So what makes DSL or cable modem users particularly susceptible to hacks? First, unlike people with dial-up access, individuals who access the Web via DSL and cable modems are usually assigned the same Internet protocol address each time they log on. The numeric address identifies the individual's computer to send and receive data.
Second, DSL and cable modem users frequently stay connected to the Internet for very long, if not constant, periods of time. Hackers can use a scanning device to find a live connection between the user and a corporate network. If the person has a weak or nonexistent firewall, then the hacker can easily plant software on the user's hard drive, allowing the hacker to control the machine remotely.
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