Managing End-to-End Enterprise Storage Solutions Page 4
Storage Area Networks (SANs)
A SAN involves a complex web of servers and storage devices which are linked via an I/O connection, such as Fibre Channel. As storage capabilities are becoming enormous and I/O is handled rapidly, the performance, availability, and reliability of SANs cannot be disputed. The speed of Fibre Channel and the capacity of SAN Systems supply enterprises with fast access to an abundance of stored information.
By deploying a SAN solution, an architecture is also created in which storage devices are separate from file and application servers directly accessed by users. Also, network traffic and congestion is reduced by the isolation of the storage array from the network. In addition, because SAN arrays are connected via Fibre Channel, the bandwidth for storage requests by clients is increased. However, a period of delay in file serving is created, since all I/O requests submitted to the application servers for file access must pass over the SAN array.
SANs versus NAS
SANs are most appropriate for providing immense storage capacity to very large enterprises. SANs also offer minimal network interference. Furthermore, given the capacity and speed of SAN systems, one naturally questions how NAS could possibly offer any advantages over SANs. NAS systems offer comparable performance and provide enterprises of all sizes more than enough storage capacity for current and future needs, so neither solution enjoys an edge in these two areas. However, because SANs require significantly more IT planning and network downtime for installation, the advantage of NAS over SANs is evident in the ease of installation and maintenance. Additionally, NAS offers cross-operating system file sharing and storage pooling. Because these features aren't currently available in SANs, SAN implementation (as opposed to NAS implementation) restricts future business investments in technology and enterprisewide file sharing,
Summary and Conclusions
In terms of network management, information is growing faster than ever predicted, posing considerable challenges to enterprises. Several storage solutions are available to help enterprises overcome the multitude of challenges associated with information growth. These solutions can be grouped into three distinct categories: Server Attached Storage, Storage Area Networks (SANs), and Network Attached Storage (NAS). Among these solutions, NAS enjoys several advantages in that it is easier to install and maintain, provides superior performance, and offers ample storage capacity.
John Vacca is an information technology consultant and internationally known author based in Pomeroy, Ohio. Since 1982, John has authored 39 books and more than 485 articles in the areas of advanced storage, computer security and aerospace technology. John was also a configuration management specialist, computer specialist, and the computer security official for NASA's space station program (Freedom) and the International Space Station Program, from 1988 until his early retirement from NASA in 1995. John was also one of the security consultants for the MGM movie titled : "AntiTrust," which was released on January 12, 2001. John can be reached on the Internet at firstname.lastname@example.org.