Progressive discovery for routing to a group of network functions

A network function repository function, NRF, entity comprising:

• processing circuitry;
• and
• memory coupled with the processing circuitry,
• wherein the memory includes instructions that when executed by the processing circuitry causes the NRF to perform operations comprising to:
• receive a network function, NF, discovery request from an access and mobility management function, AMF, entity, the NF discovery request having a communication device identifier and a NF type identifier;
• match the communication device identifier with one of a plurality of communication device identifier ranges configured by the NRF entity;
• extract a group identifier, groupId, configured for the one of the pluralities of communication device identifier ranges;
• build a list of registered NF profiles matching the NF type identifier and registered with the groupId;
• transmit the list of registered NF profiles including the groupId and a NRF mapping indication to the AMF entity;
• receive a groupId subscribe request from the AMF entity,
• the groupId subscribe request requesting that notifications be sent only from removed communication device ranges;
• add a communication device range to the groupId without providing a notification to the AMF entity;
• and
• responsive to removing a communication device range to the groupId,
• provide a notification to the AMF entity that includes the groupId, and
• an identification of the communication device range removed.

A method performed by an access and mobility management function, AMF, entity, the method comprising:

• responsive to receiving an initial registration request from a communication device, transmitting a network function, NF, discovery request to a network function repository function, NRF, entity, the NF discovery request comprising a communication device identifier and a NF type identifier;
• receiving a list of registered NF profiles including the groupId and
• a NRF mapping indication indicating that the mapping of communication device identifier ranges to the groupId is performed by the NRF entity;
• transmitting a groupId subscribe request to the NRF entity,
• the groupId subscribe request requesting that notifications be sent only from removed communication device ranges;
• receiving a notification from the NRF entity that includes the groupId, and
• an identification of the communication device range removed;
• and
• removing the communication device range from the groupId in cache memory.