> Source: [sk116162](https://support.checkpoint.com/results/sk/sk116162)

# sk116162 - Issues with VoIP through Check Point Security Gateway when using WebEx Expressway Cisco VCS Telepresence

| Property | Value |
|----------|-------|
| Solution ID | sk116162 |
| Date Created | 2017-03-09 |
| Last Modified | 2017-03-13 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- * A VoIP call could be established (after WebEx Telepresence device registers with WebEx SIP server in cloud), but VoIP call drops after 5-10 seconds.

* Traffic capture files from Check Point Security Gateway contain "`ICMP - Destination unreachable (Port unreachable)`" errors.

## Cause

* Bi-directional traffic is not allowed between all required objects for both TCP SIP ports and UDP high ports.

* The predefined SIP services with the predefined Protocol Type are used in the relevant Security rules / NAT rules.

## Solution

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

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