Windows Secrets Newsletter • Issue 95 • 2007-02-08 • Circulation: over 400,000

By Fred Langa There are currently 265 different "top level domains" (.com, .edu, .org, etc.) to choose from when registering your domain. What’s best? First, let’s help a reader who’s wondering if he got ripped off in buying a .name domain name. Then: Secure erasures, reliable backups, CD lifespans, and more!

A .name domain works like any other

Have you seen some Web sites with names that end in somewhat unusual designations such as .biz, .info, .name, or .pro? Reader George McDaniel bought himself one such domain name and now is wondering if he wasted his money:

• "I signed up for one of those .name domain names several years ago. I faithfully renew it every two years, even though I have no use for it and haven’t seen any indication so far that people are using them. Do you expect them to be of any significant use in the future, or is this just a gimmick to sell more domain names?"
  

It’s a short question, George, but the answer takes a bit of explaining. That’s because understanding .name domains requires knowing a bit about how the Internet’s domain name system works, and why. It’s worth digging into because it’s part of the fundamental logical infrastructure of the Internet — the very basis of everything you do online, including reading this newsletter! And (I admit I’m a geek) it’s also interesting in its own right.

Wikipedia has a truly outstanding article on the domain name system, but it’s over 5,000 words long. So here’s the fast-forward short form:

In terms of the Internet domain hierarchy, site names are read right to left, and every site name has two or three parts. Consider www.windowssecrets.com, for example. In this case, .com is the top-level domain, or TLD. The .com domain is one of the seven original generic domain names for the United States that date to the early days of the Internet: .com, .edu, .gov, .int, .mil, .net, and .org. Top-level domains were also set up at that time for other countries, such as .jp for Japan.

Each top-level domain contains many, many secondary level domains. In our example, windowssecrets is our second-level domain. But microsoft is also a second-level domain. So is google or itunes or yahoo or any of the millions of other .com names in use.

Some names may also include a third-level domain, which is www in our example. Other third-level domains you may have seen are ftp, mail, forum, and so on.

This basic domain-name setup worked for a while, until the Web boom in the late 1990s. But by the year 2000, some felt that the seven generic U.S. TLD names had become too watered down. Many personal sites, for example, were in the top level .com domain, even though those sites had nothing to do with commerce, which is what .com names were supposed to be for.

So several new TLDs were created to help sort out different types of sites. Four new generic TLDs (.biz, .info, .name, and .pro) and three other "sponsored" TLDs (.aero, .coop, and .museum) were added to the original list of generic TLDs. The sponsored TLDs are a special class; they’re not available to just anyone. But the new generic TLDs (.biz, .info, .name, and .pro) are wide open.

And that brings us, in highly compressed shorthand form, to the answer to your question, George. The .name TLDs are completely legitimate and on an equal footing with .com, .edu, org, or any of the other more-familiar TLDs. Enforcement of the naming system, however, is lax. An individual can still register a .com domain and a commercial enterprise could, in theory, register a .name domain. The sponsored TLDs and most of the 240+ country-name extensions, such as .jp, are more tightly regulated.

Because things are so loose, having a .name domain for your personal site is 100% correct, George. But it really doesn’t gain you much of anything in practical terms.

So, is it a scam? Not at all. Will it become more popular in the future? Yes, probably, but very, very slowly because enforcement of the categories varies. Is it worth it? That’s your shot to call. But at least now you have a context in which to make your decision.

You can see the current list of TLDs recognized as valid by the Internet Corporation for Assigned Names and Numbers (ICANN) in the Norid directory. The ICANN site has an excellent, relatively short description of TLDs. In combination with the Wikipedia entry mentioned above, this should give you a more complete idea of the Internet naming system than I could provide in this limited space.

