Global Virtual Network Service

Description

The Global Virtual Network Service (GVNS) is a comprehensive service architecture defined in 3GPP TS 29.163. It operates as a service layer framework designed to facilitate global service delivery by creating a virtualized, consistent network environment for subscribers. The architecture is built upon the IP Multimedia Subsystem (IMS) and leverages existing core network functions, but introduces service-level agreements (SLAs) and policies that are managed centrally to provide a uniform user experience. It essentially creates a 'virtual home network' for roaming users, masking the underlying visited network's specific configurations and capabilities.

At its core, GVNS works by establishing a set of standardized service profiles and policies that are recognized and enforced across participating operator networks. When a user roams, their service requests are intercepted and processed according to their GVNS profile, which is retrieved from their home network. This involves the coordination of Policy and Charging Control (PCC) functions, application functions, and potentially service capability exposure functions. The visited network's resources are allocated and configured to meet the SLA guarantees defined in the user's GVNS subscription, such as minimum bandwidth, latency, or access to specific IMS-based services like VoLTE.

Key components in the GVNS architecture include the GVNS Application Server, which hosts the service logic and user profiles, and the interaction with the PCC architecture (PCRF and PCEF) for dynamic policy enforcement. It also interfaces with charging systems to ensure accurate billing for the enhanced roaming services. The protocol specified in TS 29.163 defines the messages and procedures between the serving network's entities and the home GVNS platform. Its role is to decouple service delivery from physical network topology, enabling operators to offer premium, predictable roaming experiences and fostering global service interoperability beyond basic connectivity.

Purpose & Motivation

GVNS was created to address the challenges of inconsistent and often degraded service quality experienced by users while roaming internationally. Prior to its introduction, roaming services were largely limited to basic voice and data connectivity, with advanced services like high-definition voice (VoLTE), video calling, or guaranteed data rates frequently being unavailable or behaving unpredictably on visited networks. The service experience was dependent on bilateral agreements and the specific capabilities of the visited network, leading to a fragmented user experience.

The primary problem GVNS solves is the lack of service continuity and quality assurance for roaming subscribers. It allows operators to offer tiered service packages that guarantee certain performance levels (e.g., 'business class' data roaming) regardless of the subscriber's location. This was motivated by the growing demand for seamless mobile broadband experiences and the commercial need for operators to differentiate their offerings and create new revenue streams from roaming. By virtualizing the service layer, GVNS enables a 'home-like' experience abroad, which was a significant step beyond the legacy roaming frameworks that primarily handled authentication and basic call routing.

Key Features

• Global service continuity for IMS-based services
• Standardized service profiles and SLAs for roaming
• Integration with Policy and Charging Control (PCC) for dynamic resource management
• Support for both 3GPP and non-3GPP access networks
• Centralized service logic and user profile management
• Enhanced charging mechanisms for value-added roaming services

Evolution Across Releases

Defining Specifications