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Backing up or archiving digital video presents a unique set of problems. The data is already compressed, so using hardware data compression to improve storage and capacity will actually backfire, making the files larger. Digital video files are often immense, often filling up an entire 2GB volume, and backup speeds are still relatively slow, making backups a tedious procedure.
In general, backup and archiving solutions are too slow to be used for online digital video (in the sense of being usable directly from the media without restoring to a hard drive first). Few backup solutions short of an actual hard drive can sustain a data rate of over 2MB/sec. The relative speed of a backup device primarily comes into play where a system cannot be tied up for long periods of time (as in a studio environment, where billing is by the hour).
Tape backup is the most popular form. Its advantages are price per megabyte and ease of storage and shipping. Its main disadvantage is speed. DDS-2 DATs can acheive 500K/second, making a 2GB backup at least an hour at theoretical maximum speed. Exabyte 8mm drives are also popular to those who sometimes require output in D1 format; with software such as Knoll Software's Missing Link, Exabyte tapes can be used to transfer high-resolution animations to an Abekas for print to D1. Also, Exabyte shares the advantages of DAT.
yes, i know this isn't secure. pinnacle's orray array of optical disks shows promise in a studio environment where time spent backing up is expensive, particularly where the data is intended to be shipped to another studio where the data must be online and available immediately. its 2mb/sec transfer rate (on the macintosh) and eminent shippability of media facilitates this more quickly than tape. its drawback is price; a list price of over $14,000 for the tower, and $800 per set of optical disks is only cost-effective in time-critical or heavy-use situations.
Another alternative is CD backup. Its advantages are in price and store/shippability, but it's even slower than tape in most cases, and the capacity is limited to 650MB. Developments are maturing in CD arrays and ultra-high density CDs that may make this a more attractive solution in the medium-term future.
SyQuest-style cartridges currently suffer from unuseably-low capacity, although development is underway to improve viability of this format as well.
Another alternative is using actual hard disk mechanisms. This is the least cost-effective and the least shippable of all of the above, but its advantages are speed of transfer, and online storage and retrieval.