When wells run dry: the 2020 IPv4 address market

With the recent IPv4 address exhaustion, many networks can no longer rely on requesting additional IPv4 addresses space. They resort to new ways to obtain addresses: buying and leasing. In this paper, we first shed light on the recent economic trends of the IPv4 buying market by augmenting transfer statistics with public and private pricing information from four large IPv4 brokers. We infer the size of the IPv4 leasing market through two different data sources: routing information observed from BGP collectors and RDAP databases operated by the Regional Internet Registries. We find that neither of those sources alone is capable of estimating the full market size. We relate our findings to discussions with 13 IPv4 brokers and summarize how networks handle their demand for obtaining IPv4 addresses in 2020.