Cloud Storage Decoded

The cloud is where your end users want to back up and share their digital content. They already use iTunes and Dropbox, and cloud services make sense for mobility initiatives and where non-mission-critical data is involved. And a cloud storage strategy should be simple to set up, right?

Well, no. Cloud storage used to mean simple disk drive replacements like SkyDrive and iDisk, but today there are dozens of product categories. Vendors are trying to meet a diverse set of consumer and business needs, and that's creating confusion. There's a big difference between using bulk cloud storage as an alternative to off-site tape or as an online data repository for distributed applications versus having a cloud service replace an entire backup infrastructure--software, hardware, tape library, and staff. And there's lingering IT resistance to cloud storage, as our InformationWeek 2012 State of Storage Survey revealed.

Despite these issues, more enterprises are giving cloud storage a whirl based on some powerful potential benefits, including no capital expense; good support for mobile workers; monthly, usage-based pricing; easily expandable capacity; and the ability to off-load hardware and software management. To help IT teams sort out the market, we invited 26 providers to take part in our InformationWeek Cloud Storage Buyer's Guide; 14 answered the call. Their responses provide insights on the state of IT cloud storage adoption and the features of most interest to businesses.

In our full report, we include full responses from ADrive, Backup Technology, BUMI, Carbonite, Code 42, Dakota Backup, Dropbox, Egnyte, EVault, EVS, Nirvanix, Symantec, YouSendIt, and Zetta. These vendors span multiple market segments, and we'll help buyers assess which services best fit their requirements.

Comfort Levels

A clear sign that cloud storage has moved past the early adopter phase is the fact that 25% of respondents to our State of Storage Survey have cloud as part of their project plans for the next year, up from 20% last year, with email and archiving the most common applications. Our latest InformationWeek Business Continuity and Disaster Recovery Survey and Public Cloud Storage Survey show similar adoption levels, in the 25% range by year's end.

As with any online or hosted service, security, reliability, availability, and performance are the biggest concerns. A key sign that cloud providers have successfully marketed themselves as price leaders is that the percentage of respondents to our State of Storage poll citing cost as a major inhibitor to cloud use dropped nine points in the past year. In our Public Cloud Storage Survey, only 12% listed total cost of ownership as a reason not to adopt online storage services.

Still, IT managers should dust off their calculators and run the numbers out four or five years. The reality is, the price of cloud storage can easily eclipse the life cycle cost of an enterprise storage system. In a recent column, InformationWeek Reports director Art Wittmann compared a midrange Equal- Logic array with a comparable amount of Amazon S3 storage and found cloud rate drops aren't keeping up with declining hardware prices. That said, operating costs are a wild card, and the calculation is different depending on the service in question.

Buyer's Guide: Cloud Storage, Backup and Synchronization

Storage In The Sky
Our full Cloud Storage Buyer's Guide is free with registration.

This report includes 17 pages of action-oriented analysis. Here's what you'll find:

Get This And All Our Reports

Market Segmentation

Cloud-based storage services broadly break down into three categories, defined by use cases and software requirements: raw storage, backup and business continuity, and file synchronization and collaboration. But there's plenty of feature overlap--many backup products offer mechanisms for ad hoc file sharing and mirroring, and raw storage services can certainly be used to roll your own backup process.

Storage-centric application services higher up the value chain are optimized for a specific set of needs and usage scenarios. Raw storage services, of which Amazon Web Services' S3 (file/object store) and EBS (block storage) are the quintessential examples, essentially amount to having a hard disk in the cloud, where the service acts as an alternative to a networked block (SAN) or file (NAS) device. They essentially serve as storage containers that other applications use; many backup and synchronization services, including Dropbox, use S3 as their storage repository.

Although raw cloud storage is often used with cloud-based applications, it can also serve as an off-site storage repository for a DIY enterprise backup and archiving system--as an alternative to a remote tape vault, for example. Yet as David Chapa, Quantum's chief technology evangelist, cautions, application developers must carefully consider how they incorporate cloud storage since access methods and performance profiles will be quite different from LAN- or SAN-based systems.

Moving up the application stack, you'll find backup, archive, and business continuity services. These are nothing more than software-as-a-service apps in which cloud storage is one component of a larger offering. Like all SaaS products, the cloud hosts the storage as well as the application code, software configurations, and operations staff.

Services are further differentiated between those designed for backup versus those mirroring live data.

