S Mufti, R Piscopo, S Seward, Z Jahangir - US Patent 10,244,005, 2019 - Google Patents
A system and method that allows a mobile device to register for IMS services while the mobile device is roaming in a visited telecommunications network is disclosed. The sys tem …
RA Mann, LC Yeung - US Patent 8,971,215, 2015 - Google Patents
BACKGROUND As the demand increases for varying types of applications within mobile telecommunications networks, service provid ers must constantly upgrade their systems in …