"The telecommunications infrastructure of the public switched network is likely to be less robust than the Internet. Although the long-haul telecommunications infrastructure is capable of dealing with single-point failures (and perhaps even double-point failures) in major switching centers, the physical redundancy in that infrastructure is finite, and damaging a relatively small number of major switching centers for long-distance telecommunications could result in a fracturing of the United States into disconnected regions. Particular localities may be disrupted for a considerable length of time. . . . Note also that many supposedly independent circuits are trenched together in the physical trenches along certain highway and rail rights-of-way, and thus these conduits constitute not just "choke points" but rather "choke routes" that are hundreds of miles long and that could be attacked anywhere."
- The Broadband Availability Gap, OBI Technical Paper No 1, Glossary, at 135 (full-text).