An inter-AS address space (re)allocation planning scheme in hierarchical and automatic number allocation

Due to the continuously expanding scale of the Internet and increasing demand for highly available networks, there is strong desire for provider-aggregatable (PA) addressing and the accompanying multi-address-based multihoming scheme, which can efficiently reduce the size of the global routing table in core routers and boost the availability of networks. The growing demands on PA addressing (e.g., address space allocation, renumbering) will require that network service providers (NSPs) put more efforts into addressing-related management tasks in the future. To relieve NSPs from the complex tasks and heavy burden of manual operation, in this paper we introduce an inter-autonomous system (inter-AS) address space (re)allocation planning scheme (ASAP) in the context of hierarchical automatic address number allocation (HANA). By introducing multiple functionalities, (i) chained request, (ii) defragmentation with the minimum renumbering overhead, and (iii) parallel Probe/Reservation processes, into HANA, HANA/ASAP offers NSPs an easy-to-use and powerful tool supporting inter-AS automated address space (re)allocation adjustment in a distributed manner. Simulations have been conducted to observe the effect of HANA/ASAP in PA from the aspects of address efficiency, address conservation, and renumbering overhead.