Storage options that compliment in-built computer storage v2

Storage options that compliment in-built computer storage: locally attached, onsite storage, offsite storage, detached storage (Photo by Karen /CC BY 2.0, Photo by Andrew Currie/CC BY-SA 2.0, Photo by NeoSpire /CC BY 2.0, Photo by Stuart Conner /CC BY-ND 2.0)

This is the first in a four part series covering storage considerations for a new business computer. For an introduction to the series, please see this post.

In-built storage is just one option available for computer storage, others include locally attached storage, site based storage, or offsite storage.

As such, selecting the in-built storage for a computer is best taken in context of the various computer storage options available.

For this reason, I’ll first describe the various storage options available, before then providing considerations specifically for in-built computer storage in the following post.

Storage options

When considering the storage options available to a computer, it is useful to differentiate based on physical location of the storage as follows:

  • In-built storage – storage capacity that is built into the computer (e.g. hard disk). This will be the focus of the section that follows, and is directly applicable when selecting a computer.
  • Locally attached storage – storage locally attached to the computer that can be easily attached or removed (e.g. USB attached storage).
  • Onsite storage – storage hosted within the geographic boundaries of your office location/s, with a network connection required for access. This storage is typically shared between users and includes solutions called file servers, Network Attached Storage (NAS) and Storage Area Networks (SAN).
  • Offsite storage – storage hosted outside the geographic boundaries of your office locations. Offsite storage includes services available over the Internet, sometimes called cloud storage. It also includes data centre companies that house storage infrastructure on behalf of customers, accessed via various network connection options.
  • Detached storage (onsite or offsite)  – this is an external storage device that is connected to a computer during data transfer, but then detached and stored onsite or offsite depending on the objective for storage. For example, data required for disaster recovery purposes is best stored offsite, and can be kept detached until required.

The physical location of storage has various pros and cons as summarised in the below table.

Storage options

Storage options: in-built storage, locally attached, onsite storage, offsite storage, detached storage.

in-built storage

At a high level, there are two types in-built storage for a computer; hard disk drives (HDD) and NAND or flash storage (I’ll just say “flash” from here).
In-built storage types

In-built storage types: hard disk drive (HDD) and flash storage. Photo by Kamil Porembiński/CC BY-SA 2.0, Photo by Intel Free Press/CC BY 2.0.

Hard disks drives (HDD) rely on spinning disks coated in a magnetic material to read and write information.
Flash storage has no moving parts and uses an electronic medium for storage. Flash storage is typically offered in three formats, “raw” flash, embedded MultiMediaCard (eMMC), and Solid State Drive (SSD):

  • “Raw” flash – storage is soldered directly to the computers processor, this saves space as there is no need for a physical connector, but means the storage is not upgradeable and requires a specialist to repair. “Raw” flash implementations come with vendor specific storage interface commands. Smartphones and tablets often have “raw” flash.
  • eMMC – much like “raw” flash, however a standard for storage interface and management is defined, with current maximum capacity of 128 GB. As with “raw” flash, smartphones and tablets are a typical target for this type of storage.
  • SSD – storage is arranged to allow concurrent multiple access, resulting in much faster speed. There are two interface options, PCIe and SATA, with PCIe providing significant speed advantages over SATA. SSD storage is built to be easily replaced and is targeted at ultraportables, laptops and hybrid computers.

The following table identifies the pros, cons, and example applications for HDD, SSD, eMMC, and “raw” flash.

Pros and cons for HDD, SSD, eMMC, and “raw” flash

Pros and cons for HDD, SSD, eMMC, and “raw” flash.

It can be useful to know that there are three types of flash storage technologies that accompany the three storage formats summarised in the above table; SLC, MLC, and TLC, listed in decreasing levels of quality. In general, SLC is found in SSD storage aimed at high end computers, and TLC is found in low cost eMMC storage. MLC provides a quality level between SLC and TLC. Controversially, Apple recently swapped MLC based “raw” flash for lower quality TLC based memory in the iPhone, resulting in rumours that this was causing reboot issues.

In the next post I’ll focus in more detail on storage speed differences.