APNIC makes portable allocations to organisations. All customer assignments and sub-allocations made from those allocations are non-portable and should be made on a lease basis. This means that if the end-user changes service providers they should return the space assigned to them by the ISP, obtain an assignment from the new ISP and renumber into that ISP's address block. For more information see section 11.4 of Policies for address space management in the Asia Pacific region.
Address ranges need to remain aggregated to protect the Internet routing system. Taking addresses from one ISP to another fragments address ranges, which leads to added pressure on the global routing tables. Therefore, when APNIC allocates a range of addresses, it is on the condition that the range remains aggregated and that customers are not allowed to "take" addresses away to other providers.
APNIC acknowledges that organisations changing ISPs will be inconvenienced by the need to renumber their networks, but these efforts are necessary to protect the health of the global network. Also, renumbering into a larger, aggregated address range is likely to provide the organisation with a more reliable connection to the Internet than maintaining a small, individually routed network.
