Managing Signaling

Use Signaling settings to define rules for call routing and signaling for special cases. Normally these settings are not required, and their use requires proper understanding of signaling in telecommunication. A tooltip displays the original parameter name when the cursor is placed on the setting text.

In SP04, the former Delayed Connection settings for H.323 gateways were removed as they are replaced by Early Queueing function that can be applied for systems with SIP trunks as well.

  1. On the System Configurator main screen, choose Call Switching > Global Switching Settings > Signaling.
  2. Configure the settings according to the following table.



    Outbound Destination

    Cause Code for Rerouting Calls

    Define cause codes that make the Call Dispatcher to retry call routing to an alternative destination. Can be used in environments with multiple SIP and H.323 trunks. Different devices use different cause codes for informing about insufficient line capacity or congestion; list the codes here to accurately recognize rerouting needs. Enter a comma-separated list of string values, for example 34,44,58.

    Cause Code for Blocked Calls

    Define the cause codes for different trunks that enable the Call Dispatcher to block call routing to the target destination. Codes can be used in environments with multiple SIP and H.323 trunks. Different devices use different cause codes for informing about the line state; list the codes here to accurately recognize a need for temporary blocking. Enter a comma-separated list of string values, such as 48,52.

    Delay for Retries

    Define how soon Call Dispatcher tries to call a destination that has failed earlier. The default value is 3 minutes. If the value is set to 0, the failed destination is not tried again.

    Destination is also reactivated if an inbound call from the destination is detected, or routing information is updated.

    Disable Call Routing Between Trunks

    Select this option to prevent looping between trunks if more than one trunk participate in call routing. For example, if an external trunk and the Call Dispatcher are configured to pass all unrecognized numbers to each other, this can lead to a never-ending loop if an inbound call to a number not known by either CD or external trunk enters the system.

    Handling Unallocated Numbers

    Cause code for Unallocated Number

    Specify the cause code to be used when an inbound call to a nonexisting number is rejected. See also Rerouting Number for Unallocated Numbers. Enter any integer value; the default value is 1.

    Rerouting Number for Unallocated Numbers

    Enter the phone number where the inbound calls to numbers not found in the system’s address space are redirected. For example all inbound calls to invalid numbers can be switched to the switchboard queue. If the number is not defined, and no other rerouting is defined, all these non-allocated calls are rejected.


    If this number is defined, no automatic rerouting to another PSTN target is used.

    Limit Rerouting to Listed Trunks

    Define the trunks, where from calls to nonexisting numbers are routed to a specified Rerouting Number for Unallocated Numbers, other calls are rejected.


    If no trunks are defined, all unallocated calls are rerouted to the specified number.

    Call Identification (CID)

    Note: These settings were for incoming calls using H. 323 protocol and are no longer supported.

    Enable Call Identification

    Select this option to enable using call identification (CID) function.

    CID-Enabled Destinations

    To define the destinations where calls with CID information can be transferred to, enter IP addresses separated with a comma.

    CID-Enabled Extensions

    To define the extensions where calls with CID information can be transferred to, enter the numbers separated with a comma.

    Exceptions in CID-Enabled Extensions

    To define the extensions where calls with CID information cannot be transferred to, enter the numbers separated with a comma.


    Phone Client Plays Ringtones for Outbound Calls

    Define how the terminal component creates ringing tones for outgoing calls. The choices are:

    • For internal calls only.

    • For all calls.

    MRS plays Ringtones to Phone Client for Outbound Calls

    Define if Call Dispatcher should manage playing ringtones for plain outbound calls. If the number of plain outbound calls is high, phone client (terminal) can play the tone itself, and thus lessen the MRS load. In that case, remove the selection, and choose For All Calls option in the Phone Client Plays Ringtones for Outbound Calls setting. MRS plays ringtones only for the trunks in the addresses defined in the IP Address for Trunks Requiring Ringing Tone, see the setting below.

    IP Address for Trunks Requiring Ringing Tone

    Enter IP address of the trunk that require ringing tone from Sinch Contact Pro. To enter several trunk addresses, separate them by comma (,).


    Most trunks can provide the tone themselves, use this setting only when absolutely required.

    Advanced Settings

    Allow Early Queueing

    To enable early queueing, select the checkbox. In addition to this, you must configure a channel, queue or IVR to use early queuing. Added in Sp04.

    Exclude Original B Number from Destination Data

    To save the modified B number in call log as destination data, select the checkbox. Otherwise original B number is saved.

    Use Original Destination In Call Transfers

    Define whether CD should use the original destination when transferring a call. The aim is to improve the sound quality by minimizing trunk-to-trunk streams and signalling. The reuse applies only to Least Recently Used (LRU) routes.

    Block Hold Signal Sending to Trunk

    Select this option to prevent sending the Hold signal to the trunk. SignalHold

    Use Session Progress Message

    Select this option to make desk phones in system capable of handling 183 Progress Session indications. In this case a call from a SIP phone towards a trunk is not automatically connected when the trunk starts progress stream but the progress indication is used to start streaming towards the desk phone.

    Check End Point Address Validity

    Select this option to check if the end point IP address is still the same as when it was registered.

    Route Video Streams

    Select this option to use video ports as well.

    Realm for Authenticating SIP End Points

    Specify the realm used when authenticating the SIP endpoints in the system. The default value is cssrealm.

    Caller Name

    Define how the caller name is sent in transfers or outbound calls. Choices are:

    • Keep Name

    • Remove Name

    • Keep Name for Internal Devices

    • Remove Name in Transfers

    • Use R Number or A Number in Outbound Calls and Transfers

    Use CD-Controlled Transfers

    Enables using the Call Dispatcher controlled transferring operations instead of the bridge controlled call transfers. The parameter can also be given on bridge-level to target only a single SIP bridge. This parameter is mostly needed in cases where the REFER mechanism is not supported on SIP trunks. Setting is disabled by default, but for SIP bridges it is enabled.

    Show Caller and Location

    For advanced used only: Useful when both Visible A number and location-based routing is used. Choose one of the options:

    • Show Original Caller and Location

    • Show Masked Caller but Original Location

    Transfer Call Back if Call Rejected

    Define, if the call is transferred back if it is rejected.

    Max. Waiting Time for IP Phones

    Define the time calls are offered to desk phones. If the desk phone rejects the call, or does not answer it in the time defined here, the call is transferred to voicemail, or another secondary address. The default value is 30 seconds.

    Add Extra Data to Joined Party

    When local calls are joined, possible additional data is passed to application level. To block additional data, remove the selection.

    Allocate MRS Modules of Same Priority (Advanced)

    Define how MRS modules with the same priority value are allocated for tasks.

    • To use all MRS modules in turns, choose Round Robin (the default value).

    • To use entire capacity of one MRS first before starting to use another one, choose Static Order.

    Use Trunk Reporting

    To include routing data of outbound calls in Reporting, choose the appropriate option:

    • No Trunk Reporting

    • Original B Number Reported

    • Modified B Number Reported

    • Original And Modified B Number Reported

    Ongoing Call Assigns Agent to Location

    To assign an agent that is in a call to a location based on the network element used by that call, select the checkbox. The location may define a switching rule, for example add a prefix to the destination number, that causes a specific destination route to be selected. Added in SP04.