/mcpWhen a shared line is involved in the secure conference, the phone that has its line in RIU (remote in use) mode will not show a security status for the call. However, TSP exposes the overall security status to the application along with other call information for the inactive call. This means that TSP also reports the OverallSecurityStatus to all RIU lines. The status will match what is reported to the active line. Applications can decide whether to expose the information to the end user. Secure RTP The secure RTP (SRTP) feature allows Cisco TSP to report SRTP information to application as well as allow application to specify SRTP algorithm IDs during device registration. The SRTP information that Cisco TSP provides will include master key, master salt, algorithmID, isMKIPresent, and keyDerivation. To receive those key materials, administrator needs to configure TLS Enabled and SRTP Enabled flag in Unified Communications Manager Admin User windows and establish TLS link between TSP and CTIManager. Besides, during device registration, application can provide SRTP algorithm IDs for CTI port and CTI Route Point in case of media termination by application. Application should use new Cisco extension for Line_devSpecific -CciscoLineDevSpecificUserSetSRTPAlgorithmID to set supported SRTP algorithm IDs after calling LineOpen with 0x80070000 version or higher negotiated, then followed by either CCiscoLineDevSpecificUserControlRTPStream or CciscoLineDevSpecificPortRegistrationPerCall to allow TSP to open device on CTI Manager. When call arrives on an opened line, TSP will send LINE_CALLDEVSPECIFIC event to application with secure media indicator; then, application should query LINECALLINFO to get detail SRTP information if SRTP information is available. The SRTP information resides in the DevSpecific portion of the LINECALLINFO structure. In case of mid-call monitoring, Cisco TSP will send LINE_CALLDEVSPECIFIC with secure media indicator, however there will be no SRTP information available for retrieval under this scenario. The event is only sent upon application request via PhoneDevSpecific with CPDST_REQUEST_RTP_SNAPSHOT_INFO message type. To support SRTP that is using static registration, a generic mechanism for delayed device/line now exists. The following ones apply: • Extension version bit SELSIUSTSP_LINE_EXT_VER_FOR_DELAYED_OPEN = 0x40000000 • CiscoLineDevSpecificType -SLDST_SEND_LINE_OPEN • CCiscoLineDevSpecific -CciscoLineDevSpecificSendLineOpen If application negotiates with 0x00070000 in lineOpen against CTI port, TSP will do LineOpen/DeviceOpen immediately. If application negotiates with 0x40070000 in LineOpen against CTI port, TSP will delay the LineOpen/DeviceOpen. Application can specify SRTP algorithm ID by using CciscoLineDevSpecificUserSetSRTPAlgorithmID (SLDST_USER_SET_SRTP_ALGORITHM_ID). However, to trigger actual device/line open in TSP, application needs to send CciscoLineDevSpecificSendLineOpen(SLDST_SEND_LINE_OPEN) If application negotiates with 0x80070000 in LineOpen against CTI port/RP, TSP will delay the LineOpen/DeviceOpen until application specifies media information in CCiscoLineDevSpecific; however, application can use CciscoLineDevSpecificUserSetSRTPAlgorithmID (SLDST_USER_SET_SRTP_ALGORITHM_ID) to specify SRTP algorithm ID before specifying the media information. Cisco Unified TAPI Developers Guide for Cisco Unified Communications Manager, Release 15 and SUs 88 Features Supported by TSP Secure RTP