key <string> {
	algorithm <string>;
	secret <string>;
}; // may occur multiple times

options {
	default-key <string>;
	default-port <integer>;
	default-server <string>;
	default-source-address ( <ipv4_address> | * );
	default-source-address-v6 ( <ipv6_address> | * );
};

server <string> {
	addresses { ( <quoted_string> [ port <integer> ] | <ipv4_address> [ port <integer> ] | <ipv6_address> [ port <integer> ] ); ... };
	key <string>;
	port <integer>;
	source-address ( <ipv4_address> | * );
	source-address-v6 ( <ipv6_address> | * );
}; // may occur multiple times