LaunchTelephonyDial to the SIP Endpoint

SIP Call Ladder

Synthflow AI provides a SIP Call Ladder feature, which allows detailed technical analysis of your calls by displaying the SIP signaling flow and allowing you to download packet capture files for deeper investigation.

This tool is useful for:

  • Troubleshooting call failures by examining the SIP signaling at a glance.
  • Understanding call flow between different network elements for full transparency on the Synthflow AI network.
  • Debugging connectivity issues with detailed packet analysis and the ability to download a pcap.
  • Self-service problem resolution without needing to contact support.

Accessing SIP Call Ladder

1

Navigate to the Logs section in your workspace. For more information about Logs you can learn more here

2

Select any call from your call logs to view its details.

3

Click on the SIP Ladder tab to view the SIP signaling diagram.

Understanding the SIP Ladder Diagram

The SIP ladder diagram shows the complete signaling flow between different network elements involved in your call:

  • Vertical lines represent different network elements (your agent, our network hops, SIP carrier)
  • Horizontal arrows show SIP messages flowing between elements
  • Message types include INVITE, 100 Trying, 180 Ringing, 200 OK, BYE, etc.
  • Timestamps help you understand the timing of each signaling event

This visual representation should make it easier to view and debug SIP signaling at a glance, for anything else we provide an option to download the SIP pcap file itself.

Downloading PCAP Files

For advanced troubleshooting, you can download the complete packet capture (PCAP) file for any call. Please be aware you will need a program to view .pcap files, we recommend Wireshark for this.

1

From the SIP Ladder tab, locate the Download PCAP button.

2

Click to download the PCAP file to your local machine.

3

Use tools like Wireshark to analyze the packet capture file for detailed network analysis.

Troubleshooting Common Issues

When analyzing SIP ladder diagrams, look for these common patterns:

IssueSIP Ladder PatternWhat to Check
Call Not ConnectingINVITE sent but no responseCheck the agents number, specifically SIP Domain if you add your own numbers.
Call DropsUnexpected BYE messageCheck for network timeouts or carrier issues
Authentication Failures401 responseVerify SIP credentials and account permissions
Authentication Failures403 responsesVerify SIP credentials and calling permissions
One-Way Audio200 OK received but RTP issuesVerify media codec compatibility, source and destination IP’s and firewall settings

Getting Additional Help

If you’re unable to resolve issues using the SIP ladder and PCAP analysis:

  1. Check the Telephony Errors page for specific error code explanations.
  2. Review your number configuration and the call settings for correct formatting.
  3. Contact support with the PCAP file and SIP ladder screenshot for advanced troubleshooting along with the URL of the agent so we can help.