Application Parameters

LHO-SCP Application Configuration

Top-level per-instance application parameters are defined in the parameters section of the LHO-SCP configuration. Each parameter must have a name and a value.

A sample application parameters configuration might be:

    <application name="<application instance name>" module="LhoScpApp">
      ...
      <parameters>
        <parameter name="trace_level" value="1" />
        <parameter name="trace_level_max" value="1" />
        <parameter name="trace_per_second" value="1" />
        <parameter name="retention_count" value="20" />
        <parameter name="edr_enabled" value="1" />
        <parameter name="edr_app_name" value="EDR" />
        <parameter name="default_edr_stream_key" value="n2lho" />
        <parameter name="default_logic_app_name" value="ACD-LOGIC" />
      </parameters>
      ...

Configuration Details

The available parameter types for a LHO-SCP Application instance are:

Attribute Type Description
parameters Array Array of name = value Parameters for this Application instance.
"trace_level" Integer Set to 1 to enable DEBUG tracing associated with call processing.
Set to 2 to enable DUMP tracing associated with call processing.
Set to 3 to enable SPAM tracing associated with call processing.
The DEBUG setting should be used with caution in a high-traffic environment, as it will cause additional system loading and reduce overall processing capability.
The DUMP and SPAM settings should not be used in a high-traffic environment.
(Default = 0, do not activate tracing).
"trace_level_max" Integer This is a hard cap for trace level enabled dynamically during operation, e.g. via tracing traps or via dynamic change to trace_level using the administration GUI.
This is intended to protect production systems from excessive tracing overheads.
It is determined at startup time and cannot be modified.
Set 0 = none, 1 = debug, 2 = dump, 3 = spam.
(Default = one level higher than the initial value of trace_level)
"trace_per_second" Integer The maximum number of instances for this application which may have their instance trace log enabled in any given second. If this value is reached, then subsequent requests to activate tracing will be ignored until the start of a new clock second.
Values above 1 should be used with care in production systems.
(Default = 1)
"retention_count" Integer The number of most-recent traced dialogs to retain in-memory for monitoring.
(Default = 50).
"edr_enabled" YES / NO / 1 / 0 Should EDR file-writing be enabled?
(Default = NO, do not write EDR files).
"edr_app_name" String Name of the EdrApp application which will perform the write-to-disk for EDRs.
(Default = EDR)
"default_edr_stream_key" String The default EDR stream key that will be used for any EDRs generated by this application.
Most applications will use this default EDR stream key. However, custom service logic or custom configuration may use an alternate stream key.
All EDRs written to the same stream key and processed by the same EdrApp will be interleaved within one file.
The target EdrApp must be explicitly configured to expect the exact stream key.
(Default = [Varies per Application])
"min_grant_secs" 2 - 120 The shortest grant (in seconds) which the service logic (typically instructed by the external OCS) will be permitted to apply in real-time. Any attempt by the service logic (or OCS) to use a lower value thyan this will cause the charged call processing to be aborted.
Very short grant periods will cause significantly increased call processing overheads. The shortest allowable grant period must be at least one second higher than the configured `service_logic_ms` processing window.
(Default = 5 seconds).
"service_logic_ms" 10 - 5000 The limit (in milliseconds) in which service logic must perform its processing and control decisions for real-time SCP call control. This must be sufficiently large to allow for access to external entities, e.g. Database Lookup, Diameter Requests, etc.
This value must be at least 1000 milliseconds lower than the configured `min_grant_secs` to avoid the possibility of service logic taking longer to process than the grant duration.
(Default = 3500 milliseconds).
"correlation_id_ms" 10 - 5000 The limit (in milliseconds) in which the SigtranApp must return our correlation ID when we request one for including in the EstablishTemporaryConnection for an off-switch SRP interaction.
(Default = 1500 milliseconds).
