The first article in our three part series on backups looks at the most basic element of the system: the backup device.
As Australia’s health providers slowly inch towards paperless workflows, secure storage and backup of data is increasingly more important.
We start perhaps our most important series of articles with a look at popular hardware options with which to perform the backup of your practice data. These devices have similar if not identical pros and cons across all operating systems and practice software solutions. This series of articles will look exclusively at the backup of clinical data; the larger challenge of backing up entire computer systems is outside the scope of this series.
The second article in the series will deal with the theory of backups, discussing frequency, organisational issues and auditing. The third and final article will detail specific examples with reference to five leading practice software vendors.
A utopian practice data backup strategy will:
- Back up all digital practice data at least daily.
- Allow regular “snapshots” to be created and stored permanently.
- Not be labour intensive for staff.
- Not be cost prohibitive either initially or going forward.
- Allow easy restoration and auditing.
As such, the device or devices that you choose to perform your backups should accommodate as many of these points as possible.
Before purchasing a device to perform your backups, the following information needs to be collected:
The amount of data (i.e. size in megabytes (MBs) or gigabytes (GBs)) that needs to be backed up should be considered first. There is obviously no point opting for a device that won’t fit your data.
Speed of the Device
The time a backup takes to perform is directly related to the amount of data to be copied and the speed of the device. While it is common to have backups run unattended over night (making the device speed irrelevant), this invariably means that in the event of theft or natural disaster, data loss will result. When planning a new backup solution, steps to reduce this exposure need to be made.
While the initial purchase price of a backup device is easily noted, be mindful of additional costs including installation, staff training, additional software and ongoing consumable costs (tapes, disks etc).
The biggest ongoing cost by far will be staff time, especially if regular backup audits take place.
CD & DVD
CDs hold up to 700MB and standard DVDs can store 4.4GB. While the majority of practice databases will fit on a single DVD or CD, practices that store scanned images or other large files as part of their clinical record may exceed these limits.
The speed of CD and DVD drives both for reading and writing data have continually improved. A full DVD can be burnt in under ten minutes using a modern burner with CDs taking less than five minutes.
The cost of blank CDs and DVDs has long been below $0.50, making them the cheapest option for permanent storage. High quality internal DVD drives cost under $100, with external versions coming in at under $200.
It would now be difficult to purchase a computer not capable of reading a CD or DVD, making them an excellent choice in terms of compatibility. If your backup requirements exceed the 4.4GB a standard DVD will hold, you can simply burn multiple disks (or opt to use the uneconomical 8.5GB disks that are also available).
While in use by early adopters already, the next generation of optical devices should begin to proliferate soon. Two competing technologies, Blue Ray and High Definition DVD (HD DVD) are vying to replace DVD as the standard video format. Like DVD, these disks will be able to be used as backup devices with far greater capacity.
The two most common physical hard drive dimensions are 2.5 inch and 3.5 inch. The smaller variety can hold up to 160GB, with the larger format cable of holding a massive 750GB.
There are also proprietary systems such as the ZIP, Jaz and Rev cartridge drives in circulation. In their own right they are good devices to perform backups, however the non-standard nature of these devices limits their compatibility and tends to doom them to obsolescence faster than generic solutions.
Hard drives have the highest read and write speed of any storage device. Coupled with their large capacity, they are an ideal option if you have large amounts of data.
External hard drives based on a 3.5 inch device typically sell for less than a dollar per megabyte making them a very cost effective solution. 2.5 inch solutions are more expensive per megabyte, but typically four times smaller than their larger brothers, making them ideal for transporting data off site. Because of their laptop heritage, 2.5 inch devices typically have higher shock resistance, and most can be powered from the data cable negating the need to transport power adapters.
As well as the enclosed cases discussed above, hard drives can be mounted in caddies that slide into a drive bay (internal or external to the computer) , making connection easier and minimising costs when multiple drives are required.
As the data backed up to a hard drive is unlikely to fill the drive, multiple backup sets should be stored until the drive reaches capacity. When this occurs, the oldest set can be replaced with the current backup e.g. a 300GB hard drive will allow for thirty days worth of “roll back” assuming a daily backup of 10GB. Having multiple hard drives would allow a far greater history to be kept, although ultimately a permanent record will need to be made at least each week, either to a series of DVDs or a tape.
Network Backup Solutions
Network Attached Storage (NAS) refer to hard drives that are attached via a network as opposed to a traditional storage interface (USB, SCSI, FireWire, SATA etc). Once only targeted at larger businesses, NAS products have thrived at the bottom end of the market, and are now a simple and cost effective way of deploying a file server.
For the purpose of performing backups, NAS devices are comparable to other hard drive solutions, although the backup will take longer to run and the device will be more difficult to configure. Due to the inclusion of the network interface and the lower sales volumes, NAS devices are more expensive than portable hard drives. Unless the device is being used for other applications in your practice, purchasing a NAS for the sole purpose of backup is probably not the best solution.
The adoption of broadband worldwide has allowed Internet based backup solutions to proliferate. These are popular in countries with cheap, reliable, fast Internet - Australian medical practices need not apply! The ever increasing size of practice software data files, privacy concerns (founded or otherwise) and the cost of transferring gigabytes of data across the Internet each month relegate this solution to the “future consideration” basket.
Small USB “thumb drives” can also be used for small document backup and transport. These drives are small enough to fit on a key ring and are very convenient for backing up documents quickly or for transferring data between computers when a network isn’t available.
They are relatively expensive per megabyte and the capacity can’t match that of hard drives. Anecdotally they are not as reliable as the aforementioned media, so multiple thumb drives should be used if your practice chooses to use these devices for your backups. As always, permanent backups still need to be made, so a complimentary solution such as a DVD burner will also be required.
Tape has long been the backup medium of choice for large organisations needing to protect significant amounts of data. Depending on the device and the amount of compression applied, several hundred gigabytes can be stored on a single tape.
Tape drives are relatively expensive to purchase, but the individual tapes are very cheap per megabyte. Most medical centres generally cycle through a series of tapes either weekly or monthly, and store a tape for a permanent record periodically (although rarely enough!).
Due to the moving parts in both the drive and media, tape is relatively unreliable and the devices have fairly slow data transfer rates. Further, unlike DVDs and external hard drives, a backup stored on tape can generally only be restored on a single practice computer i.e. the computer with the tape drive. In the event that this device is out of service or has been superseded, the restoration of such data can be time consuming and potentially expensive.
All the devices discussed have strengths and weaknesses, and it is my opinion that none are ideal for clinical data in isolation. If the total amount of data you need to backup is less than a DVD or CD, I recommend burning a new disk each day which create a cheap, permanent backup that can be restored from any computer. Given the rollback that individual DVDs or CDs allow for and the insignificant cost of the disks, there is little justification for using re-writable media.
If the data you need to backup exceeds the limit of a single DVD, consider the option of burning multiple disks or using a hard drive or tape device. Ideally the data will not be over written each night and multiple backup sets will develop over time. Even if hard drives or tapes are used daily, this doesn’t negate the need to burn a series of DVDs at least once a week, or alternatively store a tape permanently.
While it may be a few years before the devices and media become cost effective, Blue Ray and HD DVD are destined to become a promising option to perform backups.
Nathan Coultard is the Director of TechMed , an IT Support company based in Wagga Wagga, NSW.
Posted in Australian eHealth