As operators scale 5G-Advanced in 2026, the “Indoor Gap” remains a critical challenge due to high-frequency signal attenuation. To maintain voice service continuity, a Converged IMS (IP Multimedia Subsystem) serves as the essential service anchor. By integrating VoWiFi (Voice over Wi-Fi) via N3IWF or ePDG interfaces, the core network can treat any Wi-Fi access point as a micro-cell. This architecture enables seamless, “zero-drop” handovers between 5G NR and non-3GPP networks. IPLOOK focuses on this multi-access interworking, ensuring that session persistence and security remain consistent regardless of the radio environment, effectively reducing subscriber churn caused by indoor blind spots.
5G is incredibly fast, but physics is stubborn. High-frequency bands (like mmWave or even mid-band) struggle to penetrate thick concrete and modern glass. For a user, a 5G connection that drops the moment they walk into a basement or a home office isn’t “advanced”—it’s frustrating.
This is why we’re seeing a massive comeback for VoWiFi. It’s no longer just a “nice-to-have” backup; it’s a strategic layer of the 5G-A network.
How the “Invisible Handover” Works: The magic happens when the IMS Core acts as the universal anchor. It doesn’t care if you are on a 5G tower or a home router. By using a secure IPsec tunnel through the N3IWF (for 5G Core) or ePDG (for 4G/LTE), the call stays alive as you move.
The goal for 2026 isn’t just to provide coverage; it’s to make the transition between cellular and Wi-Fi completely invisible. If a subscriber has to check their signal bars before making a call, the network architecture hasn’t done its job.
At IPLOOK, our approach is simple: Consistency over Complexity. We spend our R&D cycles ensuring that the interworking between our 5G Core and Converged IMS is rock-solid. We believe that stability shouldn’t be a luxury dictated by your building’s architecture. By bridging the indoor gap with VoWiFi, we help operators build a resilient voice layer that simply works—anywhere.
Is indoor coverage still the “weak link” in your 5G strategy? Let’s talk about the practical hurdles of IMS integration in the comments.
