Cisco SPA525G Administration Guide - Page 119

Configuring Security, Quality, and Network Features Setting Security Features 6 SRTP and Securing Calls Secure Real-Time Transport Protocol (SRTP) is a secure protocol for transporting real-time data over networks. SPA9X2 phones use SRTP to securely send and receive real-time voice traffic from other phones and gateways. Security Description (RFC 4568) is supported. SRTP provides media encryption to ensure that media streams between devices are secure and that only the intended devices receive and read the data. When a call is secure, the voice conversation is encrypted so that others cannot eavesdrop on the conversation. To enable this feature the SPA9X2 phone must have a mini-certificate installed. The supplementary service Secure All Calls (*16)-Defaults to prefer to use encrypted media (voice codecs). Audio packets in both directions of outbound calls are encrypted using SRTP. To use Secure Call on an extension, you must configure Mini Certificate and SRTP Private Key for that extension. These parameters appear on the Ext tabs. Secure Call Service activates secure encryption of RTP streams between the two endpoints. You can disable this if the other endpoint (or gateway) does not support this proprietary method. To enable the secure call service: STEP 1 Log in to the web administration interface. STEP 2 Click Admin Login and advanced. STEP 3 Click the Phone tab. STEP 4 In the Supplementary Services section, under Secure Call Serv, choose yes. STEP 5 Click Submit All Changes. NOTE This feature can also be configured from the User tab, under Supplementary Services. Users can enter *18 to Secure Next Call-Uses encrypted media for the next outbound call (on this call appearance only). This star code is redundant if all outbound calls are secure by default. Cisco SPA and Wireless IP Phone Administration Guide 117