Page 326 - 5G Basics - Core Network Aspects

1 Core network aspects

automatically. Thus, the network is required to initiate the FSC and move one or more IP flows by providing
a routing rule to the MUE updating the routing rules. Network initiated FSC is shown in Figure 7-3.

Figure 7-3 – Network initiated FSC

0. The MUE is connected to multiple access networks simultaneously and uses multiple connections
to send and receive IP flows.
1. The MPC-FE determines based on policy information and current MUE state that connection
modification should be initiated to move specific flows. The MPC-FE provides policy control rules
with access type information.
2. The MC-FE makes and assigns related rules for the access network to the MMF. The MMF installs
the rules.
3. The MMF sends the new routing rules to AC-FE(2).
4. The AC-FE(2) determines if the new routing rules or the modified routing rules need to be sent to
the MUE, based on the received policy control rules. The AC-FE sends the created or modified
routing rules to the MUE.
5. The MUE may accept or reject the routing rules. If the MUE rejects the routing rules, the MUE
provides a cause value indicating why the request was rejected. This cause value may be used by
the network to determine if the FSC operation can be requested again.
6. The MUE applies the accepted routing rules and acknowledges the applied rules in the ACK message
sent to the AC-FE(2).
7. The AC-FE(2) indicates to the MMF whether or not the routing rule can be enforced.
8. Resource release or modification procedures are executed for the resources associated with the
removed flows.

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