It's been three weeks since Netflix (Nasdaq: NFLX) CEO Reed Hastings took Comcast (Nasdaq: CMCSA) (Nasdaq: CMCSK) to task on his Facebook feed.

"Comcast no longer following net neutrality principles," he wrote at the time. "Comcast should apply caps equally, or not at all."

His comment was based on his own experience as a Comcast subscriber. He was using his Xbox to stream Netflix, Hulu, Time Warner's (NYSE: TWX) HBO GO, and Comcast's own Xfinity, and lamented how Comcast as an Internet provider doesn't count Xfinity usage against the data cap. Why should Xfinity as a stream be any different than other video apps? The move encourages users to rely more on Xfinity and avoid third-party services.

Well, it may get even murkier than that.

Streaming Media Blog's Dan Rayburn now claims to have proof that Comcast is prioritizing Internet traffic for Xfinity to the detriment of Hastings' company and every other third-party streaming provider.

"Based on details I have gotten from those who have looked at how packets are marked on their home broadband connections provided by Comcast, packets are in fact being marked with Quality of Service tags," he writes, pointing out how media files from Xfinity are being marked as high priority while streaming media from MLB, Hulu, Netflix, and others are being tagged as having low priority. Even though the non-Xfinity traffic is originating from the servers hosted by Level 3 (Nasdaq: LVLT) and Akamai (Nasdaq: AKAM), Rayburn claims that Comcast is the one putting the tags on the streams.

This is a smoking gun, though it's not necessarily loaded. The intent is there to treat non-Xfinity streams as second-class netizens, but until we get verified reports that Comcast is deliberately slowing down third-party streams during peak usage periods we can't tag the country's largest cable provider as being officially evil.

Right now it's just a matter of leaving Comcast with some serious explaining to do.

If the answers don't add up, then we have a smoking pitchfork.

Stream on
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