Location Service consists of the following layers as part of the non-roaming location services architecture:

• UE: The UE represents end-user devices, such as smart phones, tablets, or IoT devices. These devices interact with the network.

• GMLC: GMLC provides the location information services related to mobile devices.

• LCS Client: The LCS client is an external entity or application that requests location information for a specific mobile device.

• LRF: The LRF is a component within the Location Services (LCS) architecture in cellular networks. LRF retrieves and provides the location information for mobile devices or user equipment (UE).

• LMF: The LMF determines the geographical location of the UE.

• AMF: The AMF is a key component in 5G networks. It manages mobility, session management, and security for user devices.

• UDM: The UDM handles user-related data, including authentication, authorization, and subscription information.

• RAN: The RAN connects user devices to the core network. It includes base stations and antennas.

• N1 Interface: The N1 interface connects the UE and the RAN. It carries user data and control signaling.

• N2 Interface: The N2 interface connects the AMF and the RAN. It handles signaling and data transfer between the core network and the RAN.

• NL1 Interface: NL1 interface connects the LMF to the UE.

• NL2 Interface: NL2 interface connects the AMF to the GMLC.

The following diagram describes the high level architecture for location services.

This section describes the key call flows for this feature.

To configure LMF in the network element profile list, use the following configuration:

config 
    amf-global 
        operator-policy policy_name 
            ccp-name ccp_name 
               network-element-profile-list lmf lmf_name 
               end 

NOTES:

• ccp-name ccp_name —Specify the Configuration Control Point (CCP) name. The CCP is used for managing and controlling configuration settings.

• network-element-profile-list lmf lmf_name —Specify the name of LMF with the network element profile.

To configure the profile NF-client, use the following configuration:

config 
    profile nf-client nf-type nf_client_name 
        lmf-profile lmf_profile_name 
            locality locality_name 
                priority priority_value 
                service name type nlmf-loc 
                    endpoint-profile profile_name 
                        capacity capacity_value 
                        default-notification-subscriptions  subscriptions_name  
                           n1-message-class  n1_message_class_type  
                           notification-type  notification_message_type  
                           callback-uri  callback_uri_url  
                           uri-scheme uri_scheme_name 
                           version 
                           uri-version uri_version 
                           endpoint-name end_point_name 
                           priority priority_value 
                           primary ip-address ipv4 ipv4_address 
                           primary ip-address port ipv4_port_number 
                           end 

NOTES:

• profile nf-client nf-type nf_client_name —Specify the profile name of the NF client.

• lmf-profile profile_name —Specify the profile name for the NSSF.

• locality locality_name —Specify the locality name within the NSSF profile.

• priority priority_value —Specify the priority value of the locality name within the NSSF profile.

• endpoint-profile profile_name —Specify the associated end point profile name.

• capacity capacity_value —Specify the capacity of the endpoint.

• default-notification-subscriptions default_notification_subscriptions_name —Specify the name of the default notification subscriptions.

• n1-message-class n1_message_class_type —Specify the n1 message class.

• notification-type notification_message_type —Specify the type of notification message.

• callback-uri callback_uri_url —Specify the URL for the callback uri.

• uri-scheme uri_scheme_name —Specify the uri scheme associated with the endpoint.

• uri-version uri_version —Specify the uri version associated with the endpoint.

Configuration Example

Following is an example configuration.

profile nf-client nf-type lmf
 lmf-profile LMF1
  locality LOC1
   priority 30
   service name type nlmf-loc
    endpoint-profile EP1
     capacity   30
     uri-scheme http
     endpoint-name EP1
      priority 56
      capacity 100
      default-notification-subscriptions <name>
       n1-message-class LCS/LPP
       notification-type N1_MESSAGES
       callback-uri <URL>
       exit
      primary ip-address ipv4 172.16.186.13
      primary ip-address port 8047
     exit
    exit

To configure the profile network element, use the following configuration:

config 
 profile network-element lmf lmf_name 
  nf-client-profile nf_client_name 
  failure-handling-profile failure_handling_profile_name 
  end 

NOTES:

• profile network-element lmf lmf_name —Specify the profile name for the network element.

• nf-client-profile nf_client_name —Specify the network function client profile name.

• failure-handling-profile failure_handling_profile_name —Specify the failure handling profile name.

To configure the profile NF-client-failure, use the following configuration:

config 
    profile nf-client-failure nf-type nssf lmf_name 
        profile failure-handling failure_handling_profile_name 
            service name type nlmf-loc 
                responsetimeout timeout_value 
                    message type LmfDetermineLocation 
                        status-code httpv2 503 
                        retry retry_count 
                        action retry-and-ignore 
                        end 

NOTES:

• profile nf-client-failure nf-type lmf nssf_name —Specify NF client failure profile.

• profile failure-handling failure_handling_profile_name —Specify failure-handling profile name.

• responsetimeout timeout_value —Specify the response timeout for the specified services.

