Session Description Protocol (SDP) objects represent a multimedia session described by the SDP. An SDP object can be received from either Session Initiation Protocol (SIP Invite, Response, or Ack) or Media Gateway Control Protocol (MGCP).
Provides the connection information for the session.
String
Type of network. For example, IN = Internet.
String
Type of address specified by the address property that follows. For example, IP4 or IP6.
String
Connection address.
Number
Time to live value that, along with the address property, defines the scope multicast packets in this connection are sent with.
Number
Number of addresses. This property can be used for applications requiring multiple multicast groups. If the number of addresses is not given, it is assumed to be 1.
Describes the media that is offered for the session.
String
Type of media to be offered in the session.
Number
First port to be used for the session.
Number
Total number of ports to be used for the session.
String
Transport protocol used for the session.
Note
The ports used for the session depend on the transport protocol.
String
One or more media formats to be used for the session.
Specifies the originator information for the session.
String
User name on the originating host.
String
Numeric string such that the tuple of username, session id, network type, address type, and address form a globally unique identifier for the session.
String
Version number for this announcement.
String
Type of network. For example, IN = Internet.
String
Type of address specified by the address property that follows. For example, IP4 or IP6.
String
Globally unique address of the machine that the session was created from.
Array of strings, each corresponding to an a=line that is associated with this media description.
Number
Type of payload for the session.
String
Name of the media encoding encapsulated in the RTP stream.
Number
Clock rate or frequency (Hz) of the media stream.
Number
Number of audio channels. This can be omitted if only one channel is provided.
Note
No encoding parameters are currently specified for video streams.
Simple “string” parameter that specifies the session subject information. For example, phone call.
Indicates the time during which the session will be active.
String
Time the session starts.
String
Time the session ends.
Note
These values are the decimal representation of Network Time Protocol (NTP) time values in seconds.
Simple “number” parameter that specifies the SDP version number. For example, 0.