Multi-tenancy: why you should care

Multi-tenancy: why you should care

Summary: SaaS buyers shouldn't settle for the limited horizons of single-tenancy. Multi-tenancy is the ideal architecture to make the most of the cloud environment, because it continually evolves to keep pace with the collective demands of its tenants.


Dennis Howlett has summarized the story so far in a debate I was having these past few days with Josh Greenbaum, Bob Warfield and assorted other Enterprise Irregulars (and it's not the first time I've debated multi-tenancy). But everyone still seems to overlook the key issue about multi-tenancy, the one factor that makes it an essential prerequisite to demand as an enterprise buyer if you're shopping for a SaaS or cloud solution.

Maybe people miss it because it's so obvious, or perhaps it's because the significance is not yet self-evident. When something changes the landscape so dramatically, it sometimes takes a bit of imagination to see how it will all pan out. Back in the early days of the automobile, who would have foreseen the networks of high-speed roads, the filling stations and the mass production that were going to make this a faster, cheaper, more convenient form of transport than the horse and the railroad?

Today, people look at cloud computing and yet completely overlook the role of the cloud itself in making it what it is. What if early motorists had only ever wanted to drive on their own private land? Automobile innovation would have peaked with the golf buggy. Private clouds and single-tenant SaaS applications are just as limited, and that's why multi-tenancy matters. Yet even Bob Warfield, who's on my side of the argument, can write, "There are two primary advantages to the Cloud: it is a Software Service and it is Elastic." The cloud has a crucial third advantage, and it's no coincidence that it shows up later in the same blog post at precisely the point when Bob is explaining why multi-tenancy matters:

"What would an app look like if it was built from the ground up to live in the Cloud, to connect Customers the way the Internet has been going, to be Social, to do all the rest? Welcome to SaaS Multitenant."

Multi-tenancy matters because it's the ideal architecture to make the most of the public cloud environment. The cloud matters because it's where all the connections are. That's where your customers, your suppliers, your partners and your employees are, along with a wealth of other resources from all around the world. Multi-tenancy provides the best possible platform for interacting in real-time with all of those resources (which is why top online properties like Google, Facebook, Amazon, eBay and others are completely multi-tenant). But more than that, a multi-tenant application runs on a shared platform that is constantly being fine-tuned to succeed better at those interactions.

Multi-tenancy benefits enormously from the magic of something I call collective scrutiny and innovation. When hundreds or even thousands of other businesses are using exactly the same operational infrastructure, all of them benefit from each of the different ways in which they're challenging and stretching that shared infrastructure. All of them have access to the newest functionality that's introduced at the behest of the early adopter minority. All of them benefit from the hardening of the infrastructure after any of them come in contact with a newly detected threat.

The strength of multi-tenancy is that each of its multitude of individual tenants keeps it constantly evolving. This is in direct contrast to single tenancy, the whole point of which is to limit evolution only to those changes that are perceived to directly benefit the individual tenant. Thus single tenancy misses out on innovations and other advances that are being adopted by competitors, partners and third-party services. If everyone were unconnected that may not matter so much but it's hugely important in the cloud, where you may only realize the significance of a new capability when you see it linked up with other resources.

This is before we even start to think about the potential for using pooled aggregate data for benchmarking, validation or trend analysis, along the lines that Dennis Howlett discussed in his weekend blog post. Most of the benefits of public cloud multi-tenancy have not even begun to be explored, much as the huge transformative impact of the internal combustion engine was unimagined at the beginning of the twentieth century.

That's probably why, for now, it may look as though the choice between multi-tenancy and single-tenancy is something that matters only to the vendor. In truth, multi-tenancy matters even more to buyers, because it's what makes the difference between a SaaS application that's destined for rapid obsolescence and one that will continue to evolve with the cloud and all the wealth of possibility that's opening up in the connected Web.

Topics: Emerging Tech, CXO, Cloud, Data Centers, Legal, IT Employment

Phil Wainewright

About Phil Wainewright

Since 1998, Phil Wainewright has been a thought leader in cloud computing as a blogger, analyst and consultant.

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  • RE: Multi-tenancy: why you should care

    Couldn't agree with you more:-)

    • RE: Multi-tenancy: why you should care

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  • Not in total agreement, but close, LOL

    Phil, I see your point, but I don't automatically award that point to the Cloud as I do to Multitenant.

    The reason is I can put a totally single tenant and unconnected app in the Cloud that is the antithesis of your point, and there are still great reasons to want to do that (Software Service + Elasticity). For example, a drug company may put a proprietary but very cpu-intensive protein folding simulation there.

