Cisco SPA2102 Administration Guide - Page 33

Introducing Cisco Small Business Analog Telephone Adapters ATA Software Features 1 Feature SIP Over TLS Media Loopback Description SPA2102, SPA3102, and SPA8800 devices allow the use of SIP over Transport Layer Security (TLS). SIP over TLS is designed to eliminate the possibility of malicious activity by encrypting the SIP messages of the service provider and the end user. SIP over TLS relies on the widelydeployed and standardized TLS protocol. SIP Over TLS encrypts only the signaling messages and not the media. A separate secure protocol such as Secure Real-Time Transport Protocol (SRTP) can be used to encrypt voice packets. SIP over TLS is configured in the SIP Transport parameter configured in the Line tab(s). See "ATA Voice Field Reference," on page 115. SPA2102, SPA3102, and PAP2T devices allow service providers to use media loopback to quantitatively and qualitatively measure the voice quality experienced by the end user. One device acts as the audio transmitter and receiver while the other device acts as the audio mirror. The audio mirror transmits the audio packets that it receives back to the transmitter/receiver instead of transmitting the data sampled on its local microphone (IP phone) or attached analog telephone (ATA-type device). Media loopback is configured in the User tab. See "ATA Voice Field Reference," on page 115. Cisco Small Business ATA Administration Guide 33