Hitachi has unveiled a prototype streaming storage appliance at CeBIT optimised for video-on-demand (VoD) services.

The increase in HD content and the huge adoption of broadband around the world has allowed viewers to watch more and more of this content via streaming over the internet.

VoD providers have had to add more servers and storage to compensate for the increases in performance that HD requires.

In response to this need, Hitachi researchers developed a streaming-optimised storage appliance equipped with video stream delivery functions.

By embedding the Hitachi streaming-optimised kernel and streaming engine software video can be streamed directly from the storage appliance without passing through an external streaming server.

The system executes video stream delivery through its streaming engine software, which is completely compatible with Windows Media 9 Series unicast streaming protocols.

"Hitachi's new streaming technology possesses performance and scalability advantages that will appeal to many service providers," said Chris Knowlton, lead programme manager for Windows Media Services at Microsoft.

"Microsoft and Hitachi will continue our close collaboration around Windows Media Technologies to provide our customers with the most scalable and cost effective streaming solutions."

In an interview with vnunet.com, Hitachi researcher Hiroshi Mine demonstrated a simulated environment from a standard Windows server compared with one running Hitachi's Tactix operating system.

The video stream from the Windows server started to stutter and lag when the user count reached around 400, but the Tactix server continued to run smoothly even when feeding the stream to 2,000 users.

Mine said that the Tactix operating system was developed from scratch by Hitachi and focuses primarily on the I/O operations required for smooth media streaming, namely disk reads and network sends.

The kernel uses a range of options to help keep streaming smooth no matter what the load.

These include a timing control mechanism that eliminates memory copies between user and kernel modes, CPU allocation which ensures that each stream receives prioritised CPU time and a traffic-shaped delivery system to help prevent packet loss.