What Is Network-Attached Storage(NAS), and How Does It Work?

Have you ever wondered how businesses shared files and data across computers within a network in the 1980s? They relied on network-attached storage(NAS): a reliable and efficient way to deliver unstructured data to the network-connected devices using an ethernet connection.

With time, different technologies have become prominent, including cloud storage offering cheap online storage. However, NAS still solves the critical business pain point of intuitively sharing files within an organization.

What Is Network-Attached Storage(NAS)?

Network-attached storage is file-level storage that works within the confinement of a network, enabling heterogeneous devices to access unstructured data files such as video, audio, websites, text files, and Microsoft Office documents. NAS's benefits include low-cost implementation, ease of access, and support for high capacity and scalability. It also offers fault-tolerant capabilities and built-in security management.

NAS, when defined, can refer to both the involved hardware and its technology. On the other hand, a NAS device is a single unit that carries out the operations. 

You can think of NAS as a centralized storage system that connected devices can access through a browser-based utility. This means that the NAS doesn't require a display or keyboard attached to it. To access it, you need to use a network-connected device.

Alongside NAS, there are storage area networks(SANs). Unlike NAS, SAN handles structured data(block storage). Next comes a Direct storage device(DAS) which is not connected to the network and requires direct access to storage. Each storage type has its advantages and disadvantages, which we will discuss later in the article.

The benefits of NAS are:

• It offers an easy setup thanks to simplified scripts and streamlined operating systems.
• You get high performance for storing and serving files.
• Easily scalable with the help of scale-out, scale-up, and object storage approach.
• It offers high availability of all connected network devices.
• NAS is fault-tolerant as it supports RAID and other high-level functions for data redundancy and replication.

NAS Device

A NAS device contains hardware, software(OS and protocols), and a network interface that connects the NAS to the network. It utilizes physical storage devices and a Central Processing Unit(CPU) that provides the processing power to manage the file system and network requests. The NAS device connects to the network through a network interface, including Wi-Fi or ethernet cable.

For non-critical data storage and access, many NAS devices contain only single-bay. However, enterprise NAS systems have more than four drives, providing high capacity and RAID(redundant storage containers) -- a virtualization technology that improves data redundancy and performance. This means NAS device consists of anywhere between two to six hard drives, depending on the user's requirement.

As for the operating system, most vendors use their proprietary OS, while others stick to a standard approach using Microsoft Windows or Linux.

What Are NAS Product Categories?

NAS products can be categorized based on their capacity, scalability, drive support, and the number of running drives. These categories are:

• Enterprise: The enterprise NAS products are high-end. They are efficient in storing large amounts of data. As data is crucial, Enterprise NAS uses multiple boxes to spread data and reduce risks associated with data loss. It also supports virtual machine images, clustering capabilities, and rapid access. 
• Midmarket: Small to medium scale businesses rely on the midmarket scale. These are capable of storing terabytes of data but without clustering support.
• Desktop: At the lower spectrum, we have a desktop NAS. These are easy to set up and manage. Small businesses and home users primarily use it.

How Does NAS Work?

To understand how NAS work, we need to know its main components, which includes hardware, software, and protocols.

Hardware

NAS is a server that contains preconfigured storage software. The hardware includes processors, hard drives, and random-access memory(RAM). Also, the hardware can be known as a NAS server, NAS head, NAS unit, or NAS box.

Software

NAS software implementation is different compared to a generic server. The software is optimized to maximize performance while handling two request types: file sharing and data storage. NAS software is bare-minimum and directly embedded with hardware to ensure performance.

Protocols

NAS vendors utilize different protocols. These protocols determine the data transfer method and data accessibility via  the network switch, which is connected to all the devices and manages route requests. At the core, you get two protocols for data transfer, TCP and IP, that working in tandem to provide fast and reliable data transfer. 

NAS box supports various protocols for file formatting transferred across the network. These include: 

• Network File System(NFS)
• Server Message Blocks(SMB)
• Apple Filing Protocol(AFP)
• Internetwork Packet Exchange
• Common Internet File System(CIFS)
• NetBIOS Extended User Interface

What Are the Uses of Network-Attached Storage?

Network-attached storage makes it easy to share data and collaborate for in-house and distributed remote teams. For remote teams to access the storage, NAS require cloud connectivity which modern NAS providers offer.

NAS systems work similarly to the cloud but within the organization local environment. Also, companies can configure NAS as per their requirements deciding how much storage they need, the protocols to access and distribute data, and the ability to implement their own security data rules.

As for NAS scalability, it supports scale-up and scale-out approaches. Also, NAS vendors provide cloud support which gives further flexibility regarding backups and remote access.

