Specifications

4-3
Cisco Unified IP Phone Services Application Development Notes
OL-22505-01
Chapter 4 Component APIs
RTP Streaming API
Note Support for the Application Management API requires an updated XML Parser (see “Updated XML
Parser and Schema Enforcement” section on page B-1 for details).
RTP Streaming API
This XML-based RTP Streaming API allows applications to initiate and observe RTP audio streams. It
extends capabilities beyond the legacy RTP streaming URIs by providing support for stream start/stop
event listeners and the ability to specify other extended stream attributes, such as codec type.
Note Support for the RTP Streaming API requires an updated XML Parser (see “Updated XML Parser and
Schema Enforcement” section on page B-1 for details).
The event handlers typically use the standard Notification framework (see “Notify” section on
page 5-18), but they can also invoke most other URIs, with the exception of HTTP URLs.
Interaction Rules with Legacy RTP URI Streams
The RTP Streaming API allows a full-duplex stream (mode=sendReceive) to be setup as a single stream
request which simplifies the usage of the API. However, in some cases, this creates some interoperability
issues with the legacy RTP URIs because the legacy RTP URIs send and receive streams separately. The
interaction rules between legacy RTP URI streams and the new RTP Streaming API are as follows:
• If an RTP Stop URI is invoked, and an RTP Streaming API stream is currently streaming in that same
direction, then the entire RTP Streaming API stream is stopped.
For example, if a full-duplex stream is setup through the RTP Streaming API (mode=sendReceive)
and then an RTPTx:Stop URI is invoked, the stream will be stopped in both the send and receive
directions (and the onStopped event handler will be called, if present).
• If the stopMedia request (from the RTP Streaming API) does not specify a stream ID, then the
request will stop all services RTP streams, in any direction (send or receive) and of any type
(multicast and unicast). This allows applications using the RTP Streaming API to stop media streams
which may have been started by the legacy RTP URIs or by other applications for which a stream
ID is not known.
RTP Streaming Schema
Note The port number parameter of the startMedia request is optional and if it is not specified, the phone
selects an available port and returns it in the
startMediaResponse object. The port parameter, if
specified, must be an even number in the range of 20480-32768.
<?xml version="1.0" encoding="UTF-8"?>
<!-- edited with XML Spy v4.4 U (http://www.xmlspy.com) by Cisco Systems, Inc. (Cisco
Systems, Inc.) -->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified"
attributeFormDefault="unqualified">
<xs:element name="startMedia">