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What People Are Asking About Personal Digital Archiving: Part 2

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“Question Time,” on Flickr by Kalense Kid.

During Preservation Week 2013, I gave a personal digital archiving webinar in which over 600 people participated. Ninety one people submitted questions online and two-thirds of the questions centered on two topics: digital photos and storage. In part 1 of this blog post, I gave sample questions and answers about digital photos. Today I will give sample questions and answers from the webinar about digital storage.

What portable hard drive do you recommend for backup? Can you recommend a solid state mass storage accessory drive? Are external hard drives any more reliable for backups than CDs, flash drives, or any other media format?
At the Library of Congress, we cannot make product recommendations but we can talk about the general considerations you should be aware of for digital storage.

Hard drives are not exactly more reliable than other formats; they can still be damaged. But external hard drives do have a larger capacity than most other consumer storage devices, so depending on how much stuff you have to back up — if you don’t have unusually large data-storage needs — you could probably fit everything onto one external backup drive instead of several CDs or flash drives.

The “flash” distinction gets a little fuzzy because some solid-state (no moving parts) external backup drives are essentially large-capacity flash drives that can hold (as of July 2013) up to 1 TB. To reduce your risk of loss, try to fit your entire personal digital collection onto one storage device and backup your collection onto a second device  in case something happens to the first. This may seem extreme but institutions routinely practice backup-drive redundancy. Unforeseen things happen and you should be prepared.

There is no “best” storage medium. CDs, DVDs, flash drives, solid-state drives, spinning-disk hard drives, tape and networked cloud storage all have benefits and drawbacks. CDs and DVDs are light, flat and easy to store but they can be scratched and damaged. Flash drives do not have the moving parts that spinning disks do but they are more affected by extreme temperatures. Spinning-disk drives – the kind that “whir” when you turn them on – have a large storage capacity but you could easily damage them  just by dropping them.

The best strategy is to backup copies onto at least two different types of media and store a copy in a different geographic location in case some disaster strikes your home or office. In fact, professional photographers – who have a financial stake in the accessibility and safekeeping of their digital photographs – have a “3-2-1” rule: make three copies, store two on different types of media and one in a different location.

Also, a general rule is to keep storage devices in the same environment that you would be comfortable in — not too hot, not too cold and not too humid. Keep them out of the attic or a damp basement.

Be aware that all storage devices eventually become obsolete (think of floppy disks). Therefore, in order to keep your files accessible, you should move your collection to a new storage medium about every five to seven years. That’s about the average time for something new and different to come out.  Keep migrating your collection forward to new media periodically. Even if there is nothing profoundly new on the market in seven years, any storage device can wear out if you use it enough so you might want to just buy a new version of the same old thing.

Cloud services relieve you of the responsibility replacing storage hardware. The possible drawback to cloud storage, though, is that your collection may become inaccessible if the network connection is disrupted. Also the cloud service might fall victim to malicious hacking or it might go out of business. No online backup service is as reliable as a storage device that you can see and touch. Cloud storage should only be a secondary backup option.

If you take responsibility for your digital collection and manage it wisely, your collection will always remain accessible.

Is it OK to store the disk or flash drive in a lock box that is fire proof?
It shouldn’t be a problem. However be careful that the lock box doesn’t get too hot or exposed to too much humidity. The general rule of thumb is to keep storage devices — as well as paper photos — in an environment that you would also be comfortable in. Not too hot, not too cold and not too humid.

LOC Wayback machine – can this be used for archiving collections?
Yes. But use it or anything similar — such as cloud storage — as a secondary backup, never as the main place to store your stuff.

Are there any benefits to “archival quality” CDs or DVDs or will regular ones do fine?
Gold CDs are better, but they still fail. If your archive relies on CDs, use CDs from two different manufacturers in case you get a bad batch.

What is the average lifespan of a DVD and do certain types of DVDs have a longer lifespan?
It is difficult to say how long DVDs will last. A lot depends on the conditions under which you store the DVDs, how much you use them and other factors. Take a look at our PDF brochure on the lifespan of storage media.

