SIP configuration
The use of INI files means that most SIP parameters are already correctly configured. For completeness, they are shown again here for the web configuration.
Click on the left in the tree structure on "VoIP | SIP Definitions | General", and check/change the following settings as necessary:
Under "Channel Select Mode", "Cyclic Ascending" is set in order to make use of all channels of the trunk in IP-to-Tel calls.
"Enable Early Media" is set to "Enable", to ensure that you hear tones (alerts etc.) generated by the exchange.
"183 Message Behavior" is set to "Progress".
Under "Session-Expires Time", enter the value "180", so that in the event of network problems the call is terminated after 180 seconds at the latest.
Under "Minimum Session-Expires", set the value to "90".
"Session Expires Method" is set to "UPDATE".
Under "Asserted Identity Mode" "Adding Preferred Identity" is set, so that this header is used for sender number signaling.
Under "Fax Signaling Method" set "T.38 Relay", and under "Detect Fax on Answer Tone" select the entry "Initiate T.38 on Preamble".
"SIP Transport Type" is set as "UDP"; "SIP UDP Local Port" and "SIP TCP Local Port" each as "5080", and "SIP TLS Local Port" as "5081".
You should select these settings even if you don't yet use the SAS application, as they simplify a later migration.
"SIP Destination Port" is set as "5060", and the entries "Use user=phone in SIP URL" and "Use user=phone in From Header" are each set "Yes".
Finally, click at lower right on "Submit" to activate all settings.
