Troubleshooting for connecting SIP gateways

Connection requirements

XCC configuration

The XPhone Call Controller (XCC) is a soft switch or medium controller that is seamlessly integrated in the XPhone Connect environment. The SIP gateways for the conference and AnyDevice service are set up on this soft switch. The XPhone Call Controller is installed with the XPhone Connect Server. It communicates with the PBX via SIP trunks and with XPhone Connect via TCP.

As a general rule, the XCC is deactivated.

First of all, the XCC must be activated. To do this, edit the XCC under System settings > Telephony & Meetings > Telephony > SIP:

Uncheck Deactivated, the XCC service is started by default on localhost and the Port 8021. The firewall at the server must approve the connection at the respective port.

After saving the XCC settings, the XCC status changes to green. Activation of the XCC can take a few minutes.

Create an SIP gateway

A new SIP gateway needs to be created for connection to the corresponding telephone system. Do this by adding a new SIP trunk:

The corresponding data on the SIP gateway must be filed in the editing mask:

Gateway type:

The corresponding telephone system is selected here (e.g. Siemens HiPath 3000).

Name:

Enter a unique name here.

Dialling parameter:

Select a dialling parameter.

XCC gateway IP address:

Local XCC IP address which must be filed as the target IP address in the telephone system.

Hint

Please note that when using the fax or voicemail function via XCAPI, either a different IP address (which needs to be set up on the XPhone Connect Server computer) or an alternative port must be used for the XCC SIP trunk as XCAPI also runs on Port 5060. The alternative port must also be configured in the SIP trunk in the PBX.

XCC gateway port:

Default port value: 5060

• Listener port for the SIP messages from the PBX. This port must be filed in the SIP trunk in the PBX.

Hint

Please note that when using the fax or voicemail function via XCAPI, either a different IP address (which needs to be set up on the XPhone Connect Server computer) or an alternative port must be used for the XCC SIP trunk as XCAPI also runs on Port 5060. The alternative port must also be configured in the SIP trunk in the PBX.

PBX IP address:

The PBX IP address makes the SIP trunk available.

PBX port:

Default port value: 5060

• PBX listener port for the SIP trunk set up.

Protocol:

Transmission protocol to be used (UDP or TCP)

• CLIP No Screening:

  To which SIP Header should the CLI (Calling Line Identification) be transferred enabling the PBX to read out and/or process the corresponding value.

AnyDevice:

To enable all users to use a standardised number for forwarding to AnyDevice, the telephone system used must support communication of the forwarding user’s phone number in the SIP Diversion Header or in the History Header. This header is used to identify the participant originally called. To do this, activate this check box: “Standardised telephone number …”.

Telephone number for forwarding:

Enter the telephone number for forwarding; this telephone number must be configured in the telephone system and firmly routed to the XCC. If a user later activates the AnyDevice function on his XPhone Connect Connect Client, his extension is automatically forwarded to the telephone number entered here.

Advanced settings:

For the XCC gateway, the virtual participant’s telephone number can be saved as the call forwarding destination. XccGlobalVirtualFollowMeUserNo = 999

A name (e.g. “Follow-Me”) can be stored in the PBX for the virtual participant, e.g. 999, enabling this name to be shown in the end device display when calls are forwarded. The virtual participant must be forwarded to the actual AnyDevice number.

Conference:

You can enable dial-in conferences here by activating the checkbox.

You can enable dial-in conferences here by activating the check box. Allocate an extension number that can be dialled externally and internally and firmly allocate it to a language. Please note the other conference call server settings required in Set up the conference call server.

After saving the settings, the XCC gateway is automatically started and the status should then change to green:

Set up the conference server

The conference call service phone numbers have already been saved in the SIP gateway’s configuration interface. The phone numbers have been allocated to the corresponding languages. Additional configurations are required to ensure that the conference call server is fully available.

Activate the conference call service

Navigate to System settings > Telephony & Meetings > Meetings. The conference service must be activated:

Activate conference call service for the respective location

The Conference call service at the respective location must be activated in User management. Do this by adapting the Settings in Telephony:

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Activate logging

The corresponding log files are always required for error analysis. One essential advantage is the ability to read the network communication. Recording network traffic on the network card requires the Npcap driver. It can be found under Tools in the XPhone Connect Server’s installation directory.

