Comment on Itunes 7.0 by Rian

Wed, 11 Oct 2006 11:51:01 -0700

Gigabit ethernet is only common in technology companies and at the home of technology enthusiasts. Your average corporation doesn’t have it because they don’t need it: it is an unnecessary expense.

I’ll stick with my 100Mbit example. About the max transfer rate over an unused 100Mbit line is about 12MB/sec. So assuming you have 500MB of album art, that’s going to be almost 42 seconds to load that. In the meantime, the other person’s machine is going to be grinding. God forbid you’ve only got 256MB on a machine with a bunch of background processes running. This is common on the average computer user’s machine both at home and in corporate environments. Can you say paging?

Of course that 12MB/sec assumes that serving album art is straight file serving. It’s not. Album art is embedded directly into the ID3v2 tag of the mp3. id3v2 tags are stored at the beginning of the mp3 before the music data. Straight file serving is cheap in terms of processing (and speed) than parsing 6000 mp3s and pulling metadata from each one. Add even 0.01sec of a second for each mp3 (generous, given the average user’s mess of an OS installation) and you’re going to end up with 60 seconds added to that original 42 seconds.

102 seconds to load album art. That’s not very user friendly, now is it?

In short, Apple would make more enemies than friends by including such a feature.

If you’d like to compare bandwidth usage for an average movie clip, we can do that too. Streaming individual movies is much friendlier than blasting 500-600MB over a network connection as fast as one can. Spread 500MB (which is about how much an iTunes Store television episode is) over 40 minutes?

Yeah you get the idea.