Telephone companies that have not invested in fiber to the premises (FTTP) offer Digital
Subscriber Line (DSL) service over twisted-pair cabling for Internet access. (Cable
TV providers use other technologies over the coaxial cabling portion of their hybrid
fiber/coaxial cabling plant.) Former telephone companies deploy DSL Access Multiplexers
(DSLAMs) to aggregate traffic from multiple DSL modems in neighborhoods
and combine it into higher speeds before sending it to the Internet or data networks
over fiber-optic cabling. DSLAMs are located in a carrier’s central offices or in remote
terminals, which are cabinets placed between the central office and the subscriber. The
connection between the DSLAM and an ISP is a potential site for network congestion.
If capacity is insufficient, a customer might experience delays.
