Streaming vs. progressive download

Jul 15, 2008 at 8:59 AM
We're considering if we should offer our podcasts (video's) via streaming media or via progressive download. Can anyone tell me which is a good practice performance-wise? When should one consider using progressive download and when whould streaming be an better option? Do you have any figures on that? Or even better, are there already (I know it’s early ;-)) some reference cases on this?
Coordinator
Jul 15, 2008 at 7:40 PM
Heyjules,

I'm not sure what we have for you at this time, but I will check with our team and see if there's any info on what you're asking.

Chevas
Coordinator
Jul 17, 2008 at 8:05 AM
Heyjules,

We were able to get some information for you on this.  In general, streaming video solutions are more costly and do not scale as easily as progressive downloads.   Using the progressive download method allows users to fully seek and navigate at any time without having to download the entire file.  Also, progressive download uses "bandwidth throttling" which by specifying the exact bit rate at which files should be delivered, only the necessary portion of video required to view it will be delivered, thus saving bandwidth.  In addition, it's worthwhile pointing out that the majority of sites serving internet videos deliver videos using the progressive download method.



heyjules wrote:
We're considering if we should offer our podcasts (video's) via streaming media or via progressive download. Can anyone tell me which is a good practice performance-wise? When should one consider using progressive download and when whould streaming be an better option? Do you have any figures on that? Or even better, are there already (I know it’s early ;-)) some reference cases on this?


Jul 21, 2008 at 8:48 AM

Chevas,

Thank you for your reply. I'm not sure if I understand you correct: In my understanding streaming-technology only sends information over the line that is actually watched, and when using progressive download tries to download the video asap so that the user can watch and easily 'browse' to the video (like YouTube works). When you use this example: a user only watches the first 10% (time-wise) of a video, only 10% of the video is sent over the line using streaming technology. But when using progressive download, a lot more of this video has already been downloaded (and thus more bandwidth has been consumed).

So, taking this in consideration, what would be the performance considerations? What do you mean with 'do not scale as easily as progressive download'? Is this based on the scalability of Media Servers or on the bandwidth?


chevas wrote:
Heyjules,

We were able to get some information for you on this.  In general, streaming video solutions are more costly and do not scale as easily as progressive downloads.   Using the progressive download method allows users to fully seek and navigate at any time without having to download the entire file.  Also, progressive download uses "bandwidth throttling" which by specifying the exact bit rate at which files should be delivered, only the necessary portion of video required to view it will be delivered, thus saving bandwidth.  In addition, it's worthwhile pointing out that the majority of sites serving internet videos deliver videos using the progressive download method.
Coordinator
Jul 25, 2008 at 2:17 PM
I think what Chevas meant was that there has been several enhancements made lately to progressive download technology like variable bit rate (the bit rate changes according to the bandwidth available during the playback) or the download shifting allowing only the next 5 minutes to be downloaded in ordr to not waste bandwidth if the user cancels his payback. These are all available in IIS / Windows Media / Windows Server 2008 and are providing significant business value and ROI. Heyjules, you're right bandwidth is also optimized with streaming, just differently with multicast options etc.
I hope that helps.