Understanding rfc2833-mode parameter

Hi All,

 

we noticed a strange behavior on the SBC regarding the rfc2833 which is agreed between two sites and now we're trying to understand what the rfc2833-mode=transparent exactly does.

 

On the SBC we had the default configuration on session agents (rfc2833-mode=none / rfc2833-payload=0) and on the signaling interface (rfc2833-mode=transparent / rfc2833-payload=101).

 

According to the documentation "transparent—does not add RFC 2833 telephone-event into SDP if not present, and does not prefer." but now we would like to know what happens when there was already rfc2833 in the SDP, would the SBC change the payload type to 101 in case that it came in with another payload type, not 101?