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Jim Huggins
March 19th, 2009
01:02 pm
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An interesting exercise in network management
For those of you who aren't naturally interested in sports ... the NCAA Men's Basketball Tournament begins today.  And so, while lots of people (like me) are stuck at work, CBS is streaming every game on the Internet.  In the past, this sort of thing has tended to be unpredictable in its reliability, as nobody's quite sure what the demand will be on the servers, much less everyone's local network, as all the sports geeks tie up the 'net watching games.  

(Ah, I can remember the old days of the 'net, when the entire network was brought to screeching halt when the website for Showgirls went live, and everyone was trying to look at half-naked pictures of Elizabeth Berkley.  (Or, at least, that's what I was told.  I certainly wouldn't have tried to access that site.  [cough])

So, I fired up the viewer today out of curiosity, and discovered an incredibly interesting feature.  On the control panel is a slider which allows the viewer to pick the streaming bit rate quality ... along with a recommendation that "if your viewing is interrupted by frequent buffering, consider reducing the streaming rate".

This is cool, particularly from an academic perspective.  In essence, it's taking the problem of network management and distributing much of it down to the client level.  People can figure out for themselves what the best bit rate is simply by watching the performance they're getting, and adjusting accordingly.  No need for centralized monitoring of the system; the system essentially monitors itself.

There's something profound going on here.  I like it.

Current Mood: contemplativecontemplative
Current Music: Butler vs. LSU on CBS

(3 comments | Leave a comment)

[User Picture]
Date:March 19th, 2009 06:34 pm (UTC)
Once sites introduced the notion of "High Def" content in addition to the normal bitrate, many sites tried to auto-detect which version works the best for people. However, their methods were often flawed (why, I don't know), which wound up with people getting the wrong settings for themselves.

Now most default to the highest quality and offer the ability to "turn off" HD.

While it's certainly useful for them to offer that, and in fact to suggest it when playback becomes very sluggish, I think that both clients and providers (the entire Internet, in fact) would benefit greatly from better algorithms/methods to determine the best bitrate. A user's stated connection method (56k/dsl/cable) isn't good because service often varies tremendously from the touted speeds. If narrowed down so only 1% of users had to switch, it would save the providers a lot of money both by delivering only the content needed, and then also because anyone viewing time-shift materials wouldn't have to restart the video (as many players seem to require when switching to/from HD).

So, while it's good that they're doing this, I think it can (and should) be done better.
[User Picture]
Date:March 19th, 2009 06:43 pm (UTC)
A user's stated connection method (56k/dsl/cable) isn't good because service often varies tremendously from the touted speeds.

And the reason that varies tremendously is because it's not just the bandwidth that's the issue, but the load on that bandwidth ... and, more importantly, the load on the bandwidth upstream. I might have a 100Mbps line into my office machine here, but if everyone on campus is watching the game right now, the poor router serving all of us is gonna get crushed.

In short, you're only as good as your weakest link.

To do a better job, you'd need to get real-time information back to the server regarding round-trip delivery times and overall load. Which means that companies would have to be willing to broadcast their real-time network capabilities to the world ... and I could see why that some might find that undesirable.
(Besides the fact that you're now sending a bunch of information back upstream, which serves to congest the network even further.)

Like I said, this solution impresses me; it essentially allows everyone to vote on what the throughput of the network should be. (Kinda like the Prisoner's Dilemma, but without the threat of prison. :))
[User Picture]
Date:March 19th, 2009 11:07 pm (UTC)
Unfortunatly at work the default is to block a website and only allow access through a website unblocking form, which means only work related web surfing :(

Michigan is about to start, wouldn't it be great to have Michigan v MSU in the Championship game in Detroit! Its a bit of a long shot though, but its possible :).

Here is my bracket:

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