NRF Architecture

NRF comprises of various microservices deployed in Kubernetes based Cloud Native Environment (CNE, example: OC-CNE) . Some common services like logs or metrics data collection, analysis and graphs or charts visualization, etc. is provided by the environment. The microservices integrates with them and provide them necessary data. The following diagram describes the overall architecture of the NRF:

Figure 1-1 Network Repository Function Architecture Diagram

The followings are the components of NRF product:

• NRF API Gateway
  All NRF service requests are sent to the NRF API Gateway. The API Gateway hides the deployment details of the NRF services and other components from other NFs in the CNE and external entities. It is deployed in the CNE as a Kuberbetes service by the NRF Helm Chart.

  Note:

  Ambassador is used as NRF API Gateway

  The primary functions of the NRF API Gateway are as follows:

  • The NRF endpoint hosts the FQDN(s) of the NRF deployment
  • Inspects the service URI and route the traffic to the appropriate upstream NRF micro-service
  • Measures the request count routed to each micro-service
  • Measures the response count based on the HTTP Status Code
  • Generates HTTP Trace data for the requests routed through
  • Generates the logs of the routing activity
  • Integrates with CNE common services EFK, Prometheus and Jaeger for sending them logs, metrics data and HTTP Tracing data respectively
• NF Registration MicroService

  This microservice handles the following service operations:

  • receives and handles NFRegister service requests from the NFs
  • receives and handles NFUpdate service requests from the NFs
  • receives and handles NFDeregister service requests from the NFs
  • stores the registered profiles in its own data store using the database service
  • receives and handles the Heart-beat messages from the NFs
  • monitors the heart-beat expiry, mark the NF profiles as suspended and act appropriately on the suspended NF profiles
• NF Subscription MicroService

  This microservice handles the following service operations:

  • receives and handles NFStatusSubscribe service requests from the NFs
  • receives and handles NFStatusUnsubscribe service requests from the NFs
  • receives and handles NFNotify service requests from the NFs
  • stores the subscription data in its own data store using the database service
• NF Discover MicroService

  This microservice handles the following service operations:

  • receives and handles NFDiscover service requests from the NFs
• NRF Auditor MicroService

  This microservice is internal to NRF. This microservice performs the following tasks:

  • finds and deletes the expired subscription records
  • finds and deletes the profile records which have been SUSPENDED for a very long time
  • processes the heartbeat records and update them if a heartbeat is missed
  • transitions the profiles from REGISTERED to SUSPENDED state if n consecutive heartbeats are missed

  For information on configuring these microservices, See the OCNRF Cloud Native Installation and Upgrade Guide.

• Data Service

  The data service is deployed by the CNE provider. It is a common CNE service with persistent data storage and highly available clustered MySql. The OCNRF microservices create their data store using the Data Service upon initialization.