We support both TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) communication protocols. While UDP is by far the most common of the two protocols TCP is stated to have advantages.
- KeepAlives: SIP must periodically send out keepalives to maintain the NAT table entry. The required frequency of keepalives is much higher for UDP (maybe every 30 seconds) vs TCP (maybe every 15 minutes). While not relevant for small installations TCP has significant advantages within enterprise installations.
- TLS: allows for the secure encrypted transmission of SIP for deployments that require increased security by encrypting the SIP messaging between you and us. On your side, you should connect to tls.l2access.com.au as your proxy/host using TCP port 5061.
- SRTP (Secure Real-Time Transport Protocol or Secure RTP): SRTP encrypts or “codes” the voice data making it impossible to decipher the conversation except for the person who has the decoding “key”, or the person to whom the call is being made.
Step One: TCP, TLS & Secure RTP Options
- Log into your account.
- Click in Switchboard.
- Select your Number.
- Select Preferences.
- TCP, TLS, UDP & SRTP Options.
- Select one of the SIP Transport options.
- Enable Force Calls RTP.
- Click Save settings to update.
Step Two: Change PBX/handset transport.
- Log into IP PBX / Handset.
- Select account.
- Find the option to change Transport > TLS.