"default_tcap_immediate_ms" 10 - 5000 The limit (in milliseconds) within which an "immediate" TCAP component must arrive after another message. For example, at the end of a call we expect any of the following applicable components (CallInformation, EventReportBCSM, ApplyChargingReport) to arrive "immediately" one after the other.
Individual SSP models may override this value.
(Default = 500 milliseconds).
"default_tcap_margin_ms" 10 - 5000 The grace period (in milliseconds) within which a medium/long-term expected TCAP component may arrive late because of allowance for processing and network time.
Specifically for SSP it allows an (Answer/NoAnswer) EventReportBCSM to arrive slightly after the applicationTimer timeout.
For SSP it also allows the first message at the end of the call (e.g. ApplyChargingReport, EventReportBCSM, or CallInformationReport) to be slightly later than the aChBillingChargingCharacteristics contents strictly specify.
For an SRP definition, this parameter adds a margin on top of max_pa_secs or max_pacui_secs to allow for network/processing delay.
Individual SSP models may override this value.
Individual SRP definitions may override this value.
(Default = 3000 milliseconds).
"default_max_monitored_call_secs" 300 - 7200 The is the permitted maximum duration of a "Monitored", which is a call which uses Disconnect ERBCSM to monitor the duration of the call but which does not use the "Charged" call mechanism to perform initial/extension grants.
A Monitored call may use CallInformationReport and or ActivityTest, but in any case this maximum duration still applies.
Individual SSP models may override this value.
(Default = 7200 seconds).
"default_max_charged_call_secs" 300 - 86400 This is the maximum total granted talk time that the SCP layer will ever permit for a "Charged" call either using ApplyCharging or the CAMEL1 alternative using only ActivityTest. If the service logic (typically instructed by the OCS) attempts to grant a call longer than this duration, the SCP layer will truncate the grant to the configured duration and forcibly terminate the call when that time expires.
Individual SSP models may override this value.
(Default = 86400 seconds).
"default_ac_crossover_ms" 10 - 5000 The limit (in milliseconds) within which an "immediate" TCAP component must arrive after another message. For example, at the end of a call we expect any of the following applicable components (CallInformation, EventReportBCSM, ApplyChargingReport) to arrive "immediately" one after the other.
Individual SSP models may override this value.
(Default = 500 milliseconds).
"default_activity_test_result_ms" 10 - 5000 The limit (in milliseconds) within which an "immediate" TCAP component must arrive after another message. For example, at the end of a call we expect any of the following applicable components (CallInformation, EventReportBCSM, ApplyChargingReport) to arrive "immediately" one after the other.
Individual SSP models may override this value.
(Default = 1000 milliseconds).
"default_max_pa_secs" 5 - 3600 This is the maximum time allowed duration of interaction resulting from sending PlayAnnouncement to this (on-switch or external) SRP. The SRP connection will be aborted if SpecializedResourceReport is not received within this time.
The additional global TCAP round-trip allowance tcap_margin_ms will be added to this value.
Individual SRP definitions may override this value.
(Default = 300 seconds).
"default_max_pacui_secs" 5 - 3600 This is the maximum time allowed duration of interaction resulting from sending PromptAndCollectUserInformation to this (on-switch or external) SRP. The SRP connection will be aborted if PromptAndCollectUserInformationResult is not received within this time.
The additional global TCAP round-trip allowance tcap_margin_ms will be added to this value.
Individual SRP definitions may override this value.
(Default = 300 seconds).
"default_max_etc_ms" 10 - 5000 This is the maximum time that the SCP layer will allow between sending EstablishTemporaryConnection to the SSP and receiving AssistRequestInstructions from the SRP. The SRP connection process will be aborted if the ARI is not received within this time window.
Individual SRP definitions may override this value.
(Default = 4000 milliseconds).
"edr_initialdp_key" 0 / 1 / yes / no Include the IDP_KEY field in EDRs?
(Default = 0, not included).
"edr_initialdp_extended" 0 / 1 / yes / no Include extended InitialDP fields in INITIALDP event EDRs?
(Default = 0, not included).
"default_logic_app_name" String [Required] The configured N2SVCD name for the LogicApp application to which we will hand-off call control. (Default = SCP-LOGIC).