Description
The Horizontal Coupling Plane (HCP) is a management architecture concept defined within the 3GPP framework for network slicing, specifically in the context of management and orchestration. It is not a physical interface but a logical plane that standardizes the interactions and information exchange between Management Services (MnS) that belong to different management domains. Typically, these domains are the Communication Service Customer (CSC) domain (e.g., an enterprise or vertical industry tenant) and the Communication Service Provider (CSP) domain (e.g., a mobile network operator). The HCP enables the CSC's management system to request, monitor, and manage the lifecycle of network slice instances that are provisioned within the CSP's network. Technically, the HCP is realized through a set of standardized Management Service Interfaces, often based on RESTful APIs defined using OpenAPI specifications. These interfaces allow for operations such as network slice template onboarding, network slice instance provisioning, activation, deactivation, termination, and performance monitoring reporting. The information models exchanged across the HCP include descriptors (like Network Slice Template) and runtime information (like Network Slice Instance identifiers and status). The HCP works in conjunction with the Vertical Coupling Plane (VCP), which handles management interactions within a single administrative domain (e.g., between the Network Slice Management Function (NSMF) and the Network Slice Subnet Management Function (NSSMF) within an operator). By providing this horizontal interface, the HCP decouples the tenant's operational and business support systems from the internal, potentially proprietary, management systems of the network operator, enabling multi-vendor and multi-domain slice management.
Purpose & Motivation
The HCP was created to address a fundamental challenge in the commercialization and operation of 5G network slicing: how can an external customer (tenant) seamlessly manage their dedicated slice resources without direct access to the operator's internal network management systems? Prior to its definition, management interactions between customers and providers were ad-hoc, proprietary, and not scalable for a future with potentially thousands of slices for diverse vertical industries. The purpose of the HCP is to provide a standardized, secure, and automated interface for slice lifecycle management across administrative boundaries. This solves the problem of operational complexity and enables new business models where verticals can self-serve, dynamically requesting and modifying slice resources based on their needs. It was motivated by the 5G vision of network-as-a-service and the need for technical enablers to support slice-as-a-service offerings. By defining the HCP, 3GPP facilitates interoperability between different vendors' management systems in the customer and provider domains, accelerating the adoption of network slicing for enterprise and industrial use cases.
Key Features
- Standardized logical interface for inter-domain management of network slices
- Defines a set of Management Service (MnS) producers and consumers
- Uses RESTful APIs with OpenAPI-based specifications
- Supports lifecycle operations for network slice instances (create, modify, monitor, terminate)
- Enables secure communication and authorization between customer and provider domains
- Works in tandem with the Vertical Coupling Plane (VCP) for end-to-end management
Evolution Across Releases
The Horizontal Coupling Plane was initially introduced in Release 15 as part of the 5G system architecture for management and orchestration. The initial definition established the concept, its role in the management architecture for network slicing, and the high-level requirements for interactions between the Communication Service Customer and Communication Service Provider management systems.
Defining Specifications
| Specification | Title |
|---|---|
| TS 38.124 | 3GPP TR 38.124 |