PCF Architecture

The PCF architecture is built on a multi-layer platform, which enables efficient policy control and management in the 5G Core network.

PCF Architecture

At a high level, the components in the architecture perform the following:

  1. External Endpoint

    • REST-EP— It is a RESTful interface, which provides a channel for the 5G inbound and outbound messages.

    • LDAP-EP, UAPI, and CRD API— Provides interfaces for PCF communications.

    • Diameter-EP—Responsible for routing the Diameter traffic.

  2. Processing Layer

    • grPC—Provides a framework that enables the internal processes to communicate with each other and synchronize their events.

    • PCF-Engine—Hosts the business logic of PCF and responsible for driving the rules engine for making crucial policy decisions.

  3. Configurations

    • Policy Builder—Allows configuration of the PCF cluster of virtual machines (VMs) and configuration of services and advanced policy rules.

    • PCF Central—Provides a unified GUI that allows you to configure Policy Builder, manage custom reference table data, and initiate the Web-based applications and utilities.

    • Ops Center—Allows you to configure and manage the applications and pods configuration.

  4. Storage Layer

    • Binding Database Client—Provisions the client to look up the PCRF Mongo Binding Database for information about the secondary key lookup across 4G and 5G.

    • MongoDB—Preserves the subscriber-specific, balance data, and admin configuration data.

    • Session store—Contains the data which CDL accesses for processing a session persistence activity. Stores the PCF sessions.

    • Etcd—Contains the Diameter endpoint configurations.