UAS Application Specific Server

Description

The UAS Application Specific Server (UASS) is a functional entity defined within the 3GPP architecture to support Uncrewed Aerial System (UAS) services. It acts as an application server that interfaces with the 3GPP core network (specifically the Service Capability Exposure Function - SCEF or Network Exposure Function - NEF) and external UAS Service Suppliers (USS) or UAS Traffic Management (UTM) systems. The UASS provides a standardized interface for UAS-specific application functions, enabling the secure and efficient delivery of services to UAVs and their controllers.

Architecturally, the UASS is part of the service layer and is defined in the context of the 3GPP system's support for UAS. It communicates with the 3GPP core network via reference points, such as N33 (between NEF and UASS) as specified in TS 29.257. This allows the UASS to request network services (e.g., location reporting, QoS management, event monitoring) for UAVs and to receive relevant network exposure information. The UASS itself may host application logic for services like UAS identification, geo-fencing, flight path management, and contingency handling.

Its role is to abstract UAS application needs into network service requests. For example, a UASS can subscribe to location reporting events for a specific UAV from the network, process this data, and provide it to a USS for air traffic management. It handles the protocol conversion and session management required between the application world (UTM/USS) and the 3GPP network world. Key components involve the service logic, the interfaces to the 3GPP core (NEF/SCEF), and interfaces to external UAS systems, ensuring a secure and reliable service delivery framework for aerial vehicles.

Purpose & Motivation

The UASS was created to address the need for a standardized, network-integrated application server for UAS operations within 5G and beyond systems. Prior to its definition, UAS applications would have to interact with cellular networks in an ad-hoc, non-standardized manner, making integration complex and limiting the ability to leverage advanced network capabilities like precise location, low-latency communication, and network slicing for drone services.

Its introduction, starting in Release 17, was motivated by the growing regulatory and commercial push for UAS Traffic Management (UTM) systems. 3GPP networks are seen as a key enabler for Beyond Visual Line of Sight (BVLOS) drone operations, requiring reliable command & control and tracking. The UASS provides a defined architectural point where UAS application logic can reside, enabling standardized exposure of 3GPP network capabilities to UTM systems. This solves the problem of fragmented integration, allowing for scalable, secure, and efficient support of diverse UAS applications like package delivery, surveillance, and infrastructure inspection over mobile networks.