Compression (Compressed)

The reduction of the size of a data set, such as a packet or file, so that it requires less storage space or can be transmitted with less bandwidth. Compression is carried out in software (software compression) or dedicated hardware (hardware compression). Software compression speed is dependent on computer processor power, whereas hardware compression potentially gives superior performance without loading the host system and is transparent to the user. Data transfer speed and total storage capacity are affected by the data compression achieved. Compression is a process of removing fine-grained redundancy from data prior to storing or transmitting it. The granularity may vary, but generally compression deals with redundancy in grains of a few bytes. This is as compared to deduplication, which deals with redundancy in a granularity generally in KB or larger. Because of the difference in granularity between deduplication and compression, deduplicated data can generally be further reduced in size with compression techniques. Compression relies on finding patterns in the data. If the data is very random in nature (for example, due to it having been encrypted), the amount of achievable compression will be low to zero.