Methods and apparatuses for capillary network device registration implemented in a wireless transmit/receive unit (WTRU) are disclosed. Registration or bootstrap messages may be received by a capillary network device where the WTRU acts as a gateway for communication between the capillary device and a network such as a 3GPP network. A capillary network device identifier (CNDID) is sent to the capillary device. A packet data protocol (PDP) context or PDN connection may be established with the network and the CNDID may be sent to a machine type communications (MTC) server. The WTRU may create the registration message, establish a connection with the network, and forward the registration message to the MTC server. Methods and apparatuses implemented in a network are also disclosed for identifying, addressing, and triggering the capillary devices from the MTC server. The trigger message may include fields for group communication, reducing signaling, and enabling charging.