Description
The Vertical Application Layer (VAL) is a comprehensive service architecture specified by 3GPP, primarily in TS 23.434 and related specs. It is designed as an intermediary layer that sits between vertical industry applications (the clients) and the 3GPP network exposure functions (like NEF) or data network services. The VAL provides a vertical-specific abstraction of the underlying 5G network capabilities, data management, and device management services. Its architecture typically involves a VAL Server, VAL Clients (within vertical devices/sensors), and a VAL Management System.
The core functionality of VAL is to manage Vertical Application Layer Services (VAL Services). A VAL Service is a logical entity that represents a set of capabilities offered to a vertical application, such as group management for devices, data reporting and subscription, command delivery, or location tracking. The VAL defines standardized data models (e.g., for sensors, actuators, robots) and communication procedures using RESTful APIs, often leveraging HTTP/2 or MQTT. Key components include the VAL Service Management Function, which handles the lifecycle (creation, update, deletion) of VAL Services; the VAL Configuration Management, which provisions parameters to VAL Clients; and the VAL Data Management, which handles the storage, aggregation, and exposure of data collected from vertical devices.
How it works: A vertical application, such as a factory control system, interacts with the VAL Server via its APIs to create a VAL Service, for instance, a 'Robot Fleet Management Service'. The VAL Server then configures the relevant VAL Clients (software on the robots) with the service parameters. The robots (VAL Clients) use the VAL protocols to register, report telemetry data (like position, status), and receive commands from the application through the VAL Server. The VAL layer handles the translation between the application's intent and the necessary network actions. Crucially, it can interact with the 5G Core's Network Exposure Function (NEF) to request network capabilities like QoS guarantees for a specific robot group or the activation of a network slice tailored for the factory. This allows the vertical application to be largely agnostic to the specific 3GPP network implementation details while still leveraging advanced 5G features.
Purpose & Motivation
VAL was created to address the key challenge of integrating diverse and specialized vertical industry applications with the generic 5G system. Previous cellular generations were primarily designed for human-centric communication (voice, internet). 5G's promise to serve verticals like Industry 4.0, smart grids, and healthcare introduced a new set of requirements: ultra-reliable low-latency communication (URLLC), massive machine-type communication (mMTC), and precise network resource control. Without a standardized application layer, each vertical would need to develop custom, proprietary integrations with the 5G core, leading to complexity, high costs, and lack of interoperability.
The motivation for VAL in Rel-16 was to provide a common, 3GPP-standardized 'on-ramp' for verticals into the 5G network. It solves the problem of fragmentation by offering a uniform set of APIs and data models for verticals, shielding them from the underlying network complexity. This enables vertical application providers to develop once and deploy across different mobile network operators and countries. VAL also empowers network operators to expose and manage advanced 5G features (e.g., network slicing, edge computing, QoS) to vertical customers in a controlled, automated, and billable manner through a well-defined service layer. It is a critical enabler for the 5G business-to-business (B2B) and business-to-business-to-consumer (B2B2C) ecosystem, turning network capabilities into consumable services for industries.
Classification
Release Timeline
Detected Changes Across Releases
from 3GPP Change RequestsSpecific changes extracted from the „Change history“ tables of 3GPP specifications (52 CRs across 5 releases). Complements the general historical overview above with the evidence-based evolution of this function.
In Release 16, the VAL function introduced specific procedures for location reporting, including corrections to location notifications to the VAL server and updates to client-triggered or VAL server-triggered location reporting. These enhancements were part of integrating VAL server procedures, such as on-demand location monitoring from a SEAL LMS, for vertical applications like UAS. The release also defined applicable procedures for network resource management and network slice capability exposure services, where the VAL server interacts with SEAL servers over the SEAL-S reference point.
In Release 17, the VAL function introduced new capabilities for network slice adaptation and optimization based on VAL server policy for vertical applications. It enhanced procedures for VAL UE information in configuration management and added support for temporary group formation within a VAL system. Furthermore, the release specified the use of CoAP for location reporting procedures and clarified identities and information flows, such as distinguishing between UE ID and CAA level UAV ID for UAS applications.
- Network slice adaptation for VAL applications TS 23.434CR0032
- Enhancement of information flows to add VAL service specific information TS 23.434CR0044
- add VAL UE Information to configuration management procedure TS 23.434CR0060
- Addition of CoAP for Client-triggered or VAL server-triggered location reporting procedure TS 24.545CR0046
- Add VAL service specific information TS 29.549CR0063
- Supporting temporary group formation within a VAL system TS 29.549CR0066
+ 2 more changes
In Release 18, the VAL function introduced new capabilities for VAL server provisioning to the Identity and Key Management Servers and enhanced location-based services with VAL service area identifiers integrated into the SS_LocationReporting and SS_LocationMonitoring APIs. It also expanded inter-system support for VAL service switching between 5G and LTE/EPS and defined new procedures for VAL server policy provisioning, update, and usage reporting. Furthermore, support was added for the VAL server to act as a Multicast/Broadcast Service Application Function (MBS AF) and for VAL application performance analytics APIs.
