Identification with Peer Node Call Flow

This section describes Identification with Peer Node call flow.

Identification with Peer Node Call Flow
Identification with Peer Node Call Flow Description

Step

Description

1

If the peer node is an AMF, then new AMF sends a transfer request to the old AMF, with type set to “INITIAL REGISTRATION”, including the whole registration request received by it.

2

The old AMF checks the integrity protection of the request, and if integrity checks pass, responds with the UE context, but without any SMF information.

3

The old AMF checks the integrity of the message that is received from the new AMF. If the integrity check passes, the old AMF packages the attributes of the UE that is available in the response to the transfer request. If the request was for mobility updating, PDU session information present in the old AMF is sent to the new AMF.

4

AMF releases any resources that the UE held at any SMF.

5

SMF responds to the AMF request.

6

The new AMF sends a transfer update message to the old AMF.

7

The old AMF responds with a “204 OK” indicating that the transfer is successful.

8

If the old node is an MME, then AMF sends an identity request message to MME along with the registration request received.

9

MME checks the integrity of the message it receives. If integrity checks pass, the MME returns the MM context.

At the end of a successful transfer from a peer node, AMF issues a security mode command with a mapped security context (from LTE) or a non-current security context (5G) towards the UE.