So whether you're just getting started with learning about deduplication, or you think you know everything about data dedupe, take our deduplication explained quiz. If you got more answers wrong than you hoped for, it's time to hit the books and read our data deduplication tutorial.
1. This technology is the reduction in size of data in order to save space or transmission time. It is sometimes confused with data deduplication. It can be performed on just the data content or on the entire transmission unit.
2. This is is the removal of redundancies from data before or as it is being written to a backup device. Critics say it can slow down the overall data backup process because these types of devices are in the data path between the servers and the backup disk systems.
3. This is the process of minimizing the amount of data that needs to be stored in a data storage environment. It can increase storage efficiency and reduce costs.
4. This type of deduplication removes redundancies from a backup transmission as it passes through an appliance sitting between the source and the backup target. Both intelligent disk targets (IDTs) and virtual tape libraries (VTLs) use this type of deduplication. An advantage of this method is that it allows you to use any backup software that the device supports.
5. This type of deduplication can prevent redundant data when backing up data to multiple deduplication devices. With this type of deduplication, when data is sent from one node to another, the second node recognizes that the first node already has a copy of the data, and does not make an additional copy.
6. This is the removal of redundancies from data before transmission to the backup target. These types of deduplication products offer a number of benefits, including reduced bandwidth and storage usage. No additional hardware is required to back up to a remote site and many source deduplication products also support automation for offsite copies. On the other hand, this deduplication method can be slower than target deduplication, especially for large amounts of data. Because of the increased workload on servers, overall backup times may increase.
7. This technology is also known as asynchronous deduplication. It is the analysis and removal of redundant data after a backup is complete and data has been written to storage. It can be contrasted with inline deduplication, a process in which redundant data is identified and referenced (instead of copied) while the backup is being written.
This was first published in June 2010