Comcast's bandwidth squeeze

<p>ByNATHAN HALVERSON</p><p>THE PRESS DEMOCRAT</p><p>Is Comcast running out of bandwidth?</p><p>The answer depends on who you ask.</p><p>Stan Schatt, who covers the broadband industry for ABI Research, said cable networks are reaching capacity. As people begin downloading more videos, especially high-definition shows online, the traffic problems will get worse, he said.</p><p>“The dirty little secret in the industry is these cable guys are going to run out of bandwidth,” Schatt said. “Comcast’s clampdown on usage is kind of a warning sign, a harbinger that bandwidth is becoming more and more of an issue.”</p><p>But Comcast disagrees. “Unfortunately, he doesn’t understand how we are managing our network,” said Andrew Johnson, vice president of communication for Comcast.</p><p>The cable TV and Internet company has plenty of bandwidth capacity, especially in the Bay Area where it has spent $680million in the past five years upgrading its networks, Johnson said. Part of that upgrade included a new network in Santa Rosa, which pushed fiber lines even deeper into neighborhoods and increased bandwidth.</p><p>Comcast’s current infrastructure meets its capacity needs for a “good number of years,” Johnson said. But he declined to provide a more specific number, saying such information would tip off AT&T, its prime competitor in the Bay Area.</p><p>AT&T and Comcast are locked in a high-stakes battle for Internet subscribers in the Bay Area and other markets. Nationwide, the number of people who subscribe to DSL versus cable is pretty evenly split, according to ABI Research. About 31percent of households have cable Internet access, while 26percent have DSL.</p><p>The Internet congestion Comcast is worried about happens within the last few miles to a subscriber’s home, and it highlights a key difference between DSL and cable Internet technologies.</p><p>With cable, a person’s Internet files leave the house and almost instantly join up with their neighbors’ Internet data on the black coaxial cable hanging along utility poles or buried underground. A neighborhood’s combined data races along the coaxial cable to a nearby utility box, where Comcast transfers everyone’s files onto high-speed fiber-optic cables. Fiber-optic cables have enormous bandwidth and connect to other fiber-optic networks that crisscross the globe, forming the backbone of the Internet.</p><p>But because a neighborhood shares the same coaxial cable that runs to the utility box, a few heavy users can clog the connection and slow things down for others. </p><p>With DSL, customers don’t share a connection to the fiber-optic line. A copper telephone wire goes directly from a house to a nearby utility box, where the data is transferred onto fiber. Each house in the neighborhood has its own copper wire, and therefore another person’s Internet usage has no impact. But telephone lines can not carry as much data as cable TV lines.</p><p>Coaxial cables can carry huge amounts of data, including hundreds of TV channels, phone service and broadband Internet.</p><p>The common perception is that cable Internet is faster, and that is pretty much true. Comcast subscribers in Santa Rosa regularly can obtain download rates of 15 megabytes per second to 20Mbps — although it dips significantly when there is congestion. AT&T’s fastest DSL speed is 6Mbps.</p><p>New DSL technology is allowing Santa Rosa-based Internet provider Sonic.net to roll out residential speeds of 18Mbps, and it has no cap.</p><p>Yet cable speeds are expected to increase next year. Comcast will start delivering speeds of 50Mbps to 150Mbps in California next year, Johnson said. At that speed, a Comcast customer could download 250 gigabytes in about three hours and 45 minutes. Of course, not everyone in the neighborhood could run at that speed without creating congestion.</p><p>The question of just how much congestion will result is the point of disagreement between analysts and Comcast, and will ultimately determine if Comcast’s network is robust enough.</p><p>You can reach Staff Writer Nathan Halverson at 521-5494 or nathan.halverson@pressdemocrat.com.</p>