Efficient signaling for machine type communication

A wireless transmit/control unit (WTRU), comprising:

• a receiver, the receiver configured at least to:
• receive a first message from a communication network, the first message including a first indication of a capability of the communication network for small data transfer capability, the small data transfer capability including the capability to send user data via a control plane;
• a processor, the processor configured at least to:
• append a second indication to a second message based at least in part on the first message, the second indication indicating a capability of the WTRU for the small data transfer capability;
• and
• a transmitter, the transmitter configured at least to:
• send the second message to the communication network, the receiver being further configured to:
• receive a third message from the communication network, the third message including a third indication, the third indication further indicating the capability of the communication network for the small data transfer, the processor being further configured to:
• append a fourth indication to a fourth message, the fourth indication indicating the presence of small data in the fourth message, the transmitter being further configured to:
• send the fourth message to the communication network, the fourth message including appended small data, the small data including user data, at least the user data being sent via the control plane.