CPC H04W 36/0022 (2013.01) [H04L 65/1016 (2013.01); H04W 36/14 (2013.01); H04W 48/18 (2013.01); H04W 76/12 (2018.02); H04W 76/18 (2018.02)] | 17 Claims |
1. A method for IP Multimedia Core Network Subsystem (IMS) Packet Data Network (PDN) recovery, the method comprising:
receiving, at a system, from a user equipment, at least one of an attach request with default Internet Access Point Name (APN) or a PDN disconnect request with IMS APN;
initiating, by the system, upon receiving the at least one of the attach request with default Internet APN or the PDN disconnect request with IMS APN, a timer for a finite period of time;
detecting, by the system, upon expiration of the timer, absence of a PDN connectivity request with IMS APN from the user equipment;
checking whether voice services are provided over a Wi-Fi network and the IMS APN is present in the Wi-Fi network;
transmitting, by the system, a detach request with re-attach required, to the user equipment based on the checking in an event of absence of an IMS bearer between the user equipment and the system;
receiving, by the system, a detach accept message from the user equipment, in response to the detach request; and
recovering, by the system, the IMS PDN connection by receiving an initial attach request and a PDN connectivity request with IMS PDN from the user equipment.
|