- * systemd-networkd's [Network] section gained a new setting
- IPv6PDSubnetId= that allows explicit configuration of the preferred
- subnet that networkd's Prefix Delegation logic assigns to interfaces.
+ * systemd-networkd gained a new section [DHCPv6PrefixDelegation] which
+ controls delegated prefixes assigned by DHCPv6 client. The section
+ has three settings: SubnetID=, Assign=, and Token=. The setting
+ SubnetID= allows explicit configuration of the preferred subnet that
+ systemd-networkd's Prefix Delegation logic assigns to interfaces. If
+ Assign= is enabled (which is the default) an address from any acquired
+ delegated prefix is automatically chosen and assigned to the
+ interface. The setting Token= specifies an optional address generation
+ mode for Assign=.