NAS and SAN

NAS

Network-attached Storage

Precisely speaking, it should be called NAS unit(server) because a NAS device need both Hardware(CPU, memory, storage components) and Software(stripped-down OS).

A NAS unit is a computer connected to a network that provides only file-based data storage services to other devices on the network.

NAS Unit

NAS units usually do not have a keyboard or display, and are controlled and configured over the network, often using a browser

Features

  • Allows application server to be optimized by move the storage management task out from application server
  • The storage devices are directly connected to a "NAS-Server" that makes the storage available at a file-level
  • It is often manufactured as a computer appliance – a purpose-built specialized computer
  • Typically provide access to files using network file sharing protocols such as NFS, SMB/CIFS, or AFP
  • Cost is much lower than SAN
  • Flexible and extendable than SAN

SAN

Storage area Network

SAN is a network which provides access to consolidated, block level data storage. It's more infrastructure related.

SAN

A SAN typically has its own network of storage devices that are generally not accessible through the local area network (LAN) by other devices.

Features

  • Allows application server configurations to be optimized by move the storage management task out from application server
  • The storage is made available via a server or other dedicated piece of hardware at a lower block-level
  • SANs often use a Fibre Channel fabric topology. A typical Fibre Channel SAN fabric is made up of a number of Fibre Channel switches
  • SAN protocols include Fibre Channel, iSCSI, ATA over Ethernet (AoE) and HyperSCSI.
  • Faster than NAS