[Name] mediadirection [Required] false [Attribute Constraints] If used in conjunction with prepareddialogid , the bridge type must match that used on the previous dialogprepare element. [Type] ECMAScript Expression [Default Value] both [Description] An ECMAScript expression that defines the direction of the media flow between the Dialog and the Connection or Conference. The following values can be used: both Specifies a full duplex connection where the media flows in both directions. dialogtransmit The dialog transmits media to the Connection or Conference but does not receive any media streams. dialogreceive The dialog receives media from the Connection or Conference but does not transmit any media streams. If both the mediadirection and the prepareddialogid are specified and the bridge type specified by the mediadirection attribute does not match that used on the previous dialogprepare element, an error.dialog.notstarted event will be raised. If no value for the mediadirection attribute was specified on the previous dialogprepare element, any mediadirection type option may be specified. [Valid Values] 
both dialogtransmit dialogreceive