment registers that establishes one or more logical links between the attachment registers. The information in certain ones of the attachment registers is used to perform one or more network communication functions. Non-limiting example functions include location registration and update, name to global locator resolution, routing, multi-homing, dynamic ISP selection, and handover.