Back in 2011, the FCC began their Measuring Broadband America project, which aimed to study actual broadband performance in the U.S. They contracted with SamKnows, a British firm, to measure broadband speeds and performance across the U.S. The National Institute of Standards and Technology (NIST) recently published a report (by way of The Register) that summarizes analysis they performed on the SamKnows data, and one conclusion they are drawing is that DSL service, in relative terms, delivers better performance than cable modem service.
Cable broadband service on average is much faster than DSL. According to the SamKnows data, DSL connections average 5.4 Mbps, while cable broadband connections average 13.5 Mbps. But according to the NIST research, DSL connections on average 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 took a look at 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, Daniel Genin and Jolene Splett.
This particular study only focused on cable and DSL broadband. It used the data from SamKnows’ 10,000 measurement units deployed on ISP customers’ premises and 16 ISPs across the U.S. Much more details from this report can be found here.