In short, organizations can use NAS for:

• File sharing and storage
• As archiving and disaster recovery with NAS array
• Hosting in-house open-source solutions such as enterprise resource planning and customer relationship management
• Testing and developing server-side and web-based applications
• For print jobs and serving email
• For streaming media files, including videos and images
• For hosting virtual desktop infrastructure

NAS is also beneficial for sole home users. They can use it for:

• Media streaming service
• Manage torrenting
• Manage smart TV storage
• Use NAS as a personal cloud server
• Test and develop a website
• Storage for the internet of things(IoT) applications

How to Scale NAS

NAS is scalable and offers different ways for data storage and retrieval.

Scale-Up NAS

In scale-up NAS, backend storage is equipped with the NAS head to provide scalability. As it utilizes scale-up architecture, it is known as scale-up NAS. The backend storage is controlled by a two-controlled system which also determines the scalability of the NAS system. You can compare scale-up to a cargo ship powered by powerful diesel combustion engines. These engines can carry tons of weight -- and all you need to do is add more containers.

Scale-Out NAS

Scale-out NAS takes a different approach where the admin can add more hard disks. It is a more straightforward approach and doesn't require the significant upfront cost required in scale-up NAS. For comparison, you can think of scale-out NAS as adding cargo trucks to your fleet. If you need more bandwidth, you add more cargo trucks.

Object Storage

Object storage builds on top of what scale-out NAS has to offer. It creates scalable storage within the web-scale environment and works well with unstructured data. Also, each object storage is stored with a flat address and hence does not use the Portable Operating System Interface(POSIX) that scale-out and scale-up NAS systems use to manage the centralized files. To streamline quick identification, each object contains metadata that describes the object.

Comparisons: NAS vs. DAS and NAS vs. SAN

NAS vs. DAS

Direct-attached storage(DAS) is a storage type that is not connected to the network and is only accessible by one-specific system. In networking terms, you need to be physically present and hence not accessible through a network to access DAS. The best example is your computer's hard disk drive.

As DAS is connected directly with the said device, they are faster than NAS. The performance comes in handy for the applications such as video games, video editing solutions, and more.

NAS vs. SAN

Storage area networks(SAN) are the high-performance version of NAS with low-latency access to files. To achieve high performance, SAN utilizes servers with fast storage and fiber channel connections through a private ethernet network for maximum performance.

SAN is useful for organizations that need to transfer mission-critical data or data for high-demanding applications such as video editors.

NAS is programmed to handle I/O requests for individual files. In SAN, I/O requests are for contiguous data blocks rather than file level in NAS.

Conclusion: Is NAS Here to Stay?

NAS is undoubtedly a great technology. For now, small and medium-scale businesses benefit immensely by using NAS. However, enterprise NAS is also successful in many sectors, depending on the use case, especially with the introduction of flash storage and hybrid NAS arrays.  High-end NAS devices, on the other hand, support various advanced features, including flash storage, data deduplication, and data replication.

With modern vendors also including cloud support, NAS offers more flexibility. But, cloud storage services, such as Amazon Elastic File System or Microsoft Azure File Service, have captured businesses' attention when it comes to storing and retrieving data remotely.

So, what do you think about NAS? Do you believe it will stay with us in the future or perish to other emerging technologies such as the cloud? Comment below and let us know.

Frequently Asked Questions(FAQ)

Why Do Businesses Use NAS Instead of the Cloud?

NAS offers multiple benefits. They are fast and don't have the latency that cloud storage brings in. Cloud is beneficial, but primarily for enterprise clients. NAS is best suited for small businesses as they can control how NAS functions. It also provides better security, and companies don't have to worry about sharing data with a third party. 

NAS is also easy-to-use, with vendors focusing more on improving configuration and setup complexity. Also, it is relatively easy to scale NAS by adding more drives. 

Lastly, NAS wins big when it comes to price. Besides the initial setup cost, NAS requires less frequent spending than the cloud, where you need to pay monthly to keep access.

When Should Your Business Opt For the Cloud?

Businesses should go for the cloud instead of NAS when:

• They want more flexibility when it comes to remote work
• Access to as much scalability as needed
• Automatic updates and maintenance
• Professional-grade data security and backup

Scale-out vs Scale-up NAS - Which One Do You Choose?

Scale-out and scale-up are different approaches to increasing NAS capacity. In scale-up, you need to invest upfront in your infrastructure and later add storage via backend storage. As for scale-out, you don't have to go heavy upfront and can later upgrade by adding nodes for both performance and capacity.

Also, the scale-out approach supports new NAS boxes, which means more flexibility as it works with old-generation models. In scale-up, you need to transfer data from an old setup to a new one which can cost both time and money.