Roaming Value-Added Services

Description

Roaming Value-Added Services (RVAS) represent a framework within 3GPP standards, introduced in Release 19, to define and deliver enhanced services to subscribers while they are roaming. The architecture involves coordination between the visited Public Land Mobile Network (VPLMN) and the home Public Land Mobile Network (HPLMN) to ensure service continuity and quality. Key components include the Home Subscriber Server (HSS) or Unified Data Management (UDM) for subscriber profile management, the Policy Control Function (PCF) for dynamic policy enforcement, and the Service Capability Exposure Function (SCEF) or Network Exposure Function (NEF) for secure service exposure to third-party application providers. The framework leverages existing roaming interfaces and protocols, such as those defined in the Diameter-based S6a/S6d or HTTP-based Nudm/Npcf interfaces, to exchange service authorization, policy, and charging information.

Operationally, when a subscriber roams into a visited network, the HPLMN provides the VPLMN with the subscriber's RVAS profile, which details the subscribed value-added services and associated policies. The VPLMN then applies these policies to enable or prioritize specific services, ensuring the subscriber receives the same service experience as in their home network. This process involves dynamic policy control where the PCF in the home or visited network can adjust Quality of Service (QoS) parameters, such as bandwidth allocation and latency targets, based on real-time network conditions and service requirements. Charging and billing are handled through integrated online and offline charging systems (OCS/OFCS), with detailed records generated for settlement between operators.

The role of RVAS in the network is to bridge the gap between basic connectivity and premium service delivery in roaming scenarios. It addresses the technical challenges of maintaining service-level agreements (SLAs) across administrative boundaries, enabling features like guaranteed bit rates for video streaming, low-latency access for cloud gaming, and reliable connectivity for critical IoT applications. By standardizing these capabilities, 3GPP ensures interoperability between different operators' networks, fostering a global ecosystem where advanced services can be seamlessly offered to roaming users, thereby enhancing customer satisfaction and driving adoption of 5G and beyond services.

Purpose & Motivation

RVAS was created to address the growing demand for high-quality, value-added services while users are roaming, a scenario where service experience has historically been inconsistent or limited. Prior to its standardization, operators often relied on bilateral agreements and proprietary solutions to offer enhanced roaming services, leading to fragmentation, increased complexity, and limited scalability. This approach hindered the widespread availability of services like high-definition video streaming, real-time gaming, and enterprise IoT solutions for roaming subscribers, as technical and commercial interoperability was challenging.

The motivation for RVAS stems from the evolution of mobile networks towards 5G and the increasing importance of service differentiation. With the proliferation of data-intensive applications, operators sought to monetize roaming beyond basic voice and data access by offering tiered service packages. RVAS provides a standardized framework to define, authorize, and deliver these services, ensuring that subscribers receive a consistent experience regardless of their location. It solves problems related to policy enforcement across network boundaries, dynamic QoS management, and integrated charging, enabling operators to launch new revenue-generating services efficiently.

Historically, roaming focused primarily on core connectivity, with value-added services being an afterthought. RVAS represents a paradigm shift by embedding service capabilities into the roaming architecture from the outset. It addresses limitations of previous approaches, such as the lack of granular policy control and the inability to expose network capabilities to third-party service providers in a roaming context. By doing so, RVAS facilitates innovation, allowing operators and application providers to collaborate on delivering tailored experiences to roaming users, thereby enhancing the overall value proposition of mobile services.