Specifies the route option in router advertisements according to RFC 4191 (Route Information Option). The following settings are possible:
- Interface name
- Specifies the name of the logical interface to be used for sending router advertisements with this route option.
- Prefix
- Prefix of the route option, e.g."2001:db8::/32".
- Lifetime
- The duration in seconds for the route to remain valid.
- Route preference
- The preference of the route. Possible values are "high", "medium" (default) and "low".