Backup services may be optimized for client PCs and, increasingly, mobile devices, servers, and enterprise applications. Here the choice is driven not only by the type of client device but also by the type of data you're dealing with--office files and email versus VM images and databases--and its importance and sensitivity. IT teams also must consider the standard backup requirements of RTO and RPO (recovery time and recovery point objectives) for each data type.

File synchronization and collaboration services mirroring live data were initially aimed at consumers, but, like many online utilities, they've become indispensable business tools. They're most frequently used to share office documents with business partners and synchronize to-do lists among PCs, tablets, and smartphones. Other creative applications include synchronizing system and application configurations, such as custom spelling dictionaries. As synchronization services mature and the cost of storage decreases, many of your end users will find them a suitable repository for their personal files--ensuring their information is always available no matter what device they happen to be using.

The 14 participants in our buyer's guide span the cloud storage spectrum. We sought to separate features into categories: those common across various types of services, relevant to business users and consumers, and those of most interest to enterprise IT. We asked about platform support--which devices and operating systems can access the service; access method, whether a Web-based API, WebDAV, NAS protocols, or FTP/SFTP; user and group management and integration with enterprise directories like Active Directory and LDAP; file size limits, if any; support for mobile devices; data security, both encryption of data at rest and use of SSL or an alternative secure network protocol; data redundancy across multiple data centers; types of backup jobs, including full, incremental, and differential; scheduling options; and more.

All of the business-oriented products feature a central management console, with support for individual user accounts and AD integration. Eran Farajun, executive VP at Asigra, a backup software company that supplies a variety of cloud services, says that integration with pre-existing credentials systems should be table stakes for any enterprise cloud storage or backup offering, and we agree. Most services mirror data across sites, but some don't or charge extra; pay attention to this if you need top-notch service availability and disaster recovery protection.

Decision Points

When selecting cloud storage, do an apples-to-apples TCO comparison. Specific areas to check include the ease with which you can move data between the cloud and on-premises systems, particularly if you may need to pull stored data back in-house. Also look at data availability and the service-level agreements different vendors offer, as well as security and support for customized information management and retention policies. We discuss these in depth in our full report.

For purposes of comparison in our pricing scenario, we assumed a 500-GB data set for companies with no capacity cap. Not surprisingly, all the vendors responding to our guide use a monthly subscription model, often discounting annual commitments, with usage and capacity-based pricing.

However, some vendors offer unlimited storage for a set price, averaging about 25 cents per gigabyte per month, while others allow for capping or throttling bandwidth usage at the client, helpful for those worried about clogging undersized WAN circuits. Carbonite automatically cuts upload speeds once a particular backup job exceeds 35 GB or 200 GB, depending on the service plan.

Three Ways

To Use Cloud Storage

1. Want off-site backup? If so, do you need to protect PCs, Macs, mobile devices, servers--or all of the above? Ensure your VMs and hypervisor platform are supported. 2. Want a file sharing platform or collaboration and cross-device synchronization? Decide if you need a local copy of data or can restore directly from the cloud. Opt for services with at least iOS and Android support. 3. Want an off-site data repository for a custom app or DIY backup? Cloud backup means adopting a new set of software and processes. If you're happy with the system you have, consider integrating a service like Amazon S3 into your existing stack.

Align the price of a backup service plan to the value and timeliness of the data. Active, recently used data needs a service with higher reliability--for example, replicated to two or more physical sites--and shorter guaranteed RTOs. If using the cloud for long-term archiving, look for services that automatically migrate older, less-used data to less-expensive storage tiers, with associated lower monthly rates.

Finally, don't forget the growing importance of mobile devices for both ad hoc file sharing and backup. Before signing up for a cloud backup service specifically tailored to mobile devices, check your mobile device management suite. MDM systems, which manage everything from device configuration to security policies, often include a backup component sourced from one of the cloud providers we've profiled.

Conversely, if you've settled on a cloud backup provider for PCs and are shopping for an MDM suite, ask whether the product's backup capabilities can be integrated with the cloud service you use for PCs. And when evaluating cloud file sharing--in contrast to backup services--opt for those with a mobile client. The more you can simplify the service and give users one provider to deal with, the better your adoption rates.

Let's face it, drop-shipping mobile and home-office-based employees external disks and expecting them to be diligent about backing up their data was always a risky proposition. Just as music and movies have migrated online, cloud storage has evolved and matured to the point that many users see it as just another location for their data. This is one area where consumerization can benefit IT.

InformationWeek: Apr. 23, 2010 Issue

Download a free PDF of InformationWeek magazine
(registration required)