/mcpA new Cisco CallManager service parameter, CTI Report Ringback on SIP 183 with SDP, has been added to configure this feature. When this sevice parameter is set to True, the above behavior applies. This is the default setting. If an application needs to use the legacy behavior, you can set the service parameter to False. Under this setting, if the call gets transferred over a gateway or trunk, Cisco TAPI will report a PROGRESSING state when Cisco Unified Communications Manager recieves a SIP 183, but after a connection is established, Cisco TAPI does not report the CONNECTED state. Secure Conference Prior to release 6.0(1), the security status of each call matched the status for the call between the phone and its immediately connected party, which is a conference bridge in the case of a conference call. No secured conference resource existed, so secure conference calls were not possible. Release 7.0(1) supports a secured conference resource to enable secure conference. The Secure Conference feature lets the administrator configure the Conference bridge resources with either a non-secure mode or an encrypted signaling and media mode. If the bridge is configured in encrypted signaling and media mode, the Conference Bridge will register to Unified Communications Manager as a secure media resource. This enables the user to create a secure conference session. When the media streams of all participants who are involved in the conference are encrypted, the conference exists in encrypted mode. Otherwise, the conference exists in non-secure mode. The overall conference security status depends on the least-secure call in the conference. For example, suppose parties A (secure), B (secure), and C (non-secure) are in a conference. Even though the conference bridge can support encrypted sRTP and is using that protocol to communicate with A and B, C remains a non-secure phone. Thus, the overall conference security status is non-secure. Even though the overall conference security status is non-secure, because a secure conference bridge was allocated, all secure phones (in this case, A and B) will receive sRTP keys. TSP informs each participant about the overall call security status. The system provides the overall call security level of the conference to the application in the DEVSPECIFIC portion of LINECALLINFO to indicate whether the conference call is encrypted or non-secure. The Secure Conference feature uses four fields to present the call security status: DWORD CallSecurityStatusOffset; DWORD CallSecurityStatusSize; DWORD CallSecurityStatusElementCount; DWORD CallSecurityStatusElementFixedSize; The offset will point to following structure: typedef struct CallSecurityStatusInfo { DWORD CallSecurityStatus; } CallSecurityStatusInfo; The system updates LINECALLINFO whenever the overall call security status changes during the call because a secure or non-secure party joins or leaves the conference. A conference resource gets allocated to the conference creator based on the creator security capability. If no conference resource with the same security capability is available, the system allocates a less-secure conference resource to preserve existing functionality. Cisco Unified TAPI Developers Guide for Cisco Unified Communications Manager, Release 15 and SUs 87 Features Supported by TSP Secure Conference