TI Says Time to Rev Up Throughput Turbocharger

After more than two years in low idle, Texas Instruments Inc. says it's time for cable-modem vendors and cable operators to add a little throughput nitro to their high-speed products.

The Dallas-based provider of silicon, software and cable-modem reference designs has targeted 2003 as the year its TurboDOX modem accelerator firmware will finally hit the market in full gear, according to Dennis Rauschmayer, director of marketing and applications for the company's cable-modem products.

An upgrade for Data Over Cable Service Interface Specification modems that use TI silicon, TurboDOX promises to keep cable modems zipping at broadband speeds even during the Internet rush hour.

TurboDOX does this by tweaking the session rules under the Transport Control Protocol, which essentially governs how data is exchanged between two computers in a network. In a typical TCP exchange, the sending computer fires off data, and the receiving computer sends back an acknowledgement packet.

During peak Internet-congestion periods, though, the acknowledgement packets can be delayed, causing the sender computer to stall as it stubbornly waits for the tardy data.

TurboDOX uses acknowledgment filtering to handle the problem. When the program senses that a session is close to stalling, it adjusts the requirements so all the acknowledgment data is not required. That allows the sender to continue without waiting for as many waylaid packets.

TI claimed the strategy can improve performance during peak network-congestion periods by 20 times, with an improvement of three to 10 times during off-peak times.

"It keeps your broadband always broadband," Rauschmayer said.

Certification go-aheads

TurboDOX has been ready to go for more than a year. It hasn't reached consumers yet, because it needed to pass the test with modem makers.

Before they agreed to use the accelerator in their designs, modem makers had to be convinced that it would not interfere with basic DOCSIS functions, according to Rauschmayer. So TI put the design through the last Cable Television Laboratories Inc. certification wave, and the unit passed the DOCSIS 1.1 test in December.

That's the case with Toshiba America Information Systems Inc. In the past, TurboDOX has not been activated on Toshiba's DOCSIS cable modems, but that will now change, according to Christopher Boring, marketing communications manager for Toshiba's network products division.

"It's going to be in all of the new products and all of the new certifications that we are doing," Boring said. "We are really excited — we have been looking at it and talking about it since they first started it."

Toshiba also has included TurboDOX on its download site, so cable operators can pass it on to modems already in the field.

But whether cable operators pass TurboDOX on to their existing base of TI-driven modems remains to be seen, according to Michael Harris, president of analysis firm Kinetic Strategies Inc.

Such accelerator additions will likely be associated with tiered data services, which cable operators have only dabbled in so far, Harris noted.

"So to the extent that they have been rather stagnant in that area, I don't know that it's fair to expect that there would be a very big move for a TurboDOX service," he said. "That said, because there is no change required on the network, and no change required on the CMTS, the operator need not participate."

Harris noted the more interesting test concerns whether modem vendors such as Toshiba use TurboDOX as a competitive weapon, even as the modem market shifts from new subscriber land grab to convincing existing customers to by the latest, greatest product.

"There hasn't been much of a replacement market, and as the rate of subscriber additions flattens, vendors are looking at their unit shipments potentially flattening, and are saying, 'What can we do about this?' " he noted. "They have got 13 million installed cable-modem customers — what would get them to buy another box, like many folks buy another cell phone or buy another cordless phone and basically trade up?"