In order to configure your PBX for your signalling and voice data to be encrypted, your PBX must be able to use SIP over TCP or TLS and support encryption. If you are unsure if your PBX supports encryption, please contact the manufacturer.
In the current stage, your PBX has to support SRV DNS records (_sips._tcp.sipconnect.sipgate.co.uk). Your PBX should automatically switch to secure signalling.
If you're familiar with network sniffing, you'll be able to see the difference between encrypted and non-encrypted signalling.
Please keep in mind that TLS uses port 5061 instead of port 5060 (standard UDP).
We are currently in the process of testing different PBX's operability with secure trunking and plan to release a list of manufacturers in the near future.