Description
Product Specific Applications (PSA) is a term used across numerous 3GPP specifications to denote application functions or services that are not generic but are tied to a specific commercial product, service bundle, or use case. It is not a single protocol or network function but a conceptual entity used in requirement and architectural modeling. PSAs represent the logical endpoint or source of service-specific traffic and signaling that the 5G System (5GS) must support. They are often discussed in the context of service-based architecture, network exposure, and quality of service (QoS) differentiation.
Architecturally, a PSA interacts with the 5G Core Network (5GC) through defined interfaces, primarily the Network Exposure Function (NEF) or directly with the User Plane Function (UPF) for traffic steering. The PSA can be an Application Function (AF) as defined in the 5GC architecture, but with the distinguishing characteristic of being product-specific. This means its communication with the network carries requirements unique to the product it enables, such as specific QoS parameters (e.g., latency, reliability), charging policies, or mobility restrictions. The 5GC uses the information provided by or about the PSA to apply appropriate network policies.
How it works involves the PSA (or an entity representing it, like an AF) providing session or service-related information to the 5GC. For example, a PSA for a real-time gaming service might request a guaranteed bit rate and low-latency QoS flow for its users via the NEF. The Policy Control Function (PCF) would then generate policies based on this request and the user's subscription, and the Session Management Function (SMF) would enforce them by configuring the UPF accordingly. The role of the PSA concept is to provide a formal model for these product-specific interactions, ensuring the network can be dynamically tailored to support a vast array of specialized services beyond basic connectivity, which is central to the 5G vision of network-as-a-service.
Purpose & Motivation
The concept of Product Specific Applications exists to address the need for the 3GPP system to support a diverse and ever-growing ecosystem of specialized services, each with unique network requirements. In early mobile networks, services were largely monolithic (e.g., voice, SMS, basic internet). As networks evolved, operators and third parties began offering differentiated products like streaming bundles, IoT solutions, and enterprise VPNs, which required the network to treat their traffic differently.
PSA provides a standardized way to model these bespoke services within the 3GPP architecture. It solves the problem of how to formally describe and integrate the requirements of a specific commercial product into the network's control and management planes. Before such modeling, enabling a new service often required proprietary integrations or broad, inefficient network configurations. The PSA concept, particularly as refined in the 5G service-based architecture, allows for dynamic, policy-driven network slicing and QoS management on a per-application or per-product basis. This enables operators to efficiently monetize their networks by offering tailored connectivity as a product feature.
Detected Changes Across Releases
from 3GPP Change RequestsSpecific changes extracted from the „Change history“ tables of 3GPP specifications (91 CRs across 5 releases). Complements the general historical overview above with the evidence-based evolution of this function.
Studied in Rel-8, normative work from Rel-15.
In Release 15, the PSA function was newly introduced as the "Product Specific Applications" function, which is referenced within the architecture for enabling Edge Applications. The specification defines its role in the context of providing specific network capabilities and characteristics for logical networks, aligning with the broader framework for data connectivity and services in the 5G System.
- Clarification on UE specific DRX parameter from old AMF to new AMF TS 23.501CR0014
- UE-specific DRX parameter negotiation between UE and AMF TS 23.501CR0031
- UE specific DRX parameters for CM-CONNECTED with Inactive state TS 23.501CR0177
- Miscellaneous Corrections to SM specifications (SSC mode, PCFP reference, etc.) TS 23.501CR0547
- Obsolete reference to Lawful Interception specifications TS 23.501CR0551
- UE requests specific QoS handling for selected SDF TS 29.512CR0026
+ 4 more changes
In Release 16, key enhancements for product-specific applications included the introduction of Network Slice-Specific Authentication and Authorization, which introduced the concept of a Pending NSSAI during registration procedures. Furthermore, support was added for applications with specific QoS hints, enabling more granular traffic detection and forwarding treatment based on an Application Identifier. The release also provided clarifications and alignments for handling vendor-specific information elements.
- NEF service for service specific parameter provisioning TS 23.501CR0878
- Sol#6 specific updates to 5.6.4.2 TS 23.501CR0897
- Introduction of Slice-Specific Authentication and Authorisation TS 23.501CR1174
- Alignment of IMS Voice Service via EPS Fallback with RAN specifications TS 23.501CR1333
- Introduction of UE specific DRX for NB-IOT TS 23.501CR1849
- Support of applications with specific QoS hints TS 29.513CR0151
+ 18 more changes
In Release 17, key enhancements for the PSA (PDU Session Anchor) function included the introduction of an AF request for simultaneous connectivity over source and target PSA during edge relocation, enabling smoother service continuity. The release also specified support for outer header removal at the PSA UPF and clarified procedures for the allocation of access-specific UDP ports or MAC addresses. Furthermore, it added service-specific authorization within the service parameter provisioning procedure and defined mechanisms for subscription to the detection of traffic for one or more applications.
