SAC079 - SSAC Advisory on the Changing Nature of IPv4 Address Semantics


In this advisory, the SSAC considers the changing role of Internet Protocol Version 4 (IPv4) addresses caused by the increasing scarcity, and subsequent exhaustion, of IPv4 addresses. The exhaustion of the IPv4 address supply has been predicted since the end of the 1980s. However, the large scale adoption of mobile devices and their associated IPv4 addressing needs accelerated the exhaustion timetable, and placed increased pressure on network operators to conserve IPv4 addresses. This pressure has resulted in a marked increase in the use of Network Address Translation (NAT) technologies, altering the attributability characteristics of IPv4 addresses, and requiring changes to their interpretation by parties wishing to use them as endpoint identifiers.