How Safe You Ain't

I’ve been retired from the Internet group where I worked for five years, and a lot of water has passed under the bridge. Technology has marched on, innovations made, and software more sophisticated. It’s also made us too reliant and trusting. This reliance and trust on technology is what this article is about.

Although this article isn’t strictly about amateur radio, just about every one of us uses a computer in one way or another. IRLP and other eQSO modes are becoming more popular due in part to the wide availability of broadband connections. According to the latest industry reports, over 40% of US users are hooked up to the net via a broadband connection. The three main interconnections methodologies are asynchronous cable, ADSL (asynchronous digital subscriber line), and NLOS (non-line-of- sight) wireless systems. The latter is the fastest growing. It is, in fact, taking customers away from the other two due in part to its synchronous protocol. In simple terms, the upload is as fast as the download. NextNet is the NLOS leader. Go here for details:
http://www.nextnetwireless.com/products_tech.asp

It isn’t the connection methodology we have to worry about, although that is a concern. Rather it’s the lack on understanding of what goes on behind the protocol. More importantly, it's what you do in you own home when you hook up to whatever device provides you the broadband connection.

In some cases, a HOA, complex owner, hotel management, or other supplier supplies the broadband connection. Thus your interface is just an RJ45 connection mounted in the wall, or attached to a telephone. Even if it isn't, you might think you're well protected. Chances are, you're not.

Depending on the broadband connection methodology, the hardware between you and the Internet, what software you use, and how up set up the software can leave you very venerable to piracy. To put this in simple terms, some of the connections are like party lines, and some like private lines. Even some of the apparent private lines are really multiplexed party lines.

Not all will suffer the following fate, but knowing what might be possible will hopefully get the reader to investigate his or her specific interconnection. Let me give you a couple of actual, real-world examples.

I have a friend in New England who lives in a condo complex. As part of his HOA payment, he gets a broadband Internet connection. The instructions are quite simple, and walk the user through setting up his Internet connection via DHCP (dynamic host configuration protocol). In other words, the host computer supplies the requisite IP address, net mask, and DNS. This is the same protocol he uses at work, so he doesn’t have to change anything between locations. He'd been in the habit of printing documents at home, and letting them sit in the print monitor. Once he got to work, he printed the documents. After one long weekend of hard work, he stored his documents in the printer monitor as usual. However, when he got to work they weren't there. That evening, one of his new neighbors brought a stack of paper over to his condo asking him if they were his. They were. The bottom line was, the new neighbor had his print sharing turned on, and by coincidence the name of his printer was the same as my friend’s work printer.

All of you network pundits will gasp in horror that these poor hapless fellows should have known better. Perhaps, but not all of us have the wherewithal to solve these types of problems on our own. Adding some insult is the Windows XP operating system. If you answer the questions presented in the network setup Wizard, and you don’t have a network background to rely on, the average guy will end up turning on both printer and file sharing. It’s a little harder to do on a Macintosh, but not much harder. This problem occurred because the same hub fed both users, and neither user had a clue to the workings behind their broadband connections.

Think about this example. I have a neighbor whose broadband is cable based. He has a WiFi router made by Belkin connected after the cable modem so his wife can access the Internet on her laptop from the kitchen (see http://www.webopedia.com/TERM/W/Wi_Fi.html ). -- All well and good. My across the street neighbor have a wireless broadband connection, and the identical WiFi router for basically the same reason. The first neighbor brought his new laptop up to show me how good his WiFi worked. He could even get on the Internet at my home, nearly 500 feet away! Skeptical, I decided to look closer. It wasn’t his WiFi! It was my neighbor’s across the street! Both PCs are Windows XP based, and both setup for DHCP. Should they have had password protection? Of course, but neither one took the time to set up the router; they just left it in the out-of-box configuration. After all, we’re dealing with computer neophytes not Novell Certified engineers.

Just because you think you know how your system is setup and protected, it may not be as secure as you think. Neither one of my neighbors had a clue. Do you? There are a few things you can do to protect yourself that don’t cost a lot of money, and will provide you with a fair level of security if you set them up correctly.

Once up on a time, there were hubs, brouters, routers, firewalls, multiplexers, and a host of other network hardware devices. Not to mention a bunch of different protocols that weren't compatible. Nowadays, the distinction is somewhat harder to define, and most devices only support ethernet protocols. Most modern routers have built in hubs, and some have software configurable firewalls too. So here are a few suggestions.

First, buy yourself some hardware protection. Netgear ( http://www.netgear.com) makes an inexpensive cable/DSL web safe router. The wired unit is an RP614, and the wireless unit is an MR814. Belkin and others makes similar products. These routers store the DHCP protocol sent by your ISP, and essentially isolate, or firewall, your LAN (local area network) from the WAN (wide area network).

Buy.com sells the Netgear units for under $30 after rebates (just $12.99 for the wireless unit until mid July). They have a built-in four-port hub in addition to the wireless connections of the MR814. Both units have firewall like protection, and even a good level of parental control. They both support local file and printer sharing. Set up takes about 15 minutes, and is web based. You’ll have no fear of interlopers even on the wireless unit if you set it up correctly.

If you don’t need a wireless router, either don’t set up the wireless ports, or just purchase the wired unit. For further safety, you can assign your own local IP addresses rather than use DHCP. Both the Netgear and Belkin manuals explain how to set up generic LAN IPs.

Turn off file sharing. I’m always surprised how many people have it turned on, and they only have one computer! In good defense, earlier versions of Windows had file sharing turned on as a default. Now that both Mac OS and Windows XP have sharing reconfiguration on the fly, there is no reason to leave it on even if you do share files from time to time.

Sharing a printer is rather safe if it is wired directly to a computer. However, if it is ethernet connected, the aforementioned router is almost a necessity. If you have an IP ready printer, it is always best to set it up with one. If you use a wireless web safe router, and you have a lot of nearby users, you might want to password protect your printer logons. Inconvenient yes, but it is also safer (remember my examples above). Most operating systems can be set up to automatically send the necessary passwords.

Use logon passwords. By the way, a simple return is not a password. That’s the first trick a hacker tries. If you have kids, set each one up with a separate logon. That way you can block access to important files.

Use your screen saver. Both Macs and PCs have a one button screen saver activation. If you walk away even to go to the bathroom, push the button. A good friend came back from the bathroom to his four-year-old daughter asking him what those people were doing on screen, if you get the point.

I’m sure there are other ways to stay safe, and hopefully a few of our resident network engineers will add their voices to this article.

Remember, erring on the side of caution is prudent.

Alan Applegate, K0BG

www.k0bg.com

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