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This requires an SSL certificate from a trusted authority. After you install the certificate (Server > HTTPs & Proxy), then TLS/SRTP is found as a SIP Transport option in an extension’s Digium Phone Settings, under the Advanced settings. An organization-level, extended certificate is not required, and a wildcard certificate can be used. But the certificate cannot be self signed, it must come from a trusted authority.
Changing the SIP transport causes the phone to reboot. We recommend that you do this outside of business hours.
If you have remote Sangoma Phones, please see How do I set up my network for Switchvox to ensure that your network environment is configured correctly. Port 5061 must be forwarded to Switchvox.
Only the communication directly between the Sangoma phone and Switchvox is encrypted. The extension's voicemail and call recordings are not encrypted.
Encrypted calls use more hardware resources, so be sure that you have the resources available. Encrypting your calls could use up to 20% more of your hardware resources than unencrypted calling.
Packet captures of encrypted data cannot be used to troubleshoot calling issues. In the event that you are experiencing calling issues, Sangoma Technical Support will first need to configure a Sangoma phone on your Switchvox to use UDP, to narrow down the cause.
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