Nine Things You Should Know about Document Storage
If computers cannot store documents for subsequent retrieval, they will be no better than calculators. It is the ability to store documents and applications that provide computers their real power. Stored applications and documents can be retrieved and moved to the operating memory of the computer to continue from where they stopped last.
1. Computer systems store applications and data documents/records for later use on such storage devices as hard disks, CD/DVD and USB flash drives. Documents and records are typically created in the operating memory, which is transient, and then moved to the long-term storage devices such as the above.
2. Maintaining too much data on on-line storage devices such as hard disk drives can slow down system performance. Data on these devices are typically stored in a random manner, i.e. contents of a single document can be scattered all over the disk. Accessing the file can mean retrieving all these scattered pieces of data.
3. Typically, most of the on-line data are infrequently accessed. Moving such inactive data to secondary or off-line storage devices can improve system performance. It can also usually save costs as on-line media space is typically more expensive.
4. Secondary storage devices usually consist of robot controlled mechanisms where several or numerous disks storing comparatively inactive data are stacked in a pre-defined order. Upon receiving a system command, a robotic arm in the device can retrieve a particular disk from the stack and mount in on an on-line dive. The data on the mounted disk then becomes available to the system.
5. Off-line storage also consists of removable storage media. In this case, however, retrieving a particular disk and mounting it on-line has to be done by humans. Unlike robotic devices, which perform this task in seconds, humans will typically need several minutes at the minimum to complete the task. Where the off-line media is stored off-site, it will take much longer time to get them on-line.
6. Off-site storage is often adopted to protect data, particularly backup and archived data, from natural disasters such as fire and earthquakes that affect the primary location. It then becomes possible to use these remotely stored data to restore the lost original data.
7. Where the data is mission critical, they might be mirrored on-line in real time so that the duplicate can be used in case the original get corrupted or get lost otherwise. Systems like RAID maintain redundant copies of business data so that required data can always be made available.
8. Data can also be stored on the Web using third party Web storage services. Dedicated storage service providers will typically have the expertise and experience to protect data, and make them available when needed. They can also provide incidental services such as maintaining the data in readable formats for long periods, which can be a problem in the case of electronic data as file formats and storage devices undergo major changes as a result of technology development.
9. Newer storage devices provide higher storage density making it possible to store huge quantities of data in compact solid-state devices exemplified by USB flash drives. Practices like file concatenation and data compression can enhance storage capacities even further.
Document storage is not just a simple issue of storing data on the system’s hard disks. Many factors are expediting a move to centralize storage of data and applications, often in dedicated storage facilities or on the Web. Specialized storage services, whether in-house or third party, can pay more attention to such issues as data integrity, disaster prevention/recovery and maintaining readability of the data.