cnSGW-C supports interaction of eMPS with GTPv2 load or overload feature. It supports excluding eARPs /APNs/Emergency call during self-protection mode in GTPv2 load or overload feature.

cnSGW-C can exclude the dnn-list, arp-list, and qci-list from the rejection for incoming request messages in self-protection mode. cnSGW-C excludes this rejection in the following manner:

• Excludes the dnn-list from rejection for any call level procedure when subscriber APN name (NI+OI) matches with overload-exclude-profile

• Excludes bearer modification or creation from rejection for any new or existing ARP (Priority-Level) value

• Excludes bearer modification or creation from rejection for any new or existing QCI value.

• Excludes the delete bearer or the session operations, such as Delete Bearer Request, Delete Session Request, Delete Bearer command from rejection irrespective of the overload-exclude-profile configuration

Note	cnSGW-C does not support message throttling.

Priorities determine the order in which service requests are dequeued by a server. For example, the priority that client assigns to individual services can range from 0 to 15, where 0 represents the highest priority.

In cnSGW, the cnSGW service sends the Inter-process Communication (IPC) message to the protocol pod for Wireleass Priority Service (WPS) session using Priority IPC Stream.

cnSGW creates the message-priority profile to define priorities either at global level or at each interface level (PFCP, GTP). You can select the Message Priority value based on:

• ARP and QCI received in Bearer context in the Create Session Request (CSR), Create Bearer Response (CBR), and Create Session Response.

• Update Message priority value based on ARP and QCI received in Bearer context in the Update Bearer Request (UBR).

cnSGW supports the following functionalities:

• WPS sessions per Roaming partner.

• Exclusion of WPS sessions from overload throttling.

• Session type conflict resolution at cnSGW.

• WPS sessions handing at UPF over Sxa Interface for collocated subscriber.

• WPS session monitoring.

Operators can monitor the S-GW service statistics for WPS users and users can also monitor number of active WPS sessions.

The Message Priority (MP) mechanism functions are:

• MP (gtp, pfcp) is copied to transactions created for handling an incoming message and the same is copied to child transactions. These priority values are also copied into IPC metadata to send it across to destination pods.

• Protocol pods (protocol, gtp) detect the incoming messages as WPS messages based on the message priority available in the incoming message. These message protocol pods use priority IPC streams toward a service pod.

Message Priority Profile Selection Logic

The following conditions apply for Message Priority Profiles selection:

• Subscriber-policy must define group of subscriber and associated Operator policy.

• Operator policy must define the associated DNN policy.

• DNN policy must define a list of DNN and the associated DNN profile.

• DNN profile must have an associated QoS profile name and WPS Profile name.

• QoS Profile must have an associated message-priority-profile.

• If the message-priority-profile is configured in WPS Profile and in S-GW QoS Profile for DNN, then the message-priority-profile configured in WPS profile takes priority.

• If any message priority configuration is changed at run time, it is applicable for the new calls. For existing calls, new configuration is applicable when the Bearer is updated or a new Bearer is added.

• The existing Message Priority gets displayed in outbound messages that are selftriggered, for example, DDN.

• If an incoming PDN level GTP message such as CSReq, MBReq, DSReq, CBReq, DBReq, UBReq is received with valid message priority and if copy-incoming is set to true for any of the Bearers in that PDN, then the received messages priority gets copied in all the outgoing GTP/PFCP messages that are triggered by that incoming message.

• If an incoming UE level GTP message such as HO DSReq, RAB is received with valid message priority and copy-incoming is set to true for any of the bearers in the PDN, then the received message priority will be copied in all outgoing GTP/PFCP messages(for that PDN) triggered by that incoming message.

• If an incoming PFCP message such as Session report is received with valid messages priority and copy-incoming is set to true for any of the Sx bearer in that Sx session, then received messages priority gets copied in outgoing response messages.

• Messages priority value is displayed in outgoing messages based on the following logic:

  • For GTP Messages:

    • For PDN level messages: If a PDN have multiple bearers which are marked as WPS (having different GTP message priorities), in that case highest messages priority (0 is highest and 15 is lowest) will be copied into outgoing GTP messages.

    • For UE level GTP messages: If UE have multiple bearers which are marked as WPS (having different GTP message priorities), in that case the highest messages priority(0 is highest and 15 is lowest) will be copied into outgoing GTP messages.

  • For PFCP Messages, if a Sx session has multiple bearers, which are marked as WPS (having different PFCP message priorities), in that case the highest messages priority (0 is highest and 15 is lowest) gets copied into outgoing PFCP messages.

