Ericsson, AT&T and MediaTek completed North America’s first in-field trial of Layer 1/Layer 2 Triggered Mobility (LTM), a 5G Advanced capability designed to reduce data interruption as mobile devices move between cells. The companies tested Ericsson Low-Latency Mobility on AT&T’s commercial network using Ericsson Radio Access Network (RAN) technology and a MediaTek device platform. The trial measured up to a 25% reduction in data interruption during cell changes compared with legacy Layer 3 mobility procedures.
LTM moves parts of the mobility decision and execution process closer to Layers 1 and 2 of the radio protocol stack, reducing dependence on slower Layer 3 signaling procedures during handovers. Ericsson offers the capability through its 5G Advanced Critical IoT subscription. The companies said shorter interruption times and more deterministic mobility could improve performance for XR/VR, immersive video conferencing, cloud applications, time-critical communications, industrial automation, connected vehicles, and other services that require predictable latency and continuous data exchange.
Ericsson said it contributed to the development and standardization of LTM within 3GPP. The trial also positions LTM as a foundation for future AI-assisted mobility capabilities because edge-assisted perception, physical AI, real-time XR processing, and connected vehicle analytics depend on maintaining low-jitter links between devices, edge infrastructure, and cloud platforms while users and machines move across radio cells.ChatGP
• First North American in-field trial of Ericsson Low-Latency Mobility supporting L1/L2 Triggered Mobility.
• AT&T provided the live mobile network environment using Ericsson RAN technology, while MediaTek participated with the device platform.
• LTM reduced data interruption during cell changes by up to 25% compared with legacy Layer 3 mobility procedures in the trial.
• The feature shifts mobility execution closer to Layers 1 and 2 to shorten handover interruption times.
• Ericsson includes Low-Latency Mobility in its 5G Advanced Critical IoT subscription.
• Target applications include XR/VR, physical AI, industrial automation, immersive video conferencing, connected vehicles, cloud applications, and latency-critical IoT services.
• Ericsson contributed to LTM development and standardization within 3GPP.
“This milestone shows how 5G Advanced can translate into a better user experience with truly seamless connectivity needed for extended reality and physical AI,” said Mårten Lerner, Head of Networks Strategy & Product Management at Ericsson. “Together with AT&T and MediaTek, we’re demonstrating how smoother mobility can help deliver more responsive and reliable services for people and industries that depend on connectivity every moment they are on the move.”
🌐 Analysis: LTM addresses a fundamental limitation in mobile network architecture: the interruption and signaling overhead associated with transferring an active connection between cells. As operators deploy 5G Advanced capabilities, improvements in handover latency and determinism could become increasingly important for distributed AI inference, edge computing, industrial control, XR, and connected vehicle workloads that require continuous interaction between devices, RAN infrastructure, edge compute, and cloud platforms.
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| Technology Profile: Layer 1/Layer 2 Triggered Mobility (LTM) | |
| Standards Body | 3GPP |
| 3GPP Release | Release 18 — the first 5G-Advanced standards release |
| Primary Objective | Reduce service interruption and signaling latency when a connected device moves between radio cells. |
| Traditional Mobility | Layer 3 Triggered UE measurements → measurement report → network handover decision → RRC signaling → target cell access. |
| LTM Architecture | Lower-Layer Triggering The network preconfigures candidate target cells and mobility conditions, allowing Layer 1/Layer 2 measurements and signaling to initiate mobility execution. |
| Network Preparation | The serving gNB prepares multiple candidate cells and provides mobility configuration to the UE before the mobility event occurs. |
| Trigger Mechanism | Radio measurements and signaling at Layer 1 and Layer 2 can trigger execution without waiting for the full conventional Layer 3 measurement-reporting sequence. |
| Key Benefit | Shorter handover interruption time, improved mobility reliability, and more consistent data rates while devices move between cells. |
| Where It Matters | XR/VR Physical AI Connected Vehicles Industrial IoT Edge AI |
| Evolution Path | LTM establishes a lower-latency mobility framework that can support further enhancements to mobility reliability, multi-cell operation, and AI-assisted network optimization in later 5G-Advanced releases. |
| Architecture Significance | Mobility decisions traditionally depend heavily on Layer 3 signaling. LTM moves time-sensitive mobility triggering closer to the radio and MAC layers, shortening the control loop between changing radio conditions and mobility execution. |