> Source: [sk182594](https://support.checkpoint.com/results/sk/sk182594)

# sk182594 - Phones are unable to register to the gatekeeper (H.323)

| Property | Value |
|----------|-------|
| Solution ID | sk182594 |
| Date Created | 2024-08-23 |
| Last Modified | 2024-08-26 |
| Technical Level | Advanced |
| Products | Security Gateway, Scalable Platforms |
| Versions | R81.20, R81.10 (EOS), R81 (EOS), R81.20, R81.10 (EOS) |

## Symptoms

- * Drops are not available either in the logs or in the "fw ctl zdebug + drop".
* Phones are unable to register to the gatekeeper.
* When taking "tcpdumps" on the internal and external interfaces on the firewall, a full TCP handshake on the interface that faces the gatekeeper is seen while on the second interface (which faces the phone) we do not see these packets.
* Disabling "secureXL" did not resolve the issue.
* The TCP connection is being initiated by the gatekeeper and not by the phone.

## Cause

By default, the **H.323** inspection in the firewall expects the phone to initiate the connection and not the gatekeeper; therefore, it is not handling the client-to-server and server-to-client connections correctly.

## Solution

This solution requires authentication. Please log in to view the full solution.

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