What is cable modem?
A cable modem allows a single computer (or network of computers) to connect to the Internet via cable TV network. The cable modem usually has an Ethernet LAN (Local Area Network) connection to the computer, and is capable of speeds exceeding 5 Mbps.

Typical speeds are generally lower than the maximum, but since cable services by all districts in LANs that share the same bandwidth. Because of this "shared-medium" topology, cable modem users can access the network slightly slower experience during periods of peak demand, and perhaps more susceptible to risks such as packet sniffing and unprotected Windows users to share than other forms of connectivity