A multiple network connection method that includes: receiving, by a first device from a second device, capability information of the second device; transmitting, by the first device to the second device, a registration complete message indicating that the second device is registered to a network; and performing, by the first device, a service control for providing a service for the second device. A first connection path and a second connection path are established using the capability information. The first connection path is established between the network and the second device through the first device, and is used for conveying control information for the service. The second connection path is established between the network and the second device not through the first device, and is used for conveying user data for the service.