Real Data Transport is a proprietary

Proprietary protocol

In telecommunications, a proprietary protocol is a communications protocol owned by a single organization or individual.-Enforcement:Proprietors may enforce restrictions through patents and by keeping the protocol specification a trade secret...

 transport protocol for the actual audio/video data, developed by RealNetworks

RealNetworks

RealNetworks, Inc. is a provider of Internet media delivery software and services based in Downtown Seattle, Washington, United States. The company is the creator of RealAudio, a compressed audio format; RealVideo, a compressed video format; RealPlayer, a media player; RealDownloader, a download...

 in the 1990s.

Commonly used in companion with a control protocol for streaming media

Streaming media

Streaming media is multimedia that is constantly received by and presented to an end-user while being delivered by a streaming provider.The term "presented" is used in this article in a general sense that includes audio or video playback. The name refers to the delivery method of the medium rather...

 like the IETF's based RTSP

Real Time Streaming Protocol

The Real Time Streaming Protocol is a network control protocol designed for use in entertainment and communications systems to control streaming media servers. The protocol is used for establishing and controlling media sessions between end points...

 protocol.

An alternative IETF's based transport protocol is RTP

Real-time Transport Protocol

The Real-time Transport Protocol defines a standardized packet format for delivering audio and video over IP networks. RTP is used extensively in communication and entertainment systems that involve streaming media, such as telephony, video teleconference applications, television services and...

, fully implemented, like RTSP

Real Time Streaming Protocol

The Real Time Streaming Protocol is a network control protocol designed for use in entertainment and communications systems to control streaming media servers. The protocol is used for establishing and controlling media sessions between end points...

, in RealNetworks

RealNetworks

RealNetworks, Inc. is a provider of Internet media delivery software and services based in Downtown Seattle, Washington, United States. The company is the creator of RealAudio, a compressed audio format; RealVideo, a compressed video format; RealPlayer, a media player; RealDownloader, a download...

 players.

RDT is now included as part of the Helix Community project.

External links

• Helix Community RDT implementation, C++ source code repository.
• RDT v2 protocol specs from Helix Community
• RDT v3 protocol specs from Helix Community