More on making data unrecoverable

The item "Erasing data to make it unrecoverable" in the paid edition of the Feb. 1, 2006, issue generated some interesting reader mail, including these question:

• "Would encrypting data and then erasing it be more secure, or is the encryption process itself an insufficient overwrite?" —Bill Webb
  
  
• "Will a strong magnet erase a hard drive? Magnetic devices were made to erase video tapes. Of course, magnetic erasure would be used only on drives destined for recycling." —Bob Hall
  

The answer to these and similar questions boils down to "How safe do you want to be?" It’s one of those things that doesn’t have a clear-cut right/wrong answer.

You can achieve a reasonable level of security by using software that employs the "government wipe" technique — overwriting the old data seven or more times with random data. But even then, specialized data-recovery devices may be able to read at least some of the data.

Part of the reason for this is that hard drives aren’t perfect. Head placement can vary slightly over time and from run to run. Although this has no effect in normal operation, it means that areas alongside the normal head positions may contain readable data. In addition, magnetic fields don’t stop abruptly but diminish over a distance. Accessing and reading this off-track data is, in fact, one of the techniques used by high-end commercial data-recovery services.

Encrypting your data beforehand is a great idea, as long as it’s done early in the process. A hard drive that’s set up to encrypt everything from Day One will be very hard for unauthorized persons to recover data from. But if encryption happens late in the life of the drive, then the earlier, non-encrypted data may still be readable.

Yes, a strong magnet will erase a drive, up to a point. Commercial "degaussing" tools use a rapidly-fluctuating magnetic field to scramble the data on a disk and make it much harder to recover. But even there, you’d have to take special care to make sure that every section of every platter in your hard drive was equally exposed to the full degaussing field. Otherwise, you’re wasting your time.

Here’s what I did when I had to discard a hard drive that contained sensitive information on an old e-mail list. This data was always stored in encrypted form to begin with, and that was my first and most important line of data defense. But when the drive was dying and needed replacement, here’s how I did it:

Step 1. I repartitioned the drive, then reformatted it (empty).

Step 2. I used a "government wipe" tool that filled the entire drive with seven passes of random data.

Step 3. I physically removed the drive from my PC, opened the drive housing, and ran a screwdriver tip across both sides of all the platters, scraping off large amounts of oxide.

Step 4. I discarded the disk at a recycling center.

I suppose government-level spooks might have been able to recover some data from that drive, assuming they somehow found it. But the steps I took made the drive extremely safe from any ordinary data-recovery techniques.

Overkill? Maybe. But I didn’t want to take any chances with the personal data.

The bottom line is that if someone really, really wants what was once on your hard drive, there are ultra-sophisticated techniques that can recover at least some of the data, unless you physically destroy the disk by melting it or grinding it into dust.

So you have to ask yourself: How safe do you want to be? Once you answer that question, you’ll know how far you have to go in making your old drives snoop-proof.

There’s lots more information in my InformationWeek article, The "Dead Drive" Security Loophole.

Choosing the best backup software

Reader Dave Davidson asks whether my original advice on backing up a PC needs to be updated:

• Fred, you had a backup approach you wrote about in your LangaList a few years back. Do you feel that that approach and program(s) discussed then are still appropriate?
  

The short answer is "yes." But that’s probably a bit too telegraphic of a reply!

Generally speaking, there are three main kinds of backups: imaging tools, file-backup tools, and rollback tools.

First, there are the "imaging" programs. Imaging tools don’t copy files, per se. Instead, they’re disk-oriented, and make a bit-by-bit, sector-by-sector copy of your hard drive.

This is important: These imaging tools not only capture what’s on your drive, but also the exact placement and order of each bit, byte, cluster, and sector on the drive. When you restore an image, you’re not just putting the files back: You’re actually putting the hard disk into exactly the same state — bit for bit — it was in when the image was made. That’s why, if you image a "perfect" setup (error free, defragged, etc.) then when you restore it, you get that perfect, defragged setup back in one step. In fact, whatever was on the disk, no matter what, will get put back in exactly the same way it was. This is why imaging is the "gold standard" of backups.

Imaging tools include Ghost and my personal favorite, the tool built into Bootit NG. (The same site that offers Bootit NG also provides the stand-alone utilities "Image for DOS" and "Image for Windows.") There are several other imaging tools, too. A Web search will show you the full range of choices.

