PreAnswer (Early Media)
The PreAnswer or Early Media feature is supported for Session Initiation Protocol (SIP)calls. Early Media is the ability of two user agents to communicate before a call is actually established. Support for early media is important both for interoperability with the Public Switched Telephone Network (PSTN) and billing purposes. Early Media is defined when media begins to flow before the call is officially connected. Media channels are set up prior to the call connection. These channels are used to provide the ring tone that the caller hears and are not generated by the caller’s endpoint or other queuing services, for example, hold music, roaming tone, local ringtone, announcement
| Parameter | Category | Description |
|---|---|---|
| name |
string required
|
The name class |
| desc | string |
description for class |
| streams | list |
list of stream object |
| Parameter | Category | Description |
|---|---|---|
| type |
enum required
|
tone: tone script follow ITU-T Recommendation E.180 media: filename (fullpath) of audio file speak: text to speak |
| stream | string |
stream data follow the media type |