You can watch a live stream of Apple’s fall event tomorrow, the company has announced – but only if you’re using an Apple device.

Apple will broadcast the event using its internally-developed HTTP Live Streaming Protocol, which requires either a Mac running Safari on Mac OS X version 10.6, an iPhone or iPod touch running iOS 3.0 or higher or an iPad. It’s not because Apple only wants its fans watching, however.

“QuickTime X, a major leap forward that advances modern media and Internet standards”

The HTTP live streaming protocol is a feature of the latest version of Apple’s multimedia player and framework, QuickTime X. The new protocol lets users stream audio and video over HTTP. This makes things easier for broadcasters, who can use a standard Web server instead of a special media server to stream in almost-real time. Apple claims the protocol also avoids common problems with other streaming protocols.

The protocol also dynamically adjusts playback quality based on the speed of the connection, making it ideal for mobile devices like the iPhone, iPad and iPod touch.

QuickTime X is included in the latest version of Mac OS X Snow Leopard, but it’s not been ported to Windows yet. The most recent version of QuickTime available for Windows users is the second-newest version, 7.6, released in January of last year.

Apple praised its new protocol in June 2009 for being “based on open standards” which should make the technology more accessible. Apple even submitted the protocol to the Internet Engineering Task Force (IETF) for consideration as a universal standard.

But more than a year later, the standard is effectively proprietary. It’s been criticized for being more complicated to implement than advertised. And Microsoft has not said anything about when or whether Windows will support QuickTime X – meaning the vast majority of Web users are not yet on the receiving end.