Call Flows
The following call flow depicts the integration of the IPAM in the SMF.

Step | Description |
---|---|
1 | IPAM populates the local cache and cache pod with the data configured under IPAM pool configuration. Split the address ranges according to the split size configured under address range. |
2 | The Node Manager (NM) receives UPF discovery or registration request. |
3 | The NM forwards the UPF registration request to IPAM for a given DNN or address type. |
4 | IPAM finds the pool for the given tag and address type and allocates a free address range against the given UPF key. |
5 | Register the UPF response, status, and route information. |
6 | The SMF service performs bring up of PDU session. The NM forwards the request to IPAM for the address allocation request. |
7 | IPAM receives the request for address allocation for tag, UPF key, Authority and Format Identifier (AFI), and Group Identifier (GrID). |
8 | IPAM allocates free address from the previously allocated address range and responds with the status and allocated address, and route information. |
9 | The SMF service performs bring down of PDU session. The NM forwards the request to IPAM for address release request. |
10 | IPAM receives the request for address release for pool name, UPF key, AFI, and GrID. |
11 |
IPAM adds the address to free list of the reserved address range and responds with the status and route information. |
12 |
IPAM receives UPF deregistration request with tag, UPF key, and AFI. |
13 |
Release all the address ranges from the pool associated to the tag, UPF key, and AFI. Then, move the address range to the free list. |
14 |
IPAM sends the UPF deregistration response along with the status and route information. |