Nested Buddy System: A New Block Address Allocation Scheme for ISPs and IaaS Providers

We propose a novel block address allocation method, called the nested buddy system, which can make use of wasted areas in the classical buddy system due to internal fragmentation. While achieving high utilization of address space, our new scheme supports efficient address matching for routers in packet forwarding and for network middleboxes in packet filtering. Specifically, the scheme uses just one prefix rule for each allocated address block in a packet routing/filtering table. We show by analysis and simulation that the increased address utilization can lead to significant reduction in the probability of a denial-of-service under bursty address allocation requests. In contrast, the classical buddy system requires the aggregation of many requests over time to smooth out demand, resulting in service delays undesirable to end users. Our solution is applicable to ISPs in serving mobile users carrying many network connected IoT devices and IasS providers in the cloud in serving tenants with dynamically varying demands for network addresses.