Main

February 27, 2008

AT&T: Sample Cable Modem Speeds Average 400 kbps


AT&T Group President John Stankey said today that a 150-home test of cable modem service in one market found that cable modem download throughput rates averaged 300 kbps to 400 kbps, far below the 6 to 8 mbps advertised by the cable companies. Speaking at Merrill Lynch's Communications Forum (webcast here), Stankey presented the results of the test, which took place in one unnamed market.

attmsotest1.jpg

In that market, AT&T recruited over 150 different residential homes, which then purchased cable modem services. AT&T put probes on the network to track for several months the cable operator's (or maybe multiple operators') high-speed Internet performance.

Even though peak speeds averaged around 3 Mbps during periods of low congestion, still far below the 6 to 8 Mbps speeds, average speeds hovered around 300 kbps to 400 kbps.

attmsotest2.jpg

Stankey's point in raising these test results is to argue that "it's not just good enough to talk about access speeds" at the local level. "The local access speed is not indicative of what the end-to-end performance is."

Rather, "the way you manage performance is by having a complete set of skills that you manage across the network," Stankey said. As it so happens, AT&T has a national fiber-based backbone that feeds its own DSL connections. "The IP backbone gives us tremendous capability to manage the service."

Stankey's test raises more questions than it answers. How is it possible that the advertised throughputs are so much dramatically higher than the average speeds delivered? Would AT&T's own DSL service produce the same kind of results? How does this square with conflicting information obtained from users themselves?

 

Cynthia Brumfield at 2:22 PM|Comments(3)

  

Comments

I have used DSL for a few years now with different rates of speeds from 1.5 meg to 6 meg and never could tell a fluxuation in speeds. Cable you see a dramatic slowdown when everyone gets off work and gets home and on the internet. that is the whole problem with cable.

Posted by: Jpotts at March 4, 2008 10:45 AM

I get over 6megs down and 1meg up on my comcast cable modem. I work for a phone company installing and troubleshooting dsl all day and honestly i have to say compared to cable, dsl sucks.

Posted by: Diamond at March 1, 2008 11:45 AM

I have been asking the same question about advertised vs realised download speeds for years. It is good to see someone else raise the issue.

Posted by: Wyatt Ditzler at February 28, 2008 3:23 PM

Post a comment




Remember Me?

(you may use HTML tags for style)

Verification (needed to reduce spam):