- EC KI2 Target PSA buffering TS 23.501CR2646
- Void I-SMF/V-SMF Restoration procedure from normal specification clause TS 23.527CR0036
- Clarification on Allocation of Access Specific UDP Ports or MAC Addresses TS 29.244CR0600
- Outer Header Removal for PSA UPF TS 29.244CR0644
- AF Request for Simultaneous Connectivity over Source and Target PSA at Edge Relocation TS 29.512CR0872
- Notification on the outcome of UE Policies delivery due to service specific parameter provisioning TS 29.513CR0295
+ 20 more changes
In Release 18, the PSA (PDU Session Anchor) UPF function was enhanced with new selection descriptions and received clarifications for N19 packet forwarding during local switching scenarios. Support was added for VPLMN-specific offloading policies and URSP rules, enabling more granular, visiting network-controlled traffic steering. Furthermore, the release introduced an EAS-specific UE identifier (Edge UE ID) to better support edge application sessions.
- Add description for PSA UPF selection TS 23.501CR3985
- Clarification of N19 forwarding for local switch via PSA UPF on GEO TS 23.501CR3999
- EAS-specific UE ID (Edge UE ID) TS 23.558CR0229
- Enabling ACR with cloud applications TS 23.558CR0264
- Support of VPLMN Specific Offloading Policy for HR-SBO TS 29.512CR1068
- Support of VPLMN Specific Offloading Policy for HR-SBO TS 29.513CR0456
+ 8 more changes
In Release 19, enhancements for the PSA function included improved UPF selection and re-selection mechanisms specifically for Local-PSA (L-PSA) scenarios, considering N6 delay requirements. The release also introduced clarifications and alignments for handling AF-specific UE identifiers and refined protocol-specific configuration parameters for N6 delay measurements. Furthermore, updates were made to the handling of link-specific and MPQUIC proxy IP addresses within IPv4v6 PDU sessions.
- Support of L-PSA UPF Selection Considering N6 Delay TS 23.501CR5437
- Header Handling parameters alignment with 29.514 specification TS 29.244CR0937
- Security related protocol-specific configuration parameters for N6 delay measurement TS 29.244CR0975
- Handling of AF Specific UE IDs TS 23.501CR6168
- Clarification to UPF selection based on specific UPF functionalities TS 23.501CR6056
- Alignment on L-PSA UPF re-selection and/or an edge relocation TS 23.501CR6060
+ 11 more changes
Explore further
Broader topics and technologies where PSA plays a role.
Defining Specifications
3GPP specifications that define or reference PSA, with the latest known release. Sourced from the 3GPP document catalog — see methodology.
| Specification | Title | Release |
|---|---|---|
| TS 23.501 vk00 | 5G System Architecture Stage 2 | Rel-20 |
| TS 23.527 vj50 | 5G System Restoration Procedures | Rel-19 |
| TS 23.558 vk00 | Architecture for Edge Applications | Rel-20 |
| TS 23.700 vk00 | XR Services Application Enablement Layer | Rel-20 |
| TR 23.794 vh00 | Study on enhanced IMS to 5GC integration | Rel-17 |
| TR 26.803 vh00 | 5G Media Streaming Extensions for Edge Processing | Rel-17 |
| TS 26.804 vj10 | 5G Media Streaming Extensions Study | Rel-19 |
| TR 26.806 vi00 | Technical Report on Smartly Tethering AR Glasses | Rel-18 |
| TR 28.822 vh00 | Charging for 5G LAN Services Study | Rel-17 |
| TR 28.833 vi01 | Technical Report on 5G LAN-type Service Management | Rel-18 |
| TS 29.244 vj40 | PFCP Specification for Control/User Plane Separation | Rel-19 |
| TS 29.512 vj40 | 5G Session Management Policy Control Service | Rel-19 |
| TS 29.513 vj40 | 5G PCC Signalling Flows & QoS Mapping | Rel-19 |
| TS 29.514 vj40 | 5G System; Policy Authorization Service; Stage 3 | Rel-19 |
| TS 29.519 vj40 | UDR Usage for Policy & Exposure Data | Rel-19 |
| TS 29.892 vg00 | Study on User Plane Protocol in 5GC | Rel-16 |
| TS 32.102 vj00 | Telecom Management Physical Architecture Framework | Rel-19 |
| TS 32.150 vj00 | IRP Concept and Definitions | Rel-19 |
| TR 33.739 vi10 | Study on security enhancement of support for | Rel-18 |