Study: Cable falls behind DSL in delivering what it promises

DSL is more likely to deliver the advertised speed than cable broadband, according to a recent analysis of data by the National Institute of Standards and Technology.

The data, collected under FCC contract by Sam Knows to measure broadband speeds and performance across the U.S., shows that DSL connections average 5.4 Mpbs, while cable broadband connections average 13.5 Mbps. But according to the NIST research, DSL connections deliver "download speeds above 80% of the assigned speed tier more than 80% of the time. By contrast, a significant fraction of cable connections received less than 80% of their assigned speed tier more than 20% of the time."

The NIST research also examined congestion factors between the two dominant broadband access methods in North America and found some differences. "While DSL ISP networks suffer predominantly from congestion in the 'last mile,' distribution of congestion in cable ISP networks exhibits a great deal of variability, with a few cable ISP networks congested mainly in the 'last mile' but the majority congested elsewhere, in the 'middle mile' or beyond," said the research authors.

Telecompetitor, July 17, 2013