The
Real-time Transport Protocol (RTP) specifies a general-purpose data format and
network protocol for transmitting digital media streams on
Internet Protocol
The Internet Protocol (IP) is the network layer communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet.
IP ...
(IP) networks. The details of media encoding, such as signal sampling rate, frame size and timing, are specified in an RTP payload format. The format parameters of the RTP payload are typically communicated between transmission endpoints with the
Session Description Protocol (SDP), but other protocols, such as the
Extensible Messaging and Presence Protocol (XMPP) may be used.
Payload types and formats
The technical parameters of payload formats for audio and video streams are standardised.
The standard also describes the process of registering new payload types with IANA.
*
*
*
*
Text messaging payload types
Payload formats and types for text messaging are defined in the following specifications:
*
*
MIDI payload types
Payload formats and types for
MIDI
Musical Instrument Digital Interface (; MIDI) is an American-Japanese technical standard that describes a communication protocol, digital interface, and electrical connectors that connect a wide variety of electronic musical instruments, ...
are defined in the following specifications:
*
*
Audio and video payload types
Payload formats and types for audio and video are defined in the following specifications:
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
Payload identifiers 96–127 are used for payloads defined dynamically during a session. It is recommended to dynamically assign port numbers, although port numbers 5004 and 5005 have been registered for use of the profile when a dynamically assigned port is not required.
Applications should always support PCMU (payload type 0). Previously, DVI4 (payload type 5) was also recommended, but this was removed in 2013.
See also
*
Session Initiation Protocol
*
H.323
*
Comparison of audio coding formats
References
{{reflist
External links
IANA assignments of Real-Time Transport Protocol (RTP) Parameters
VoIP protocols