Internet Service Providers (ISPs) currently deploying the new IP protocol version follow the RIRs (Regional Internet Registries) politics about how to give out the enormous IPv6 addressing space among their clients.

There is a big difference between the recommendations to allocate IPv4 addresses, that hold about the economy of addresses, since addresses are a scare resource and should be managed with caution, and IPv6 ones, that hold about the flexibility.

RIPE RIRs are recommending to ISPs and operators that allocate to each IPv6 client a/48 subnetwork with the finality that clients can manage their own subnetworks without using NAT. (The idea is that NAT disappears in IPv6).