• retry retry_count —Specify the retry count for the status code.

The following is an example configuration.

profile nf-client-failure nf-type lmf
 profile failure-handling FH1
  service name type nlmf-loc
   responsetimeout  10
   message type LmfDetermineLocation
    status-code httpv2 403
     retry  3
     action retry-and-continue
    exit
   message type LmfN1MessageNotify
     status-code httpv2 403
     retransmit          3
     retransmit-interval 2000
     action retry-and-continue
    exit
   message type LmfN2InfoNotify
     status-code httpv2 403
     retransmit          3
     retransmit-interval 2000
     action retry-and-continue
    exit
   exit
  exit
 exit
exit

To configure the profile NF-pair NF-type, use the following configuration:

config 
    profile nf-pair nf-type nf_type_name 
        locality client client_name 
        locality preferred-server server_name 
        locality geo-server server_name 
        end 

NOTES:

• profile nf-pair nf-type nf_type_name —Specify NF (Network Function) type name.

• locality client client_name —Specify the locality name for the client.

• locality preferred-server server_name —Specify the server name as the preferred server locality.

• locality geo-server server_name —Specify the geographical location for the geo-server.

Note

Each endpoint-profile can contain multiple endpoints. Each endpoint contains defaultNotificationCallback under endpoint-name. So, instead of configuring primary and secondary within one endpoint, it is advisable to configure them under different endpoint names in an endpoint profile to ensure separate defaultNotificationCallback for each endpoint.

The following statistics are supported for the MTLR Location Services feature.

LMF STATS Under nl1_service_stats

Following are the LMF STATS records under nl1_service_stats.

Following are the examples of stats output:

• nl1_service_stats{app_name="AMF",cluster="clu1",data_center="dc1",instance_id="0",
  message_type="NlmfN1N2MessageTransferReq",reason="",roaming_status="HOMER",
  service_name="amf-service",slice_data="_2-333333",status="success"} 2

• nl1_service_stats{app_name="AMF",cluster="clu1",data_center="dc1",instance_id="2",
  message_type="NlmfN1N2MessageTransferReq",reason="Invalid Input",roaming_status="HOMER",
  service_name="amf-service",slice_data="_2-333333",status="failures"} 2

• nl1_service_stats{app_name="AMF",cluster="clu1",data_center="dc1",instance_id="2",
  message_type="NlmfN1N2MessageTransferReq",reason="Invalid LCS Correlation ID",roaming_status="HOMER",
  service_name="amf-service",slice_data="_2-333333",status="failures"} 3

• n11_service_stats{app_name="AMF",cluster="clu1",data_center="dc1",instance_id="2",
  message_type="NlmfN1N2MessageTransferfailurenotifyReq",reason="",
  roaming_status="HOMER",service_name="amf-service",slice_data="_2-333333",status="success"} 3

• n11_service_stats{app_name="AMF",cluster="clu1",data_center="dc1",instance_id="2",
  message_type="NlmfN1N2MessageTransferfailurenotifyRsp",reason="",roaming_status="HOMER",
  service_name="amf-service",slice_data="_2-333333",status="success"} 3

• nl1_service_stats{app_name="AMF",cluster="clu1",data_center="dc1",instance_id="0", 
  message_type=" NlmfNonUEN2MessageTransferRequest ", reason="", roaming_status=" ", 
  service_name="amf-service", slice_data="", status="success"} 1

GMLC STATS Under nl2_service_stats

Following are the GMLC STATS records under nl2_service_stats.

Following is the example of stats output:

nl2_service_stats{app_name="AMF",cluster="clu1",data_center="dc1",instance_id="0",
message_type="NgmlcProvidePositiongInfoRsp",reason="",roaming_status="HOMER",
service_name="amf-service",slice_data="_2-333333",status="success"} 1

NGAP Service Stats Under n2_service_stats

Following are the NGAP service stats records under n2_service_stats

Following is the example of stats output:

n2_service_stats{app_name="AMF",cluster="clu1",data_center="dc1",instance_id="0",
message_type="DlUeAssociatedNRPPaTransport",reason="",roaming_status="HOMER",
service_name="amf-service",slice_data="_2-333333",status="success"} 1

n2_service_stats{app_name="AMF",cluster="clu1",data_center="dc1",instance_id="0", 
message_type=" DlNonUeAssociatedNRPPaTransport ",reason="", roaming_status="", service_name="amf-service", 
slice_data="",status="success"} 1

Nas Message Total

Location service based UplinkNasTransport and DownlinkNasTransport is recorded under message type N1DlNasTransport_LPP, N1UlNasTransport_LPP.

Following is the example of stats output:

amf_nas_message_total{app_name="AMF",cluster="clu1",data_center="dc1",instance_id="0",
message_direction="outbound",message_type="N1DlNasTransport_LPP",
service_name="amf-service",slice_data="_2-333333"} 2