Benefits of Content-Addressed Storage

Content-Addressed Storage (CAS) has emerged as an alternative to tape and optical solutions because it overcomes many of their obvious deficiencies. The features and benefits of CAS include:

1. Content Authenticity: It assures authenticity by generating a unique or special content address for stored objects. Content authenticity is assured because the address assigned to each piece object stored is as unique as a fingerprint. CAS uses hashing algorithms and if any data is lost, it is recovered from mirrored data.
2. Content Integrity: It refers to that the stored data is not altered. Use of hashing algorithm also ensures integrity too. CAS supports parity RAID protection in addition to mirroring.
3. Location Independence: CAS uses a unique identifier that applications use to retrieve data. It uses a content address to access contents for applications making the address transparent.
4. Single Instance Storage: The unique address is used to guarantee the storage of only a single instance of an object. This address is derived from the binary representation of the object. If the object is already on the system, it is not stored, rather only a pointer to that object is created.
5. Retention Enforcement: Retention and protection of data is highly important. CAS creates 2 immutable components:
   • Data object and
   • Meta-object.
   Data and meta objects are available for all stored objects. The meta-object stores object’s attributes and data handling policies. For systems that support object-retention capabilities, the retention policies are enforced until the policies expire.
6. Record Level Protection and Disposition: All fixed data is stored in CAS once and is backed up with a protection scheme. The array is composed of one or more storage clusters. Some CAS architectures or design provide an additional protection by replicating the content onto arrays located at a different location. Disposition helps in backing up of data and provides security.
7. Technology Independence: CAS works on almost all platforms of technology. The CAS system interface is impervious to technology changes. As long as the application server is able to map the original content address the data remains accessible and can be used.
8. Fast Record Retrieval: CAS maintains all data in discs. Random disc access in CAS enables fast retrieval.