/mcpConfiguration Description AS-SIP Feature Transport Layer Security (TLS) provides secure and reliable signaling and data transfer between two systems or devices, by using secure ports and certificate exchange. For more information to configure TLS, see the "TLS Setup" chapter in the Security Guide for Cisco Unified Communications Manager. Transport Layer Signalling (TLS) The V.150 Minimum Essential Requirements feature allows you to make secure calls in a modem over IP network. The feature uses a dialup modem for large installed bases of modems and telephony devices operating on a traditional public switched telephone network (PSTN). For more information to configure V.150, see the "Cisco V.150 Minimum Essential Requirements (MER)" chapter in the Security Guide for Cisco Unified Communications Manager. V.150 Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs 824 QoS Management Configure AS-SIP Features