Default destination block-list. The +1 allow-list covers the whole North American Numbering Plan, which
includes premium-rate exchanges (900, 976) and a set of Caribbean countries that share country code 1 but
are international calls with international rates — the classic toll-fraud / "one-ring" destinations. They are
blocked by default. Territories of the United States (+1340 USVI, +1670 Northern Marianas, +1671 Guam,
+1684 American Samoa, +1787/+1939 Puerto Rico) bill as domestic calls and are deliberately NOT blocked.
Operators can replace the whole list via telephony.outbound.blockedPrefixes, and should additionally enable
the carrier's own geographic permissions (see DEPLOYMENT.md) — this list is a backstop, not the only control.
Default destination block-list. The
+1allow-list covers the whole North American Numbering Plan, which includes premium-rate exchanges (900, 976) and a set of Caribbean countries that share country code 1 but are international calls with international rates — the classic toll-fraud / "one-ring" destinations. They are blocked by default. Territories of the United States (+1340 USVI, +1670 Northern Marianas, +1671 Guam, +1684 American Samoa, +1787/+1939 Puerto Rico) bill as domestic calls and are deliberately NOT blocked.Operators can replace the whole list via
telephony.outbound.blockedPrefixes, and should additionally enable the carrier's own geographic permissions (see DEPLOYMENT.md) — this list is a backstop, not the only control.