/mcpDescription Setting This field applies if you configured TLS for the incoming and outgoing transport type. For device authentication, enter the name of the Secure Certificate Subject or Subject Alternate Name certificate for the SIP trunk device. If you have a Unified Communications Manager cluster or if you use SRV lookup for the TLS peer, a single trunk may resolve to multiple hosts, which results in multiple Secure Certificate Subject or Subject Alternate Name for the trunks. If multiple Secure Certificate Subject or Subject Alternate Name exists, enter one of the following characters to separate the names: space, comma, semicolon, or a colon. You can enter up to 4096 characters in this field. Tip The subject name corresponds to the source connection TLS certificate. Ensure that subject names are unique for each subject name and port. You cannot assign the same subject name and incoming port combination to different SIP trunks. Example: SIP TLS trunk1 on port 5061 has Secure Certificate Subject or Subject Alternate Name my_cm1, my_cm2. SIP TLS trunk2 on port 5071 has Secure Certificate Subject or Subject Alternate Name my_cm2, my_cm3. SIP TLS trunk3 on port 5061 can have Secure Certificate Subject or Subject Alternate Name my_ccm4 but cannot have Secure Certificate Subject or Subject Alternate Name my_cm1. Secure Certificate Subject or Subject Alternate Name Choose the incoming port. Enter a value that is a unique port number from 0-65535. The default port value for incoming TCP and UDP SIP messages specifies 5060. The default SIP secured port for incoming TLS messages specifies 5061. The value that you enter applies to all SIP trunks that use the profile. Tip All SIP trunks that use TLS can share the same incoming port; all SIP trunks that use TCP + UDP can share the same incoming port. You cannot mix SIP TLS transport trunks with SIP non-TLS transport trunk types on the same port. Tip If the incoming packet rate on a SIP trunk UDP port from a single IP address exceeds the configured SIP Trunk UDP Port Throttle Threshold during normal traffic, reconfigure the threshold. When a SIP trunk and SIP station share the same incoming UDP port, Unified Communications Manager throttles packets based on the higher of the two service parameter values. You must restart the Cisco CallManager service for changes to this parameter to take effect. Incoming Port Security Guide for Cisco Unified Communications Manager, Release 15 and SUs 189 Basic System Security SIP Trunk Security Profile Settings