- VAL Server provisioning TS 23.434CR0106
- VAL service area identifier usage TS 23.434CR0136
- VAL service inter-system switching between 5G and LTE TS 23.434CR0140
- VAL service over 5GS supporting EPS interworking TS 23.434CR0141
- Information flow for VAL server provisioning to the Identity Management Server TS 23.434CR0159
- VAL server provisioning for Key Management Server TS 23.434CR0160
+ 20 more changes
In Release 19, key enhancements for the VAL function included the introduction of SEALDD-enabled congestion control supporting the L4S mechanism for both HTTP and CoAP protocols, along with new support for VAL performance analytics specifically for tethered UEs. The release also added APIs for a VAL server to obtain the SCAI and introduced monitoring capabilities for SEALDD client connection status and congestion. Furthermore, procedures such as the event-triggered and client/VAL server-triggered location reporting for CoAP were corrected and aligned.
- Correction on SEALDD enabled congestion control for VAL application by supporting L4S mechanism TS 23.433CR0021
- Add the APIs for VAL server obtaining the SCAI TS 23.434CR0369
- Support for VAL performance analytics for tethered UEs TS 23.436CR0044
- Updates for SEALDD enabled congestion control for VAL application by supporting L4S mechanism for HTTP TS 24.543CR0027
- Updates for SEALDD enabled congestion control for VAL application by supporting L4S mechanism for CoAP TS 24.543CR0028
- Support SEALDD client connection status monitoring for VAL applications TS 29.548CR0015
+ 6 more changes
In Release 20, the VAL function introduced new capabilities for Federated Learning (FL) integration, specifically enabling the registration and discovery of VAL clients as AI/ML members and allowing VAL servers to register as FL members. It also enhanced SEALDD-enabled congestion control for VAL applications and introduced sample alignment enablement for VAL servers within the VFL (Vertical Federated Learning) framework. These additions expanded the VAL architecture's role in supporting distributed AI workloads and managing associated network resources.
Explore further
Broader topics and technologies where VAL plays a role.
Defining Specifications
3GPP specifications that define or reference VAL, with the latest known release. Sourced from the 3GPP document catalog — see methodology.
| Specification | Title | Release |
|---|---|---|
| TS 23.255 vj50 | UAS Application Layer Support | Rel-19 |
| TS 23.433 vk00 | SEAL Data Delivery (SEALDD) for Verticals | Rel-20 |
| TS 23.434 vk00 | Service Enabler Architecture for Verticals | Rel-20 |
| TS 23.435 vj30 | Network Slice Capability Exposure Procedures | Rel-19 |
| TS 23.436 vk00 | ADAEnabler Functional Architecture and Information Flows | Rel-20 |
| TS 23.438 vk10 | SEAL Digital Asset Service for Metaverse | Rel-20 |
| TS 23.482 vk00 | AIML Enablement Service Architecture | Rel-20 |
| TS 23.554 vj70 | MSGin5G Service Application Architecture | Rel-19 |
| TS 23.700 vk00 | XR Services Application Enablement Layer | Rel-20 |
| TR 23.745 vh00 | Study on App Layer Support for Factories of the Future in 5G | Rel-17 |
| TS 24.542 vj00 | SEAL Notification Management Protocol | Rel-19 |
| TS 24.543 vj50 | SEAL Data Delivery Management Protocol | Rel-19 |
| TS 24.545 vj40 | SEAL Location Management Protocol Specification | Rel-19 |
| TS 24.547 vj00 | SEAL Identity Management Protocol | Rel-19 |
| TS 24.548 vj10 | SEAL Network Resource Management Protocol | Rel-19 |
| TS 24.549 vj10 | SEAL Network Slice Capability Enablement Protocol | Rel-19 |
| TS 24.550 vj00 | Metaverse Enablement Services Protocol | Rel-19 |
| TS 24.559 vj41 | Application Data Analytics Enablement Services | Rel-19 |
| TS 24.560 vj00 | AIML Enablement (AIMLE) Services Stage 3 Protocol | Rel-19 |
| TR 26.857 vi00 | Technical Report on Media Service Enablers | Rel-18 |
| TS 29.482 vj00 | SEAL AIMLE Services Stage 3 Protocol | Rel-19 |
| TS 29.548 vj40 | SEAL Data Delivery Server Services Stage 3 | Rel-19 |
| TS 29.549 vj40 | SEAL API Specification for Vertical Applications | Rel-19 |
| TS 29.561 vj30 | 5G Interworking with External Data Networks | Rel-19 |
| TS 33.434 vj00 | Security aspects of SEAL for verticals | Rel-19 |
| TR 38.857 vh00 | Study on NR Positioning Enhancements | Rel-17 |
