Map Rules for CPN-UPN Communication

The following tables explain the behavior of PFCP and GTP-u packets on UPN node when Flow sample and Forward list maps are configured with different combination of attributes.

Flow Sample Map Rules for CPN-UPN Communication

Rules and Notes:

■   For PFCP packets, RAN and Network Slice based flow sampling are not applicable as the PFCP packets do not contain any RAN or Network Slice parameters.
■   For GTP-u packets, if RAN and Network Slice enrichment are not performed, the packets will trigger a RAN PULL to get RAN information from the CPN. During this process (~3 seconds), GTP-u packets will be evaluated against any configured rules. If no match is found, they will either be dropped or sent to the collector. After this (~3 seconds), RAN or Network Slice flow sampling will apply if RAN enrichment is successful. If enrichment fails, GTP-u packets will again be evaluated against matching rules, dropped, or sent to the collector.
■   Below are the list of generic RAN, non RAN, and Network Slice parameters that can be configured for CPN-UPN communication:
o   Generic filter parameters - apn/imsi/imei/msisdn/version/interface
o   RAN filter parameters - eci/plmn-id/tac/tac-5g/nci
o   Network Slice parameters - nssid [SST or SST.SD] SD is optional

Generic Filter Parameters

 RAN Filter Parameters Network Slice Parameters

Flow sampling Status - PFCP Packets

Flow sampling Status - GTP-u packets

 

Yes

No

No
● PFCP packets matching the Generic Filter parameters configured are only flow sampled
● RAN flow sampling is not applicable
● GTP-u packets matching the Generic Filter parameters configured are only flow sampled
● RAN and Network Slice based flow sampling is not considered

No

Yes

No
● All PFCP packets are flow sampled
● RAN flow sampling is not applicable
● GTP-u packets matching the RAN Filter parameters configured are only flow sampled
● Network Slice based flow sampling is not considered

Yes

Yes

No
● PFCP packets matching the Generic Filter parameters configured are only flow sampled
● RAN flow sampling is not applicable
● GTP-u packets matching the RAN Filter and Generic Filter parameters configured are only flow sampled
● Network Slice based flow sampling is not considered

No

No

Yes
● All PFCP packets are flow sampled
● RAN and Network Slice flow sampling is not applicable
● GTP-u packets matching the Network Slice parameters are only flow sampled
● RAN based flow sampling is not considered

No

Yes

Yes
● All PFCP packets are flow sampled
● RAN and Network Slice flow sampling is not applicable
● GTP-u packets matching the RAN and Network Slice parameters are only flow sampled

Yes

No

Yes
● PFCP packets matching the Generic Filter parameters configured are only flow sampled
● RAN and Network Slice flow sampling is not applicable
● GTP-u packets matching the Generic Filter and Network Slice parameters are only flow sampled
● RAN based flow sampling is not considered

Yes

Yes

Yes
● PFCP packets matching the Generic Filter parameters configured are only flow sampled
● RAN and Network Slice flow sampling is not applicable
● GTP-u packets matching the Generic Filter, RAN and Network Slice parameters are only flow sampled

Note:  In UPN, when the flow sampling map contains both RAN related and generic rules, the session count in the map statistics increments when both types of rules are matched. This behaviour is expected, as the rule lookup occurs twice: before and after enrichment.
The initial rule lookup takes place when user tunnels are created from the PFCP packet, incrementing the session count for generic matching rules. After enrichment, a RAN update from the CPN triggers a second rule lookup to match RAN rules. For 5G sessions, the session count is based on the QFI per PDU session after enrichment.

Forward List Map Rules for CPN-UPN Communication

Rules and Notes:

■   For PFCP packets filtered for matching, RAN forward list is Not Applicable as the PFCP packets do not contain any RAN parameters.
■   For GTP-u packets filtered for matching, if RAN enrichment is not performed, the packets will trigger a RAN PULL to get RAN information from the CPN. During this process (~3 seconds), GTP-u packets will be evaluated against any configured rules. If no match is found, they will either be dropped or sent to the collector. After this (~3 seconds), RAN filtering will work if RAN enrichment is successful. If enrichment fails, GTP-u packets will again be evaluated against matching rules, dropped, or sent to the collector.
Database Contains Forward list Type Forward list Rule - APN

Forward list Rule - Interface

PFCP Packets Filtered for Matching

GTP-U Packets Filtered Matching

 

IMSI + RAN

IMSI

Yes

Yes

IMSI + APN + Interface

● PFCP packets matching IMSI, APN, and Interface are only forward listed
● RAN forward list is not applicable

IMSI + APN + Interface

● GTP-u packets matching IMSI, APN, and Interface are only forward listed
● RAN forward list is not considered

IMSI + RAN

IMSI

No

Yes

IMSI + Interface

● PFCP packets matching IMSI and Interface are only forward listed
● RAN forward list is not applicable

IMSI + Interface

● GTP-u packets matching IMSI and Interface are only forward listed
● RAN forward list is not considered

IMSI + RAN

IMSI

Yes

No

IMSI + APN

● PFCP packets matching IMSI and APN are only forward listed
● RAN forward list is not applicable

IMSI + APN

● GTP-u packets matching IMSI and APN are only forward listed
● RAN forward list is not considered

IMSI + RAN

IMSI

No

No

IMSI

● PFCP packets matching IMSI are forward listed
● RAN forward list is not applicable

IMSI

● GTP-u packets matching IMSI are only forward listed
● RAN forward list is not considered

IMSI + RAN

RAN

Yes

Yes

APN + Interface

● PFCP packets matching APN and Interface are only forward listed
● RAN forward list is not applicable

RAN + APN + Interface

● GTP-u packets matching the RAN, APN, and Interface are only forward listed

IMSI + RAN

RAN

No

Yes

Interface

● PFCP packets matching the Interface are only forward listed
● RAN forward list is not applicable

RAN + Interface

● GTP-u packets matching the RAN and Interface are only forward listed

IMSI + RAN

RAN

Yes

No

APN

● PFCP packets matching APN are only forward listed
● RAN forward list is not applicable

RAN + APN

● GTP-u packets matching RAN and APN are only forward listed

IMSI + RAN

RAN

No

No

All PASS

● All PFCP packets are forward listed
● RAN forward list is not applicable

RAN

● GTP-u packets matching the RAN are only forward listed

IMSI + RAN

ALL

Yes

Yes

IMSI + APN + Interface

● PFCP packets matching IMSI, APN, and Interface are only forward listed
● RAN forward list is not applicable

IMSI + RAN + APN + Interface

● GTP-u packets matching IMSI, RAN, APN, and Interface are only forward listed

IMSI + RAN

ALL

No

Yes

IMSI + Interface

● PFCP packets matching the IMSI and Interface are only forward listed
● RAN forward list is not applicable

IMSI + RAN + Interface

● GTP-u packets matching IMSI, RAN, and Interface are only forward listed

IMSI + RAN

ALL

Yes

No

IMSI + APN

● PFCP packets matching the IMSI and APN are only forward listed
● RAN forward list is not applicable

IMSI + RAN + APN

● GTP-u packets matching the IMSI, RAN, APN are only forward listed

IMSI + RAN

ALL

No

No

IMSI

● PFCP packets matching the IMSI are only forward listed
● RAN forward list is not applicable

IMSI + RAN

● GTP-u packets matching IMSI and RAN are only forward listed