Local Service

Description

Local Service is a concept in 3GPP that refers to services provided by the current roamed-to network (i.e., the visited network) that are not Home Environment (HE) services. In other words, when a user is roaming, the visited network may offer additional services that are not part of the user's home subscription. These services are called local services. The same service can be provided by a network as a local service to inbound roamers and as an HE service to its own subscribers. This distinction is important for service provisioning, charging, and policy control.

The concept of Local Service was first introduced in 3GPP Release 99 (R99) and has evolved over time. In R99, a local service was defined as a service that can be exclusively provided in the current serving network by a Value Added Service Provider. This definition emphasized the exclusivity of the service to the serving network. However, starting from Release 5, the definition was changed to its current form: services provided by the current roamed-to network that are not HE services. This change reflected the growing need to support a wider range of services in roaming scenarios and to clarify the relationship between local services and home services.

Architecturally, local services are enabled by various network elements in the visited network, such as the Serving GPRS Support Node (SGSN), Gateway GPRS Support Node (GGSN), and application servers. The visited network may have agreements with the home network to allow inbound roamers to access these services. The home network may also provide information to the visited network about the subscriber's preferences and policies regarding local services. The UE may discover local services through broadcast information, ANDSF policies, or other means. The use of local services is typically subject to charging and policy control, and the visited network may apply different tariffs for local services compared to home services.

Local services can include a wide range of offerings, such as local information services (e.g., weather, news, traffic), local content (e.g., video on demand), local communication services (e.g., push-to-talk), and local value-added services (e.g., location-based services). These services can be provided by the visited network operator or by third-party service providers. The key characteristic is that they are not part of the user's home subscription and are only available while roaming in the visited network. The same service may be offered as an HE service to the visited network's own subscribers, highlighting the dual role of the network.

The evolution of Local Service has been marked by changes in definition and scope. The R99 definition focused on exclusivity, while the Rel-5 definition broadened the concept to include any service not provided by the HE. This change was motivated by the need to support new business models and to enable visited networks to offer differentiated services to roamers. In later releases, the definition has remained stable, but the underlying technologies and service delivery mechanisms have evolved. For example, with the advent of IMS, local services can be delivered via IMS, and with 5G, local services can be enabled through edge computing and network slicing. The concept of local services continues to be relevant in the context of roaming and service differentiation.

Purpose & Motivation

Local Service was created to address the need for visited networks to offer additional services to inbound roamers beyond what is provided by their home network. Prior to its introduction, roamers could only access services provided by their home network, limiting the ability of visited networks to differentiate their offerings and generate additional revenue. Local Service solves this by allowing visited networks to provide services that are not part of the home subscription, such as local information, content, and communication services. This enables new business models and improves the roaming experience. The change in definition from R99 to Rel-5 reflects the evolution from exclusive services to a broader concept that includes any service not provided by the HE. The motivation was to support a wider range of services and to clarify the relationship between local and home services.