Eu teria que adivinhar: S é um IP pegajoso.
É um cruzamento entre IP dinâmico e IP estático, um IP fixo é atribuído dinamicamente, mas fica pendurado em seu modem de banda larga, desde que você não precise redefini-lo.
What most cable poviders will use is what is called A sticky dynamic IP address or sticky IP is an informal term used by cable and DSL Internet access subscribers to describe a dynamically assigned IP address that does not change often. The addresses are usually assigned with the DHCP protocol. Since the modems are usually powered-on for extended periods of time, the address leases are usually set to long periods and simply renewed upon expiration. If a modem is turned off and powered up again before the next expiration of the address lease, it will most likely receive the same IP address.DSLReports