11. A multi-radio access technology (multi-RAT) wireless transmitter/receiver unit (WTRU), comprising:a processor configured to:
configure a primary radio connection of a RAT of a first type associated with a single core network control plane connection of the RAT of the first type,
configure a secondary radio connection of the RAT of the second type based on configuration information of the RAT of the second type, and
determine that a radio link failure (RLF) has occurred on the RAT of the second type; and
a wireless transmit/receive unit configured to:
receive, via the primary radio connection, the configuration information to configure the secondary radio connection of the RAT of the second type,
receive control information related to the RAT of the second type using the primary radio connection, and
transmit a message using resources of the RAT of the first type based on the determined RLF.