    I can also put an app that has the qualities you speak of into my own data center, which isn't really the Cloud (unless we plan to call everything with an Internet connection the Cloud). In fact, this is the norm for highly connected apps today, as most of them are done in their own data centers rather than in the Cloud.

    Because of this, I accrue your "scrutiny" and "connectedness" advantages more to multitenancy than the Cloud.

    It is a very fine distinction though, I will admit!

    Thanks for a great post,

  • RE: Multi-tenancy: why you should care


    Agreed. As a SaaS vendor, I'll refer target clients to this article. Many buyers though, even if they agree with your logic, will be shackled by their company's data security policies that won't enable them to purchase multi-tenancy solutions.

    When dealing with such clients, our strategy is one of limiting the damage. We offer a "cloud in a box" / private cloud solution and require clients to stay current within 90 days to our multi-tenant SaaS version updates.

    We're trying to stay as true as we can to a pure "no exceptions" multi-tenant solution, but found ourselves unable/unwilling to say "no" to one of the world's largest banks when they said they wanted to use our solution globally but weren't able to purchase a multi-tenant #SaaS solution where data would be stored off premises.

    2) For such clients that absolutely won't consider buying a multi-tenant solution, we offer them a private cloud with strict terms dictated by us designed to mitigate the risk that supporting such one-off customers would slow us down, increase our costs, or result in multiple substantially-different code bases for us to maintain.

    - Justin Hunter
    CEO of Hexawise
  • RE: Multi-tenancy: why you should care

    Hey, if they are going to benefit from it, why not? Gotta run all the angles right?

  • RE: Multi-tenancy: why you should care

    Well said.

    >>Multi-tenancy benefits enormously from the magic of something I call collective scrutiny and innovation

    As a practitioner who has lived the world of single and multi-tenant apps, my observation is that multi-tenancy keeps the vendor focused on doing what is right even when it is inconvenient to do so. The temptation for the business to take shortcuts is quite high in single tenant apps.

    An app doesn?t have to be multi-tenant to be impactful over the long term, but multi-tenancy improves its chances significantly. It?s like evaluating different forms of government - a benevolent dictatorship may work in the short term, but history shows that a democracy works best in the long term.

    Multi-tenancy keeps all entities(buyers, suppliers, partners) focused on the greater good.

    -Arun Srinivasan
    • RE: Multi-tenancy: why you should care


      best practices shared across the apps?
      Or one-size-fits-all solutions?

      joan lim
  • More to the story

    I couldn't agree with you more, Phil. And I think there's more to the story.

    One reason why single-tenancies still exist is that they are inherently more open to a wide range of users and they can all operate under a single configuration. This is ideal for collaboration. But that can be taken to its own limitations especially in regards to security and independent workflows and information management.

    As we see more business apps have a social component, cloud application platforms are going to need to not only be multi-tenant, but also feature community tenancies.

    You still want to maintain segmentation between companies and users, but you also want to be able to leverage the user community as a whole.

    Let's take the federal government as an example. They might have a private cloud in which each department had their own focused tenant. This lets them keep their apps specialized for their own tasks, while also leverage a common architecture and any core apps. But they would also benefit from a bit of cross pollination. Exchanging ideas, working with partners, even internal workforce crowdsourcing. A community tenancy with those kind of applications in mind would be necessary.

    So rather than use yet another platform for community apps, your cloud app platform should be ready to support both multi-tenant as well as community tenancies.

    Derek Cheng
  • Living it every day...

    Phil, this is really well put. We have been doing multi-tenant SaaS ERP for 10 years and take many things for granted. We have climbed an enormous learning curve on how to develop, deliver and optimize a solution that evolves every day with the constantly changing demands our customers face. I don't see how on-premise or single-tenancy can deliver such a low cost and high speed to consume change.

    I appreciate your eloquence.

    - Mark Symonds
    CEO, Plex Systems, Inc.
  • Transparencies of Scale

    Great article Phil and very refreshing. I really like your idea of collective scrutiny and innovation.

    I agree 100% that multi-tenancy is an extremely important issue that customers need to understand if they are to maximize the value of their investment in new technology services. While multi-tenancy delivers economies of scale for vendors, I see it delivering Transparencies of Scale for customers. Cost, reliability, features, security, etc. - customers are brought together in a community via the shared architecture and this increases transparency exponentially. IT professionals work tirelessly to try and create a shared environment in the on-premise/private-cloud world with user forums and groups but at the end the day their environments stand alone and transparency, as well as accountability, is very limited.
  • (late reply) I do not agree


    The statements you make are not at all related to multitenancy. As a producer of standard software packages we do all the things you noted above. We have a communitity where new functionality is discussed and we collect all input for our release planning. This has nothing to do with multitenancy, but 'how to keep your customers up-to-date'.