The corresponding logging can be started via the administration in XPhone Connect Server. The corresponding log levels can be set under System settings > Logging > Telephony gateways.

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After saving the log level settings, the log files are written in the respective file path.

Information from the XPhone Call Controller log

The XPhone Call Controller log file can provide the following information, for example:

• AnyDevice destinations set for individual users

• Follow-Me for inbound calls.

• Call setup for outbound calls.

• XCC service status.

Information from the XCC gateway log

The XCC gateway log file can provide the following information, for example:

• Status of the AnyDevice lines.

• Creating network traces using Npcap.

• Status of the XCC gateway.

Function check

XPhone Call Controller status

The XCC status can be read out via the diagnosis. Furthermore, the log files can provide information on the actual XCC.

To diagnose the XCC, the XPhone Call Controller must be highlighted under System settings > Telephony & Meetings > Telephony > SIP and Diagnosis selected:

The XPhone Call Controller status can be examined in the next window:

SIP gateway status

The SIP gateway status can be read out via the diagnosis. Furthermore, the log files can provide information on the actual SIP gateway.

For the diagnosis of the XCC, the corresponding SIP gateway must be marked under System settings > Telephony & Meetings > Telephony > SIP and the Diagnosis must be selected:

The gateway status can be examined in the diagnosis window: A SIP gateway receives green, connected status when the PBX or remote trunk answers the SIP OPTION request sent by the XCC with SIP-200-OK.

Hint

If the SIP gateway’s dialling parameters are changed, the SIP gateway must be restarted in order to activate the new dialling parameter. Do this using the Restart connection to SIP trunk button.

Troubleshooting for SIP gateway status

Test environment:

Setting up another Log_Test SIP gateway with a gateway address (PBX) which is not available.

There are several ways of analysing this.

Check the XCC gateway’s log files

If the Npcap has been installed, it helps to look at the network version (WPCAP):

It can be seen that only the SIP request to the IP address of the PBX (192.168.110.220) is sent. The response from the PBX is missing.

Unlike the functioning XCC gateway:

The readability of a Npcap file is greatly simplified by the use of Wireshark. The Npcap file can be opened during the debug process with Wireshark, but new messages are not displayed. The file must be opened again for this. The log files can be found in the XPhone Connect Server directory under the path <XPhone Connect Server>\Telephony\Log\.

The example depicts the connection in a 192.168.0.0/16 network:

Check the XPhone Call Controller’s log files

In both cases, the connection between the SIP gateway and the telephone system needs to be checked:

• Correct entry of the IP addresses.

• Ports for SIP communication.

• Check the IP routing between XPhone Connect Server and PBX.

• Check the firewall between XPhone Connect Server and PBX.

Check call routing at the SIP gateway

Setup for testing an inbound call

The SIP gateway must be connected so that the inbound call can be tested. Furthermore, the AnyDevice phone number must be set up in the PBX and AnyDevice must be approved for the users in the location settings. The test user also requires a configured AnyDevice line.

Setup at the Connect Client

In the Connect Client, the AnyDevice destination must be defined in device management and then activated.

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Finished setting up the AnyDevice destination; the test calls and user’s landline number can be started.

Check setup in logging

Check logging of inbound calls

Incoming calls can be checked in the XPhone Call Controller log files where the log outputs are depicted in plain text:

Test scenario:

• The user with extension 195 has saved the AnyDevice destination 187 using Follow-Me.

• AnyDevice call forwarding destination: 2644

• Inbound call from extension 254 to 195 with forwarding to the AnyDevice destination 187:

Troubleshooting for routing inbound calls

Incorrect entry of the AnyDevice destination:

In this case, 00171187187187 was entered as the AnyDevice phone number. The dialling parameters automatically cause the external line to be added, thereby attempting to set up a call to the following number: 000171187187187. This number can not be dialled with the result that this call is ended with the message Originator_Cancel (Originator = PBX).

No call to be seen in the log

This requires checking the routing in the PBX. Call forwarding to the AnyDevice phone number is set at the device. This requires adapting the routing in the PBX which accesses forwarding to the trunk to the SIP gateway.

