Definition: Direct-to-Device (D2D) satellite-cellular convergence enables everyday consumer devices – such as smartphones, IoT devices, and vehicles – to connect directly to satellites for voice, messaging, and data services, eliminating the need for specialized satellite phones or ground-based infrastructure.

D2D in Non-Terrestrial Networks (NTN) explained

In Non-Terrestrial Networks (NTN), Direct-to-Device (D2D) calls enable direct communication between 4G, 5G devices and satellites in low earth orbit (LEO) without the need of special satellite phones. This approach is particularly valuable in remote or disaster-stricken areas, where conventional networks may be unavailable or overloaded.

D2D calls in NTN are not only used for voice communication but also support a wide range of applications, from emergency response and IoT connectivity to military and maritime operations. By leveraging the unique capabilities of NTN, these calls provide a robust and flexible alternative to terrestrial networks, ensuring connectivity even in the most challenging environments.

Lawful Interception: Challenges and Solutions

Satellite and mobile operators providing D2D services must comply with the same lawful interception requirements as terrestrial networks. This includes enabling law enforcement agencies (LEAs) to intercept communications when legally authorized, just as they do with traditional mobile networks. 

The technical architecture for lawful interception in D2D and satellite networks is designed to ensure that intercepted data can be delivered to LEAs in a standardized format. This includes the ability to intercept both content and metadata. Standards bodies like ETSI and 3GPP are actively working on integrating these capabilities into both terrestrial and non-terrestrial networks.