ePDG (Evolved Packet Data Gateway), a vital role in VoWiFi (Wi-Fi Calling), allows users to connect to the mobile network via Wi-Fi hotspots, enjoy high-definition audio and video call, and seamlessly switch between VoLTE.
Click here to discover more about VoWiFi in our previous blog.
In VoWiFi, ePDG enables mobile operators to securely connect untrusted non-3GPP IP access networks to trusted E-UTRAN/EPC networks. Acting as a security gateway, it establishes IPSec tunnels to protect communications between Wi-Fi devices and operators' EPCs, using information from the 3GPP AAA process. ePDG interacts with Wi-Fi AP, AAA, and PGW via the SWu, SWm, and S2b interfaces, respectively. By bridging Wi-Fi access points and mobile networks, ePDG helps expand wireless coverage and offload traffic from congested cellular networks.
Notes
· AAA (Authentication, Authorization, and Accounting): Ensures secure access and manages user identities.
· HSS (Home Subscriber Server): A central database storing user profiles and authentication data.
· PGW: Connects the EPC to external IP networks, such as the Internet.