Moving down a notch, there are the standard file-oriented backup tools, like the NTbackup tool built into XP and available at Microsoft.com in command-line form or GUI form.

File-oriented backup utilities make no attempt to replicate the placement or order of data on your system; instead, they simply focus on copying the files themselves. When used to restore files to the disk, a standard backup usually will do a good job restoring user-created data files, but may or may not get everything — especially files that are in use at the time of backup — 100% back into the same configuration as before.

Better tools use a technique called "shadowing" to try to capture "open" or "in-use" files. This usually works pretty well. But it’s still not as dead-to-rights certain as imaging. And in any case, a standard backup usually will not get your drive into perfect, defragged condition in one step.

Moving down another notch, rollback tools like GoBack and XP’s built-in System Restore work by tracking some or all of the changes you make on your system. This happens in real-time (as you work), on some preset schedule, or when triggered by specific events, such as installing new software.

If you have a problem after installing some software, you may be able to get your system running again using System Restore, because the utility can return your system files to a prior state. But System Restore won’t automatically clean up leftover files and Registry entries caused by the bad install. It also can’t, for example, let you selectively restore just one data file you erased but now want back.

GoBack does offer file-level recovery, but has its own limitations. Even GoBack’s makers clearly state in their documentation that Go Back is no substitute for full backups.

Of course, any kind of backup is better than no backup at all. But if you’re trying to construct a decision tree, consider this: System Restore is better than nothing. A tool like GoBack is better than System Restore. Standard backups are better than GoBack. And "imaging" a drive is better than a standard backup — imaging is as good as it gets.

How to predict CDR and DVD-R longevity

Reader George Butler asks a question that’s increasingly important, since all forms of removable media (floppies, tapes, zip disks…) fade away as they age. What’s the lifespan of the blank CDs and DVDs you use to burn data, music, and whatnot?

If you haven’t thought about this before, you may be surprised — and dismayed — by the answer!

• "Have you ever done an article on the expected longevity of burned CDs and DVDs? It would be helpful to cover such things as how disks from various manufacturers stand up to time, heat, humidity, light, etc. What about various colors, such as green, gold, etc. What effect does burning speed have on longevity? What is involved in burning disks for long-term archiving? Do the disks of any one manufacturer stand out against the competition?"
  

First, just to make sure we’re on the same page: This question isn’t about commercially-produced, prerecorded CDs and DVDs, such as those you buy at music or movie stores. Those have very long lifespans. They’re mainly vulnerable to physical damage to the readable surfaces of the discs.

This question is about CDs and DVDs that you burn yourself (CD-Rs, CD-RWs, DVD-Rs, DVD-RWs). The answer is grim. Some CDs only last for a couple years, especially if they’re exposed to direct sunlight or covered with do-it-yourself glue-on labels. (The ultraviolet in sunlight and the adhesive in glue-on labels can react with and destroy the layer of dye that carries your data!)

The honest answer is that no one really knows how many years these discs will last, because burnable CD-Rs and DVD-Rs haven’t been around long enough. All the studies you see on the life expectancy of CDs and CD-Rs are based on accelerated-aging tests, which are really just a form of educated guess.

If there’s a single, definitive independent source for longevity data on CDs and DVDs, it’s "Andy McFadden’s
CD-Recordable FAQ." It’s huge, free, and is frequently updated with new information. In the nine years it’s been online (an eon in Internet time), it’s racked up over 7 million visits.

If that’s too much data to wade through, then "Is Your Data Disappearing?" may be more to your liking. It’s an article I wrote for InformationWeek that boils down McFadden’s FAQ and numerous other info sources to focus solely on the question of the lifespan of recordable media, including the various types and brands of CDs.
Fred Langa is editor of the Windows Secrets Newsletter. He was editor of Byte Magazine (1987 to 1991) and editorial director of CMP Media (1991 to 1996), overseeing Windows Magazine and others. He edited the LangaList e-mail newsletter from 1997 to 2006, when it merged with Windows Secrets.