US 12,294,928 B2
Method for improved handling of IP multimedia subsystem calls in a home mobile communication network and a visited mobile communication network
Mari Melander, Bonn (DE)
Assigned to DEUTSCHE TELEKOM AG, Bonn (DE)
Appl. No. 17/255,442
Filed by Deutsche Telekom AG, Bonn (DE)
PCT Filed Jul. 3, 2019, PCT No. PCT/EP2019/067879
§ 371(c)(1), (2) Date Dec. 23, 2020,
PCT Pub. No. WO2020/007929, PCT Pub. Date Jan. 9, 2020.
Claims priority of application No. 18181382 (EP), filed on Jul. 3, 2018.
Prior Publication US 2021/0258763 A1, Aug. 19, 2021
Int. Cl. H04W 4/90 (2018.01); H04L 65/1016 (2022.01); H04L 65/1069 (2022.01); H04W 76/50 (2018.01)
CPC H04W 4/90 (2018.02) [H04L 65/1016 (2013.01); H04L 65/1069 (2013.01); H04W 76/50 (2018.02)] 13 Claims
OG exemplary drawing
 
1. A method for handling of IP multimedia subsystem calls and configuration of a user equipment, wherein the method comprises:
roaming, by the user equipment, to a visited mobile communication network, wherein the user equipment comprises previously stored IP multimedia subsystem call-related parameters from a home mobile communication network;
receiving, by the user equipment, IP multimedia subsystem call parameter information from the visited mobile communication network, wherein the user equipment is connected to the visited mobile communication network via a radio access network associated with the visited mobile communication network, wherein the IP multimedia subsystem call parameter information comprises parameter information that is adjusted to the visited mobile communication network, and wherein the visited mobile communication network modifies the previously stored IP multimedia subsystem call-related parameters from the home mobile communication network via the IP multimedia subsystem call parameter information; and
attempting, by the user equipment, to connect to an IP multimedia subsystem locally via the visited mobile communication network and to place an IP multimedia subsystem call, wherein upon attempting to connect to the IP multimedia subsystem and to place the IP multimedia subsystem call, the user equipment utilizes the content of the IP multimedia subsystem call parameter information rather than utilizing the previously stored IP multimedia subsystem call-related parameters;
wherein the visited mobile communication network modifies one or more GSMA PRD IR.92 Table C.3.1 parameters of the user equipment;
wherein the previously stored IP multimedia subsystem call-related parameters comprises previously stored IP multimedia subsystem emergency call-related parameters;
wherein the IP multimedia subsystem call parameter information comprises IP multimedia subsystem emergency call parameter information; and
wherein the IP multimedia subsystem call is an IP multimedia subsystem emergency call.