3. Address Delegation Recommendations
The IESG and the IAB recommend the allocations for the boundary
between the public and the private topology to follow those general
rules:
- /48 in the general case, except for very large subscribers.
- /64 when it is known that one and only one subnet is needed by
design.
- /128 when it is absolutely known that one and only one device
is connecting.
In particular, we recommend:
- Home network subscribers, connecting through on-demand or
always-on connections should receive a /48.
- Small and large enterprises should receive a /48.
- Very large subscribers could receive a /47 or slightly shorter
prefix, or multiple /48's.
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