Storage Area Network (SAN) and Network Attached Storage (NAS) are two popular storage system approaches that are designed to manage data storage centrally and share stored files among multiple networked devices at once. Both approaches have their trade-offs, so it is important to understand when to use one or the other.
What is a Storage Area Network (SAN)?
A Storage Area Network (SAN) is a dedicated, high-speed network that attaches storage directly to an operating system, centralizing storage devices so they are easier to manage and communicate faster over media. SANs are primarily used to prevent storage-related network traffic from reducing the performance of other traffic on a primary network.
Key features and benefits of SAN
- Improved Network Efficiency: dedicating a network solely to storage-related functions allows performance to be tailored, and reduces demand on the primary network.
- Enhanced Reliability: SANs more easily allow the elimination of single points of failure in both hardware resources and network architecture.
- Centralized Infrastructure: SANs centralize storage devices and the clustering of servers, potentially achieving easier and inexpensive centralized administration.
Limitations of SAN
- Complexity: Even basic SAN solutions can be complex to implement and maintain, requiring dedicated hardware, software solutions, and a dedicated network architecture to provide the best possible performance.
- Cost: Storage area networks will require the purchase of compute, storage and networking hardware. It will also have administration or IT costs associated with installation and maintenance.
- Cost Efficiency: SANs are much more cost-efficient at larger scales. Smaller-scale implementations make it harder to justify the upfront costs.
What is Network Attached Storage (NAS)?
Network Attached Storage (NAS) is a centralized file server that allows multiple users to store and share files over a network. It is also commonly known as a NAS box, NAS unit, NAS server, or NAS head. It is important to note that several NAS systems may be used within a SAN. NAS systems are also commonly used to support cloud storage providers, acting as a data backup, archiving, and disaster recovery system.
Here are some key components of a NAS:
- Storage Drives: Hard disk drives or solid state drives allow the NAS to store large quantities of data. More and larger drives are used to increase the capacity.
- Network Interface: Typically, the NAS is connected to a network via ethernet, Wi-Fi, or fiber optic connections.
The NAS at its core is a file server. So, it runs an operating system just like other computers. This OS may be configured to only allow the relevant processes and network activity necessary to allow access to the stored files.
Key features and benefits of NAS
- More Storage Space: A NAS device will add sufficient storage space to a local computer, thereby boosting the available storage space for total efficiency.
- Centralized Storage: When using, storage devices are physically colocated. The files being stored are accessible in one location for multiple users.
- Automated Data Backup: NAS devices can utilize RAID hardware or automated software to back up the stored data. This data redundancy eases the recovery process in the event of data loss.
- Remote Access: Since NASs are connected to the network, they can be located in a different place than the user accessing it.
Limitations of NAS
- Network Dependency: The performance of a NAS is limited to what the network it is connected to can provide. Highly congested networks will lead to degraded performance. Power outages can affect access to files, and a large amount of network bandwidth is needed to store large files. A constant internet connection is needed.
- Limited Scalability: NAS capacity is limited by type and number of drives they support. Large scale storage may require the purchase of several NAS systems. Predicting costs over a long period can be difficult. Low initial costs can quickly spiral out of control if your business, and storage needs, grow rapidly.
Key differences between SAN and NAS
- Implementation: A SAN is a dedicated network, while a NAS is a system connected to the network.
- Cost and Complexity: SANs typically are more costly and complex upfront than a NAS.
- Performance: A SANs performance is affected by the capabilities of its networked hardware. A NASs performance is affected by its connected drives and network interface
- Management: SANs require full hardware, software, and network administration and support for multiple systems. NASs only require support for their system, which may be part of the upkeep for a SAN.
- Scalability: SANs are designed to more easily facilitate large scale storage operations. NASs are much easier to use on a smaller scale, and scaling up typically requires more NAS systems.
Choosing the right storage option for you
Both SAN and NAS have their advantages and disadvantages, and the choice between the two often depends on the specific needs and budget of an organization. Understanding your requirements and needs is important when deciding what your approach to centralized storage is.