Study Methodology

Mapping CAF II Network Builds

This study’s purpose is to help local and state leaders better understand the kind of networks being built using CAF II funds. The need for this work was confirmed through interaction with GPS 45:93, East Central Minnesota’s regional economic development coalition, as they considered broadband improvement strategies and were unsure of the real impact of CAF II investment. The region’s lack of broadband is documented on state broadband maps. The Lindstrom and Braham exchanges were selected for study based on GPS 45:93 team members’ knowledge of recent CAF II improvements and provided an opportunity to compare the CAF II deployment strategies of the two dominant incumbent telephone companies within the region.

To help ensure the accuracy of our findings, advice on this study’s design, equipment identification and findings was obtained from several industry experts, including telecommunications engineers, telecom providers, product managers, sales engineers and telecom equipment sales staff.

In addition, the telecom providers which accepted CAF II funding and used it to make improvements in these exchanges, CenturyLink and Frontier, both were asked to review and offer comment on the report prior to publication. Technical documentation of the mapped exchanges, notification of mapping errors in the report, as well as suggestions for alternative examples of CAF II deployments to be included in the study, were specifically invited. Neither company chose to offer substantive comments on the draft. However, CenturyLink did respond to suggest that dissatisfaction with the Connect America Fund program should be directed to the Federal Communications Commission and not those providers that have elected to participate in the CAF program. While saying it had a “number of concerns” about the report, CenturyLink declined to comment substantively, explaining the company did “not want to be associated with something that might be viewed by some as critical of the CAF program.” CenturyLink noted, “Providers are merely following the rules and adhering to the commitments made when they agreed to participate in the program.” ix

Community Technology Advisors conducted the primary field research in the summer of 2017. Using base maps and a GPS-enabled camera to take pictures of various electronics boxes located in public rights-of-way (ROW), improvements within the two exchanges were mapped. Fiber networks, though clearly marked in the ROW with the standard white and orange poles, were not mapped to simplify the mapping process. While a fiber line may be adjacent to a property, access to that fiber would be dependent on the nearest handhole, a junction box where new fiber links to customers can be connected.

Electronics boxes clearly identified as electric utility, railroads or traffic/lighting control devices were not mapped. Where boxes could not be definitively identified, they were assumed to be Digital Subscriber Line Access Multiplexer or DSLAMs, possibly overstating the deployment of electronics and the resulting service areas. DSLAMS are the field electronics that connect between newly deployed fiber lines and the existing copper lines that connect to customers.

Prospective service areas surrounding the DSLAMs were indicated with 3,000-foot radius and 9,000-foot radius circles. As explained earlier, it is likely that customers within 3,000 feet of a DSLAM would be able to receive broadband services at or above 25 Mbps/3 Mbps level; those within 9,000 feet of the DSLAM would be able to receive at least 10 Mbps/1 Mbps.

If this mapping strategy errs, it likely overstates the availability of broadband for three reasons:

  1. Copper lines do not radiate directly from the DSLAM but follow the roads and may, in fact, make multiple turns before reaching the home. Each turn adds distance that in turns limits deliverable capacity. Measurements were made “as the crow flies” as opposed to actual routes likely taken, thereby maximizing the assumption of the radii 3,000/9,000 feet from the node.
  2. Broadband speeds vary greatly depending on the condition of the copper lines from the DSLAM to the home. The age of these copper networks is unknown, but according to industry experts, it would not be unusual for copper lines in rural areas to be at or even beyond the end of their expected useful life.
  3. It is possible that one or more DSLAMs were missed in this field inventory. However, because the study’s purpose is to improve understanding of the level of broadband service generally available to customers served by CAF II-funded deployments, rather than to provide a definitive service inventory for a particular location, we are confident in its conclusions.

On the other hand, it is possible that higher speeds over longer distances can be achieved than assumed in this report. Factors that would enable these speeds include:

  1. High quality, non-degraded copper lines.
  2. Availability of spare copper pairs that would allow two or more pairs of copper lines to be bonded together.
  3. Ongoing technical improvements in electronics and software could allow for future improvements in DSL capabilities.

Despite these uncertainties, we believe that this methodology provides a reasonably accurate picture of the impact of these deployments funded by CAF II subsidies. This confidence is backed up by ongoing conversations with rural broadband customers across the state in community and regional meetings, with many interactions documented through emails and video testimonials.

Impact of CAF II-funded Networks