Patent ID: 8400992

Claim:
A call setup method, adaptable to a mobile virtual private network (MVPN), wherein the mobile virtual private network (MVPN) comprises a plurality of access point apparatuses, at least one database, and a plurality of users, the database records a private extension number, a user phone number, and a user identity module of each of the users and a link address of the corresponding access point apparatus, and the users comprise a mobile origination (MO) user and a mobile termination (MT) user, the call setup method comprising: receiving a call setup request message for setting up a call with the mobile termination (MT) user from the mobile origination (MO) user by using the access point apparatus corresponding to the mobile origination (MO) user; updating the link address of the access point apparatus corresponding to the mobile origination (MO) user in the database by using the access point apparatus corresponding to the mobile origination (MO) user; connecting to a public land mobile network (PLMN) by using the access point apparatus corresponding to the mobile origination (MO) user, and recording a user phone number of the mobile origination (MO) user and a user phone number of the mobile termination (MT) user; setting up the call through the public land mobile network (PLMN) by using the mobile origination (MO) user and the mobile termination (MT) user; if the access point apparatus corresponding to the mobile origination (MO) user receives the call setup request message from the public land mobile network (PLMN), determining whether the received user phone number of the mobile origination (MO) user and the received user phone number of the mobile termination (MT) user are the same as the recorded user phone number of the mobile origination (MO) user and the recorded user phone number of the mobile termination (MT) user; and if the received user phone number of the mobile origination (MO) user and the received user phone number of the mobile termination (MT) user are the same as the recorded user phone number of the mobile origination (MO) user and the recorded user phone number of the mobile termination (MT) user, cancelling the call set up through the public land mobile network (PLMN), and setting up the call through the access point apparatus corresponding to the mobile origination (MO) user and the access point apparatus corresponding to the mobile termination (MT) user by using the mobile origination (MO) user and the mobile termination (MT) user.