The firewall can also block any required ports. The port set for SIP communication and the RTP ports (30000 – 31000) for media streaming must therefore be approved.

Checking/Adjusting the phone number format

Where can the phone number be seen in the log file?

In the XCC log file, phone numbers can be analysed for outbound/inbound calls.

Example:

• The user with extension 195 has saved the AnyDevice destination 187 using Follow-Me.

• AnyDevice call forwarding destination: 2644

• Inbound call from extension 254 to 195 with forwarding to the AnyDevice destination 187:

Explanation:

1. Set the AnyDevice destination with activated Follow-Me

2. Incoming call from +4989840798254, forwarded to 2644 (AnyDevice forwarding number)

3. Diversion header (phone number forwarded) and anticipated value

4. AnyDevice destination

5. Confirmation that AnyDevice is ringing

How can phone number conversion be adapted?

In most cases, it is recommended that new dialling parameters are used for a SIP gateway and not those from the CTI gateway.

Everything else is handled through the SIP gateway dialling parameters as is already the case for CTI. The XCC has its own number converter which uses the XPhone Connect Server dialling parameter settings of the corresponding gateway.

Individual cases always need to be considered separately. This requires the corresponding XCC and XCC gateway log files as well as an exact description of the test.

DTMF analysis and troubleshooting

Problem

Despite correct protocol negotiation between XCC and PBX via SDP, it is possible that the PBX passes on the outbound DTMF signals (RTP event as per RFC 2833) incorrectly. Then the signals are not detected by the XCC and there is no reaction to DTMF entries.

Reason

The SDP header contains the incorrect DTMF payload type after protocol negotiation. The default XCC value for the DTMF payload type is 98. It can happen that the PBX does not support this payload type or it sends the RTP events with a different payload type.

Solution

The parameter XccDtmfPayloadType allows manual correction of the transmitted payload type, the DTMF signals are recognized correctly again. This parameter can be set in the Advanced settings of the SIP gateway.

The payload type to be inserted there is established as follows (see also example below):

1. Determine call direction (inbound or outbound)

2. Determine sender of DTMF signals (AnyDevice or conversation partner)

3. Create network trace and evaluate (Npcap, Wireshark)

4. Determine payload type in the SIP message (depends on the call direction in INVITE or 200 OK)

5. Filter RTP events with udp.dstport == <Port> && ip.dst == <IP-Adresse> && rtpevent

6. Determine payload type in the RTP event

7. If necessary, correct payload type for the XCC (XccDtmfPayloadType parameter)

Example on how to proceed

Situation:

• Outbound call by AnyDevice

• DTMF is sent from AnyDevice

• DTMF payload type to be checked

Procedure:

1. Negotiating the DTMF payload type in the SDP header:

   In this case, the SDP header from the SIP message 200 OK of the first call leg is analysed (AnyDevice side). A payload type (Media Format) of 98 was negotiated here; the default value of the XCC.

   

2. Determine RTP events of DTMF signals:

   Via a filter rule in Wireshark, the DTMF signals sent from AnyDevice are listed.

   

3. Determine payload type of RTP events:

   Select one of the RTP events filtered above and import the payload type in the area below. The payload type is also 98 here and therefore determined correctly.

   

4. If the two determined types do not match, this can be corrected via the XccDtmfPayloadType parameter in the Advanced settings of the SIP gateway. For this purpose, the payload type of the PBX determined in step 1 is passed on to the XCC via XccDtmfPayloadType and corrected there.

Information from the XCC gateway log

The XCC gateway log file can provide the following information, for example:

• Status of the AnyDevice lines.

• Creating network traces using Npcap.

• Status of the XCC gateway.

Activate logging

The corresponding log files are always required for error analysis. One essential advantage is the ability to read the network communication. Recording network traffic on the network card requires the Npcap driver. It can be found under Tools in the XPhone Connect Server’s installation directory.

The corresponding logging can be started via the administration in XPhone Connect Server. The corresponding log levels can be set under System settings > Logging > Telephony gateways.

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After saving the log level settings, the log files are written in the respective file path.

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