f bandwidth available to subscribers. Based on bandwidth alone, it would seem that 200 cable modem subscribers sharing a 27-Mbps connection would each get approximately 135 Kbps of throughput, which is not much better than a 128-Kbps ISDN connection (Salent, 1999). However, unlike circuit-switched telephone networks where a caller is allocated a dedicated connection, cable modem users do not occupy a fixed amount of bandwidth during their online session. Instead, they share the network with other active users and use the network's resources only when they actually send or receive data in quick bursts. So instead of 200 cable online users each being allocated 150 Kbps, each user is able to use all the bandwidth available during the short period of time they need to download their data packets. Another bottleneck in cable data networking is the interconnection currently being used between the cable modem connect and the subscribers PC. A splitter is used to split the coax cable in the subscribers home into two lines, one for the TV set and another for the cable modem. Cable modems are external devices that connect to the coax cable by way of a standard F port connector (Barnes, 1997). Ethernet10Base-T twisted-pair wiring and RJ-45 connectors are used to connect the cable modem to the PC. The twisted pair wiring from the cable modem connects to the RJ-45 jack of a 10Base-T Ethernet card that has been installed in the subscribers PC. While cable modems can receive data at speeds up to 30 Mbps, the PC itself is limited by its Ethernet interface. Ethernet theoretically runs at 10 Mbps but is usually much slower, typically a maximum of 4 Mbps (Barnes, 1997). Because most home computers do not have an Ethernet card installed, cable operators must typically install one when connecting a new customer for cable modem service. Suprisingly, this seemingly simple procedure presents a major bottleneck in the cable modem installation proce...
