Patent ID: 8682322

Claim:
A method, comprising: presenting a network node as a Visited Location Resource (VLR) for User Equipment (UE) to Mobile Management Entity (MME) in a Long Term Evolution (LTE) system, the network node includes an SGs interface to the MME in the LTE system and a MAP interface to a Mobile Switching Center (MSC) in a Cellular System (CS); receiving, at the MME, a notification of the UE registering the LTE system; registering, through the MAP interface, with a Home Location Resource (HLR) in the CS as the VLR for the UE; receiving a request for a routing number for the UE from the CS in connection with a mobile terminating call; transmitting, through the LTE system, a request for the UE to fall back to CS; receiving an indication from the HLR that the UE is being served by an MSC/VLR in the CS; transmitting a request for the routing number for the UE to the MSC/VLR; and in response to receiving the routing number from the MSC/VLR, transmitting a response to the routing-number request including the received routing number.