 SO on. These investments in fiber are too costly for the small rural carriers that NECA reports have an average customer base of only 4,324 access lines. Few of NECA's carriers have more than 10,000 access lines in service, which is the threshold at which these connections become economically viable. LAST-MILE ACCESS NETWORKS www.TechnicalPDF.com Last-mile networks are the portions of a carrier's network that connect subscribers directly to the provider's equipment. The large number of connections usually means that the last-mile networks are the last portions of a carrier's network that benefit from upgrades. The terms "access networks," "last-mile networks," and "first-mile networks" are used interchangeably. Adding Capacity to Access Networks Upgrading access networks involves numerous devices because service to each telephone company and cable TV customer as well as equipment in neighborhood locations must often be changed. This is a challenge for both traditional telephone companies and cable TV Multiple System Operators (MSOs). However, cable TV providers have newer voice infrastructure than traditional telephone companies because the cable TV providers only started delivering these services around 2004. Thus, their voice switches don't require upgrades at this time. However, upgrading cabling and electronics connected to them for higher capacity is costly and complex. One driving force behind upgraded access networks is the need to support more channels of high-definition television (HDTV) and video on demand (VOD), SO that individuals are able to select from a menu of movies and premium television. In addition, customers are requesting HDTV, which requires more bandwidth and complex electronics than standard definition. Data traffic is also driving networks to upgrade compression on set-top boxes. Consumers are additionally consuming more bandwidth by streaming video from Netflix and Amazon, and uploading and downloading both short and long form videos to and from YouTube, Instagram and Facebook. www.Tec