Dual Stack Support on S1-U and N3 Interfaces

UPF supports dual stack to handle IPv4 and IPv6 connections on N3 and S1-U interfaces.

Default Setting: Enabled – Always-on

Redirect URL Encryption

UPF supports encryption of dynamic fields in the redirected URL using the Blowfish and AES encryption methods.

Default Setting: Disabled – Configuration required to enable

Behavior of Sx Peers in SxDemux

Previous Behavior: When the Sx peer moved from Associated state to New state, the Sx peers to be checkpointed for SxDemux recovery were deleted from SxDemux.

New Behavior: When the Sx peer moves to Released state, the Sx peers to be checkpointed for SxDemux recovery will be deleted from SxDemux.

Extended Intercept ID Display in CLI Output

Previous Behavior: The output of the show lawful-intercept all CLI command displayed only the Intercept ID with the "Intercept-ID" variable.

New Behavior: The "Intercept-ID" variable in the output show lawful-intercept all CLI command will also display the Extended Intercept ID (XID) if received through SMF.

Handling Sx Services after Unplanned Switchover

Previous Behavior: On Sx-service deletion, SxDemux sends DeRegistration information to VPNMgr to release IP pools related to peers under that service.

New Behavior: On Sx-service deletion, SxDemux will first check other Sx services. If another Sx service exists with the same PFCP peer, then SxDemux will not send DeRegistration request to the VPNMgr.

HTTP Request Methods during Redirection

Previous Behavior: HTTP redirection was applied only on HTTP GET and not applied on other request methods such as HTTP POST.

New Behavior: HTTP redirection will now be applied on all HTTP Request methods.

Increase in QER Limit per PDR

The QER limit per PDR is increased for the PTT (Push to Talk) feature.

Previous Behavior: UPF supported a maximum number of two QERs per PDR association.

New Behavior: The maximum number of QERs per PDR limit is increased to three in this release.

Length Validation of OHC Description Field

Previous Behavior: When the OHC (Outer Header Creation) description field was set to 768, length validation was not done.

New Behavior: When the OHC IE receives the Outer Header Creation description field with both GTP-U/UDP/IPv4 and GTP-U/UDP/IPv6, the length of the OHC IE as 26 bytes is validated. If the length is not 26 bytes, then Sx message responds with the PFCP_CAUSE_MANDATORY_IE_INCORRECT cause code with Offending IE OUTER_HDR_CREATION.

Maximum PDR Limit

Previous Behavior: UPF did not enforce a maximum limit for installed PDRs per subscriber.

New Behavior: UPF now enforces a maximum limit of 356 installed PDRs per subscriber.

If the number of installed PDRs exceeds the maximum limit due to new Create PDRs in Modify Request, then Sx/N4 Modify Request is rejected.

Message Handling during Inter-PLMN Handover

Previous Behavior: When inter-PLMN handover was detected, UPF did not validate Create PDR for rulebase in Sx Modify Request.

New Behavior: When inter-PLMN handover is detected, validation is enforced on UPF to reject Sx Modify Request without any Create PDR for the rulebase.

OHC IE Validation on N4 Interface

Previous Behavior: For N4 calls, the OHC (Outer Header Creation) IE in an uplink FAR led to validation failure and rejection of Sx Establishment/Modification Request.

New Behavior: If an OHC IE is present in an uplink FAR for N4 calls, UPF establishes Sx Establishment/Modification Request without failure.

Customer Impact: This behavior might impact the OHR and OHC functionality.

Port Number Behavior in EDR Module Configuration

After Cisco SSH or SSL upgrade, the port number behavior has changed for the EDR-module configuration.

Previous Behavior: In the EDR-module configuration, the default SFTP port number "0" was selected automatically and connected to port 0 when colon was specified.

For example:

cdr transfer-mode push primary url sftp://root:starent@192.0.2.1:/root/EDR/ via local-context

New Behavior: The EDR-module configuration is updated to allow the new default SFTP port number "22" or disallow the port number without specifying a colon.

For example:

cdr transfer-mode push primary url sftp://root:starent@192.0.2.1:22/root/EDR/ via local-context (with default SFTP port number)

cdr transfer-mode push primary url sftp://root:starent@192.0.2.1/root/EDR/ via local-context (without colon)

User Plane Advertisement through Created PDR IE or Traffic Endpoint IE

Previous Behavior: The Local F-TEID in Create PDR or Create Traffic Endpoint IE was populated with the local GTP-U endpoint. This endpoint is allocated based on the configuration irrespective of Outer Header Removal received in the Create PDR IE. For example, if the GTP-U service configuration supported both IPv4 and IPv6 addresses, then both addresses are allocated and advertised in the Create PDR and Create Traffic Endpoint IEs.

New Behavior: The Local F-TEID allocation process works as earlier. With this release, the User Plane advertises the allocated F-TEID to the Control Plane through Create PDR or Create Traffic Endpoint IE in the following scenarios:

• Outer Header Removal that is received in the Create PDR IE is also considered while populating Create PDR or Create Traffic Endpoint IE.

• If Outer Header Removal is received as GTP-U, UDP, or IP, then the local GTP-U endpoint is advertised as allocated. This implies that if both IPv4 and IPv6 addresses are configured in the GTP-U service, then both addresses are allocated and advertised. If either IPv4 or IPv6 address is configured, then only the required address is allocated and advertised through Create PDR or Create Traffic Endpoint IE.

• If Outer Header Removal is received as GTP-U, UDP, or IPv4, then only the IPv4 address is advertised even if both addresses are configured.

• If Outer Header Removal is received as GTP-U, UDP, or IPv6, then only the IPv6 address is advertised even if both addresses are configured.

Customer Impact: The behaviour of Local F-TEID in Create PDR or Create Traffic Endpoint IE is changed.