Difference between Storage Area Network (SAN) and Network Attached Storage (NAS)

A SAN is a network of storage devices that can be accessed by multiple servers or computers. It provides a shared pool of storage space. Each computer on the network can access the storage on the SAN as though they were local disks connected directly to the computer. SAN uses SCSI and SATA protocols.

NAS are storage devices that are linked to a network and provide file access services to computer systems. These devices generally include an engine that executes the file services and one or more devices on which data is stored. NAS uses file access protocols such as NFS or CIFS.

What is Storage Area Network (SAN)?

A storage area network (SAN) is a high-speed data transmission network that allows users to access aggregated block-level storage. It allows several servers to access a network of storage devices. Traditional network bottlenecks are eliminated since SAN devices appear to servers as attached drives.

SANs are also known as SAN storage, SAN network, network SAN, and so on. SANs were first introduced in the early 2000s and were initially restricted to enterprise computing. Today, the cost of highspeed disks has steadily decreased, and SANs have established themselves as a staple for increased organizational storage.

Following are the important components of a SAN −

  • Node ports
  • Cables
  • Hubs, switches, directors as interconnect devices.
  • Storage arrays
  • SAN management Software

The deployment of a SAN simplifies the information life cycle management while ensuring a consistent and secure data transport infrastructure.

There are two types of SAN solutions −

  • Fiber Channel (FC) − A high-speed network of interconnected fiber channel switches connects storage and servers. This is used for mission-critical applications that require constant data access.

  • The iSCSI Protocol − iSCSI stands for Internet Small Computer System Interface. It provides the flexibility of a low-cost IP network.

Both offer benefits based on the needs of an organization.

What is Network Attached Storage (NAS)?

A network-attached server is a dedicated server, often known as an appliance, for file storage and sharing. An NAS device is a hard drive connected to a network that is accessible via a network address. It serves as a file-sharing server. Still, it does not support other services (like emails or authentication). Even while the system is down for maintenance, it permits extra storage space to available networks.

NAS is a complete system developed for high-volume network systems that execute millions of transactions per minute. For any firm that needs a dependable network system, NAS provides a widely supported storage option.

Following are the important components of an NAS −

  • Head Unit: CPU, Memory
  • NIC, Network Interface Card
  • Optimized operating system
  • File System Protocols
  • Other protocols like ATA, SCSI and FC

Network-connected storage is frequently chosen by organizations looking for the most reliable storage options that can be managed and controlled through their existing network systems. NAS allows businesses and residential computer networks to store and retrieve large volumes of data at a minimal cost.

Difference between SAN and NAS

The following table highlights the important differences between Storage Area Network (SAN) and Network Attached Storage (NAS).

KeyStorage Area Network (SAN)Network Attached Storage (NAS)
Stands forSAN stands for Storage Area Network.NAS stands for Network Attached Storage.
Data IdentificationIn SAN, data identification is done by disk blocks.In NAS, data identification is done by file names as well as byte offsets.
Managed byIn SAN, file system is managed by servers.In NAS, file system is managed by head unit like CPU.
CostSAN is more expensive than NAS.NAS is less expensive than SAN.
ProtocolsSAN uses SCSI and SATA protocols.NAS uses File Server and CIFS protocols.
UsersStorage Area Networks are used in professional and business settings.Households and small to medium-sized companies frequently use Network Attached Storage.
ConnectionsIn a SAN, clients, servers, and storage all require dedicated Fibre Channel connections, as well as a dedicated Ethernet network for file request traffic.An NAS device can connect to your existing Ethernet network with ease.
Backup and RecoveryIn SAN, block-by-block copying technique is used for backup and recovery.In NAS, files are used for backup and recovery.
ScalabilitySAN administrators can increase the performance and storage capacity of a SAN by adding more storage controllers or expanding storage arrays.A high-end NAS can scale up to petabytes using clusters or scale-out nodes; a low-end NAS is not very scalable.


From the above discussion, we can conclude that a SAN is a highspeed data transmission network that allows several users to access a network of storage devices. An NAS, on the other hand, is a dedicated file-sharing server connected to a network that is accessible via a network address.