Ports
To use Cisco WebEx Telepresence, you need to enable TCP port 5061 outbound for Session Initiation Protocol (SIP) communication and TCP port 443 outbound for provisioning and directory services.
For media functionality, WebEx Telepresence devices initiate User Datagram Protocol (UDP) connections by using the following ports:
- Cisco IP Video Phone E20: UDP ports range from 2326 to 2358.
- Codec C series, EX series, MX series, SX series, and VX series devices: UDP ports range from 2326 to 2487.
For both types of devices, the destination port number of the media UDP connections are dynamically assigned, based on SIP Session Description Protocol (SDP) message contents.
Other firewall settings
To ensure the best user experience, disable the SIP ALG (application-level gateway) functionality in your firewall settings so as not to interfere with the proper operation of WebEx Telepresence.
 | Some firewall implementations refer to SIP ALG functionality as VoIP fixup. |
For more information on disabling the SIP ALG feature, see WebEx Telepresence: Firewall requirements for SIP ALG.