Heads turned when Netflix (Nasdaq: NFLX) streams consumed one-fifth of the country's downstream traffic last fall. Now, the company's outgrown even that gargantuan number.

Sandvine -- the same residential broadband networking specialist that issued last year's report -- now grants Netflix an even bigger chunk of the nation's Internet traffic. The couch-potato fave most recently accounted for 29.7% of all downstream bandwidth during peak hours.

To put this into perspective, that's nearly three times the data being served through Google's (Nasdaq: GOOG) YouTube during the same period.

Keep in mind that we're talking about raw data here. Netflix media files are chunky, optimized to look killer on your high-def flat screen. YouTube can get by with much smaller files. Still, that doesn't make Netflix's reach any less enormous.

If it wasn't obvious before, now we know why content delivery networks Akamai (Nasdaq: AKAM), Limelight Networks (Nasdaq: LLNW), and Level 3 (Nasdaq: LVLT) have been brokering cutthroat deals to get a piece of Netflix's streaming action.

Netflix's digital stronghold also explains why studios aren't hesitating to cut content licensing deals with CEO Reed Hastings, even if they fear Netflix as a competitor. It's also no surprise to see Netflix talking down capped bandwidth plans, and becoming a vocal player in the net neutrality battle. Ensuring that its customers have unfettered access to plentiful bandwidth just makes good business sense for the ever-growing video giant.

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