Adding Speed, With Ease


Technology executives at cable firms agree that boosting speeds to meet the demands of the residential market — even the ravenous bandwidth appetites of voracious videogamers and music downloaders — has not yet posed any problems.

“We’ve got enough experience with broadband to understand traffic engineering issues and to scale networks appropriately,” says Ralph Brown, chief technology officer of Cable Television Laboratories Inc. “The capability is there,” he adds, noting that [Data Over Cable Service Inteface Specification] DOCSIS 2.0 equipment — cable-modem termination system equipment at the headend and home modems — can handle “up to 38 Mbps on a burst rate.”

“There isn’t any equipment they need to add or buy when [cable operators] move from 1.5 Mbps to 3 to 9 to 15,” Brown says. Although he acknowledges that “there is a lot of DOCSIS 1.0 and 1.1 hardware still in the field,” some of which “cannot handle the highest speeds.”

“Adding a line card to an existing CMTS” or upgrading equipment at the node is all it takes, Brown says.

At Comcast Corp., increased demand sometimes requires adding nodes within the local networks, but not necessarily installing more headend hardware, according to a spokeswoman there.

A relatively simple software download to existing modems can upgrade capability, as Comcast is doing in its recently unveiled migration from a standard offer of 4 Mbps to 6 Mbps.

Charter has a five-step process for its speed upgrades, starting with modification to its provisioning systems and creation of new billing system codes for the faster service. Like Comcast and other MSOs, Charter updates its modem configuration to recognize the higher-speed tiers.

Charter technicians then measure the CMTS for capacity to support bandwidth and utilization growth and to make necessary adjustments (e.g., combining).

Finally, they measure the metro backbone and “Internet Drains” for capacity to support the expanded bandwidth growth.

Cablevision Systems Corp. has been exploring the upper speed limits, including a recently completed trial of a business-oriented 100 Mbps data service in Oyster Bay, N.Y., in partnership with Narad Networks Inc. More typically, Cablevision runs 10 Mbps throughout its New York metro area systems, although officials there acknowledge that its Optimum Online customers have an “average speed” of 5 Mbps, with an unusually fast 1 Mbps upstream capability.

Insight Communications Co. vice president of broadband services Bryan Smith says his MSO’s largest challenge related to speed is simply keeping up with demand. Insight is adding a 6 Mbps service by autumn at $79.95 per month.

But even before that kicks in, Insight’s high-speed subscriber base is up 40% this year, Smith says. “We’re adding more CMTSs,” he notes. Once that equipment is in place, upgrades are easy. All his engineers do is “dial it in.”