Responding to postings by Colm MacCarthaigh and Marshall Eubanks: 1. There is practically no live television (at least in the United States). After the Janet Jackson episode, networks are inserting a 5-second (or perhaps it is a 10-second, I don't recall) pause, in order to stop anything untoward from showing up on the screen. Admittedly, there are live events (videoconferencing, or sports events that some people get a thrill out of watching in real-time), but that is a small fraction of total traffic. 2. Business models (such as advertising-financed TV) are certainly slow to change, as both businesses and consumers do not alter their habits on Internet time. But neither business models nor consumer habits need to change when you move from streaming to file downloads. As long as the transmission does not have to be absolutely real-time (as it does with videoconferencing), you gain a lot. Say you have a 3 Mbps download link, and the transmission speed of your video is 1 Mbps, start shooting it down at 3 Mbps (possibly allowing the customer to start watching it right away), and after 5 seconds you will have the first 15 seconds in the buffer on the customer's device. Even if that person has been watching from the beginning, you now have a 10-second grace period when you can tolerate a complete network outage without disturbing your customer. Just think of how much simpler that makes the network! And if you do worry about long videos not being viewed to the end, shoot them down to the customers in 10-second increments. This solves concerns about advertising and everything else. And of course you can encrypt the files, and do whatever else you want. Andrew P.S. I have been puzzled by the fixation on streaming for over a decade. A couple of years ago I wrote about it in "Telecom dogmas and spectrum allocations," http://www.dtc.umn.edu/~odlyzko/doc/telecom.dogmas.spectrum.pdf At my networking lectures, I often do a poll, asking how many people in the audience see any advantage (for consumer, or service providers, very vague requirement) in faster-than-real-time download of video. The response rate has ranged from 0 to 20%, with the 20% rate at two networking seminars at Stanford and CMU, full of networking graduate students, professors, VCs, and the like. There is a (small) fraction of people who see buffering and file downloads as the obvious thing, and others mostly have never even imagined such a thing. What's strangest is that the two camps seem to coexist without ever trying to debate the issue. -------------------------------------------------------------------------- On Sat, Jan 06, 2007 at 09:09:19AM -0600, Andrew Odlyzko wrote:

2. The question I don't understand is, why stream?

There are other good reasons, but fundamentally; because of live telivision.

In these days, when a terabyte disk for consumer PCs is about to be introduced, why bother with streaming? It is so much simpler to download (at faster than real-time rates, if possible), and play it back.

That might be worse for download operators, because people may download an hour of video, and only watch 5 minutes :/ -- Colm MacCárthaigh Public Key: colm+pgp@stdlib.net -------------------------------------------------------------------------- Dear Andrew; On Jan 6, 2007, at 10:09 AM, Andrew Odlyzko wrote:

A remark and a question:

<snip>

2. The question I don't understand is, why stream? In these days, when a terabyte disk for consumer PCs is about to be introduced, why bother with streaming? It is so much simpler to download (at faster than real- time rates, if possible), and play it back.

I can answer that very simply for myself : We are now making a profit with streaming from advertising. To answer what I suspect is your deeper question : Broadcast is a push model, and will not go away. If fact, I think that the Internet will revitalize the "long tail" in video content, and broadcast will be a crucial part of that. It, after all, has been making more for over a century now. Download appears to be very similar, but is really not the same business model at all IMHO. Doesn't mean it's bad or worse, it may even be better, but it's different. And as long as you can make a profit from broadcasting / streaming...

Andrew

Regards Marshall -------------------------------------------------------------------------- On Jan 6, 2007, at 10:19 AM, Colm MacCarthaigh wrote:

On Sat, Jan 06, 2007 at 09:09:19AM -0600, Andrew Odlyzko wrote:

...

2. The question I don't understand is, why stream?

There are other good reasons, but fundamentally; because of live telivision.

...

In these days, when a terabyte disk for consumer PCs is about to be introduced, why bother with streaming? It is so much simpler to download (at faster than real-time rates, if possible), and play it back.

That might be worse for download operators, because people may =20 download an hour of video, and only watch 5 minutes :/

Our logs show that, for every 100 people who start to watch a stream, =20= only 2 or 5 % watch over 30 minutes in one sitting, even for VOD where they presumably have =20 some interest in the movie up front, and more more than 9% will watch all of VOD movie, even over multiple =20 viewings. This is also very consistent with time, but I don't have any pretty plots handy. (Our cumulative =20 audience in 2006 was 2.74 million people, I have lots of statistics.) So, from that standpoint, making a video file available for download =20 is wasting order of 90% of the bandwidth used to download it. Regards Marshall

--=20 Colm MacC=E1rthaigh Public Key: colm=20 +pgp@stdlib.net