Storage Techniques consist of 1 important type known as Direct-Attached Storage in which the storage devices are directly connected with the other network devices. The application uses the block level of the access protocols to get access the data. The examples of the DAS are the internally connected HDD of th various hosts, HDD sets which are directly connected with the system.
Efforts to organize this dispersed data led to the emergence of the storage area network (SAN). SAN is a high-speed, dedicated network of servers and shared storage devices. Traditionally connected over Fibre Channel (FC) networks, a SAN forms a single-storage pool and facilitates data centralization and consolidation. SAN meets the stor-age demands efficiently with better economies of scale. A SAN also provides effective maintenance and protection of data.
Network-attached storage (NAS) is an IP – based file-sharing device attached to a local area network. NAS provides the advantages of server consolidation by eliminating the need for multiple file servers. It provides storage consolidation through file-level data access and sharing. NAS is a preferred storage solution that enables clients to share files quickly and directly with minimum storage management overhead. NAS also helps to eliminate bottlenecks that users face when accessing files from a general purpose server.
Traditional SAN environments allow block I/O over Fiber Channel, whereas NAS environments allow file I/O over IP – based networks. Organizations need the performanceand scalability of SAN plus the ease of use and lower TCO of NAS solutions. The emergence of IP technology that supports block I/O over IP has positioned IP for storage solutions.
In the life cycle of information,we create the data and easily edit it, if required. By the passage of time, the data becomes more constant with very less gradual updates. This fixed kind of data is generally used by a lot of applications.
As networking technology of storage is becoming popular, bigger and the very difficult implementations are going to be more general in future. The heterogeneous nature of storage infrastructures has further added to the complexity of managing and utilizing storage resources effectively. Specialized technologies are required to meet stringent service level agreements and to provide an adaptable infrastructure with reduced cost of management. The virtualization technologies discussed in this chapter provide enhanced productivity, asset utilization, and better management of the storage infrastructure.
The mind map for the Storage Techniques is as follows:
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Even though, the implementation of the various storage technologies are becoming popular these days, DAS has been still considered best for the access of the localized data and sharing of those kind of environments where they have very less servers.