Is a hard drive for back-up of photos better than a flash drive?
Neither one is superior to the other as far as being better for backup. Storage drives are just containers and digital photos are just files for them to contain. Drives don’t care about file types; a file is a file. External hard drives tend to have a larger storage capacity though, so you can fit more photos on it.

With digital files and containers having so many problems — but with storage cheap — why get rid of anything? Is that really a limiting factor?
The answer is both philosophical and subjective. It’s certainly a conversation starter. Whether you save everything or not is really up to you. One possible disadvantage to saving everything is that there will be more for you to muddle through when the time comes to find something, especially if you have many drafts of documents and many copies of photos and videos and you’re looking for the one good copy. The archivists that I work with are fanatical about sorting, evaluating, keeping and tossing, so their advice would be to not keep everything. But it really is up to you. In fact I wrote an article for Public Libraries Online about “Dealing with Digital Clutter.”

Can you talk about best practices for “automatic” cloud storage methods or commercial services? Why is cloud-based storage best used as a back up?
We can’t comment on specific products but it seems that any automated backup service is a good one; the less work you have to do, the better. I agree that online storage is convenient and often it is the only option for transferring files to someone when the files are too large to send as email attachments. When it comes to digital preservation and personal archiving, remember that no online backup “cloud” service is as reliable as a backup drive that you can see and touch. There are events beyond your control that could happen to online storage, such as malicious hacking or disruption of Internet connectivity. That’s not to say these things will happen, but there’s a risk of them happening. Cloud storage should only be a secondary backup option in addition to having a backup drive or two.

There was talk ten years ago of “The Pulse” wiping out our computerized storage. Any truth to this possibility? Can exposure to magnetization erase photos from CDs or DVDs?
CDRs or DVDR’s should not be affected by large magnets, unless subjected to very high heat at the same time. Commercially pressed CDs and DVDs are not affected by magnets. Magnetism cannot erase data from CD/DVDs because the data is burned on.

Comments (5)

  1. I’m surprised Millenniata discs (M-Discs) were not mentioned in this article. I think they are a very good solution to personal digital archiving. They are still reliant upon the availability of DVD disc drives but I would argue that the market has been so saturated with drives that they will be around for a while. The one drawback is that they can only store 4.7 gigs of data, but for a personal archive I think they are a great solution; much better than dye layered discs and flash drives.

  2. Hi Mike, thanks for the sharing. The information is useful and also interesting to people like me who has just started on the learning journey in Digital Preservation. Thank you.

  3. Mike’s statement that “No online backup service is as reliable as a storage device that you can see and touch” is too strong. Even a generic cloud storage service like Amazon S3 offers 99.999999999% durability: if you store 10,000 photos in S3, you’re likely to lose only one photo every 10 million years. I haven’t seen any other storage media that can make the same claim.

    • Kai,

      You may be correct about my statement being too strong.

      I recently heard a loose comparison between keeping your data in a cloud and keeping your money in a bank. That metaphor only holds up so far but the point is clear, that maybe we should consider entrusting data to a dedicated service rather than storing it at home.

      I think we’re not completely to that point yet though. For those of us that have over 1 TB of data (I have a lot of personal videos), consumer broadband needs to improve to the point where we can reliably upload and download that amount of data in a reasonable amount of time without the connection timing out or — in the case of satellite-dish internet — running up costs through data-traffic charges.

      Also, the pricing structure for online storage services still varies wildly, from low monthly usage fees to high cost-per-MB storage. The cost of storing 2 GB per month can be enormously expensive and prohibitive with some services, let alone the cost of storing 200 GB or more.

      So I agree with you that my statement “No online backup service is as reliable as a storage device that you can see and touch” may be too strong. The key word in that sentence is “reliable.” Maybe, for now, “practical” is the right word.

  4. Regarding the first comment, the new blu-ray mdiscs are out, increasing the size by 5x over the previous DVD version, moving from 5G to 25G. This new size increase has made it feasible and cost effective to create my own permanent home-movie/photo archive. Plus, you no longer need a special drive, nearly all are blu-ray drives are m-ready now. Since the things last so long….hundreds and hundreds of years, I’m expecting only to add to the collection, and no longer have to fear “bit rot” if I don’t re-archive. 100G and 200G Blu-rays are on the horizon, which means only 10 or 5 disks for that terabyte!

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