Despite being around for several years, security is still a top issue for cable modem technology

By Owen Ferguson Cable modems have been around for several years, so you'd think most of the security issues surrounding them would have been worked out by now. Unfortunately, that may not be the case.

Direct cable connections to the Internet that are always "on" remain significantly less secure than dial-up access.

Mike Paxton, an analyst with San Jose, Calif.-based Cahners In-stat Group, explains: "Security is a problem for cable modem users because users share bandwidth on a single cable. (And) since your cable modem is always attached to the network — it's always on —that permits problems that other modems don't."

When hooked up to the Internet using a cable modem, a computer is accessible anytime it's turned on. If left running over night, it's accessible. If simply running a word processor, the computer is still accessible through the network. Thus, there's a much larger window of opportunity for anyone who wants to try and gain inappropriate access to the PC an its information.

But that's not the only factor related to cable modems that Paxton sees as worrisome.

"The second major problem is the type of connection that's used by cable connections or any other type of high-speed connection, and that's based on the IP addresses themselves," he says. "For dial-up users, that IP address constantly changes every time you log on to the Internet. But with a cable modem or even with a DSL modem, that IP address never changes, so that's like a fixed target if you had a hacker who wanted to get into your system. And right now, there are no firewalls available if you have a cable modem to protect you from someone who wants to do some hacking."

Supposing someone did manage to hack their way into a system, what are some of the possible ramifications? Paxton says it would be quite easy for a hacker to look at anything on the hard drive and delete or edit files at will. Whether the victim is a home user or small business, their PC may hold files including such things as income tax information, sensitive business data, or any number of other types of information that one wouldn't want a stranger monkeying with.

Not everyone agrees with Paxton about the risks, though.

Mike Schwartz is senior vice-president of communications with CableLabs, a research and development consortium for cable system operators in North and South America.

His position, and that of the consortium, is that there are no security risks associated with the use of cable modems. "None as far as we see, unless you, as the user, leave on your windows file share."

Windows file share, which is designed to allow document sharing over networks, can be a dangerous element of the operating system if it's left on when you use a cable modem. Essentially, it allows anyone else on the same cable connection (that is, the neighbors) to see a computer (and its hard drive, and all its documents) in their "network neighborhood."

Schwartz emphasizes that this is the primary concern for the user. "We've gone through a lot of effort to be as secure as any other network," he says, "However, you still, as a user, need to be mindful of making sure that file share is not on. It's akin to leaving your front door open when you're not home."

But even if that obvious hole has been taken care of, there are still ways for intruders to gain access to a PC, and the cable connection makes it an obvious target. What to do? Paxton has a few suggestions.

"In the past month or so, there have been some products coming onto the market — customer software firewalls more or less — that allow you to further protect your computer from outside intrusion." he says. "Probably the best thing to do is install a password on your PC — password-protect your sensitive files."

But consumers should not have to shoulder this headache, laments Paxton. He says cable providers should do more to protect their customers. "They could be offering a proprietary software firewall or allowing somehow for the IP address to shift. We'll see those things in the next 12 months," he says.

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