Part of the Cisco IP Voice Streaming Application
Streams spoken messages and various call progress tones. A set of predefined tones and announcement.
Receiving devices such as IP phones or gateway must be capable of SCCP to utilize this feature
<note important>Annunciator only work with SCCP. Not SIP, MGCP or H.323 so this pretty much rule out all the voice gateways and SIP phones</note>
Support G.711, G.729 and wideband codecs
The following feature require an annunciator. To explain why.
Cisco Multilevel Precedence Preemption (call failure)
Integration via a SIP trunk (call progress and DTMF tones)
Cisco IOS gateways and intercluster trunks (ringback)
System messages (call failure)
Conferencing (Barge tone)