The following is an example configuration.

config
   profile wps wp1
     arp 2 message-priority-profile message_priority_name
   end

To verify the configuration:

show full-configuration profile wps wps1
profile wps wps1
arp 2 message-priority-profile mp1
exit

The following is an example configuration.

config
   profile sgw sgw1
     wps-profile wp1
     end

To verify the configuration:

show running-config profile sgw
profile sgw sgw1
wps-profile wp1

The following is an example configuration.

 config
   profile dnn dnn1
   wps-profile wps1
   end

To verify the configuration:

show running-config profile dnn 
profile dnn dnn1
wps-profile wps1

To configure the Overload Exclude profile, use the following configuration:

config 
   profile overload-exclude overload_exclude_profile_name 
      dnn-list list_of_dnn  
      arp-list list_of_arp 
      qci-list list_of_qci 
      end 

NOTES:

• overload-exclude overload_exclude_profile_name — Specify the exclude overload profile name.

• dnn-list list_of_dnn —Specify the list of DNNs that needs to be excluded from throttling decision. Maximum three entries are allowed.

• arp-list list_of_arp —Specify the ARP list that needs to be excluded from throttling decisions. Must be an integer in the range of 1-15. Maximum eight entries are allowed.

• qci-list list_of_qci —Specify the QoS Class Identifier to be excluded from throttling decisions. Must be an integer in the range of 1-.254. Maximum 8 entries are allowed. For example, range values can be 1-9,65,66,69,70,80,82,83,128-254.

The association of the Overload-Profile and the SGW-Profile, can be configured.

To configure this feature use the following configuration:

config 
    profile overload overload_profile_name 
        overload-exclude-profile self-protection self_protection_profile_name 
    node-level 
        tolerance 
            minimum min_percentage 
            maximum max_percentage 
        reduction-metric 
            minimum min_percentage 
            maximum max_percentage 
            advertise 
            interval interval_value 
            change-factor 
            exit 
        interface gtpc 
            overloaded-action [ advertise ] 
            exit 
        exit 
    exit 
    profile load load_name 
    load-calc-frequency load_calc_frequency_value 
    load-fetch-frequency load_fetch_frequency_value 
    advertise 
    interval interval_value 
    change-factor change_factor_value 
    profile overload-exclude overload_excude_profile_name   
        arp-list list_name_arp 
        dnn-list list_name_dnn 
        message-priority message_priority 
        procedure-list message_priority 
        qci-list list_name_qci 
        qi5-list list_name_qi5 
    exit 
    interface gtpc 
    action advertise 
    exit 
exit 
profile sgw sgw_name 
load-profile profile_name 
overload-profile overload_profile_name 
end 

NOTES:

• overload overload_name —Specify the overload protection profile name. Must be a string.

• overload-exclude-profile —Excludes profiles for overload scenarios.

• self-protection overload_value —Specify the profile to be excluded for self-protection. Must be a string.

• tolerance minimum min_percentage —Specify the minimum tolerance level below which the system is in a normal state. Must be an integer in the range of 1-100. The default value is 80.

• tolerance maximum max_percentage —Specify the maximum tolerance level above which the system is in a self-protection state. Must be an integer in the range of 1-100. The default value is 95.

• reduction-metric minimum min_percentage —Specify the percentage of reduction along with minimum tolerance-level for configuration. Must be an integer in the range of 1-100. The default value is 10.

• reduction-metric maximum max_percentage —Specify the percentage of reduction along with maximum tolerance-level for configuration. Must be an integer in the range of 1-100. The default value is 100.

• interval interval_value —Specify the advertising interval in seconds. Must be an integer in the range of 0-3600. The default value is 300 seconds.

• validity validity_value —Specify the validity period of the advertised OCI value in seconds. Must be an integer in the range of 1-3600. The default value is 600 seconds.

• change-factor change_factor_value —Specify the minimum change between current OCI and last indicated OCI, after which the advertising should happen. Must be an integer in the range of 1-20. The default value is five.

• profile load load_name —Specify the name of the load profile. Must be a string.

• load-calc-frequency load_calc_frequency_value —Specify the system load calculation interval in seconds. Must be an integer in the range of 5-3600. The default value is 10 seconds.

• load-fetch-frequency load_fetch_frequency_value —Specify the time interval in seconds at which the service pods fetch load from the cache pod. Must be an integer in the range of 5-3600. The default value is 10 seconds.

• load-profile profile_name —Specify the name of the load profile.

• overload-profile overload_profile_name —Specify the name of the overload profile.

• profile overload-exclude ovreload_exclude_profile_name : Specify the exclude overload profile name:

  • arp-list list_name_arp : Specify the ARP list that needs to be excluded from throttling decisions. Must be an integer in the range of 1-15. Maximum eight entries are allowed.

  • dnn-list list_name_dnn : Specify the list of DNNs that needs to be excluded from throttling decision. Maximum three entries are allowed.

  • message-priority : Specify upto which message periority to be excluded from throttling decisions.

  • procedure-list : Procedures to be excluded from throttling decisions. This parameter is applicable only for Self-Protection.

  • qci-list list_name_qci : Specify the QoS Class Identifier to be excluded from throttling decisions. Must be an integer in the range of 1-.254. Maximum 8 entries are allowed. For example, range values can be 1-9,65,66,69,70,80,82,83,128-254.