Play server ringback – off by default and recommended not to change it. When on the voipbox generates own fake ringback tone played from a file. The ringback is sent to voipswitch and to the client. It can be used when a termination gateway for some reason cannot send own ringback tone. In such cases however it is better to leave playing the tone to the client endpoints as most of them can play own local ringback tone on receiving SIP 183 response.

Enable transcoding – allow for transcoding service for the client. For example when the client sends a call in a codec that is not supported by the termination endpoint. The system, in such case, allow for establishing the call with different codecs and automatically puts the stream through the transcoder server.

Calls limit – allows to define the limit it number of concurrent calls the client can make