> For a complete page index, fetch https://docs.synthflow.ai/llms.txt. For full documentation content, fetch https://docs.synthflow.ai/llms-full.txt.

# SIP Call Ladder

> View SIP ladder diagrams and download PCAP files for call analysis

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

Navigate to the **Logs** section in your workspace. For more information about Logs you can [learn more here](/logs)

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

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

![](https://storage.googleapis.com/granular-changelog/doc-images/sip-ladder-select-tab.png)

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## 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.

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## 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.

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

Click to download the PCAP file to your local machine.

![](https://storage.googleapis.com/granular-changelog/doc-images/sip-ladder-pcap-download.png)

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

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## Troubleshooting Common Issues

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

| Issue                       | SIP Ladder Pattern             | What to Check                                                                       |
| --------------------------- | ------------------------------ | ----------------------------------------------------------------------------------- |
| **Call Not Connecting**     | INVITE sent but no response    | Check the agents number, specifically SIP Domain if you add your own numbers.       |
| **Call Drops**              | Unexpected BYE message         | Check for network timeouts or carrier issues                                        |
| **Authentication Failures** | 401 response                   | Verify SIP credentials and account permissions                                      |
| **Authentication Failures** | 403 responses                  | Verify SIP credentials and calling permissions                                      |
| **One-Way Audio**           | 200 OK received but RTP issues | Verify 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](/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.