QuickTime Streaming Server (QTSS) is Apple's commercial streaming server delivered as part of Mac OS X Server. QTSS provides users with enhanced administration and media management tools as a result of the tight integration with Mac OS X Server; these tools are not available as part of the open source projectQuickTime Streaming Server delivers hinted QuickTime (.mov), hinted MPEG-4 (.mp4), and hinted 3GPP (.3gp) files in real time over the Internet and mobile networks via the Real-time Transport Protocol/Real-Time Streaming Protocol (RTP/RTSP). It can also deliver MP3 files via Icecast-compatible protocols. It delivers both video on demand (VoD) and, when combined with broadcasting software, live streams. It is perfect for serving live events over the web, when partnered with broadcaster software, or for creating a 24x7 video or radio station with the included Playlist Broadcaster, or delivering long-form media. It is also perfect for those concerned with customers downloading files locally: real time streaming means the data is “consumed” as it is delivered, leaving no file to play back locally.

QuickTime Streaming Server, while designed for Mac OS X Server, is also available via the Darwin open source project, which offers a high level of customizability to just about any network.

While sharing the same code base as QuickTime Streaming Server, Darwin Streaming Server is an open source project intended for developers who need to stream QuickTime and MPEG-4 media on alternative platforms such as Windows, Linux, and Solaris, or those developers who need to extend and/or modify the existing streaming server code to fit their needs. Darwin Streaming Server is only supported by the open source community and is not eligible for technical support from Apple. Apple hosts a number of email discussion lists for Darwin Streaming Server users and developers to share ideas and discuss deployment scenarios.

Both DSS and QTSS are built on a core server that provides state of the art quality of service features with Skip protection and Instant-On, and support for the latest digital media standards, MPEG-4 and 3GPP.