Recently, Amazon Web Services announced the availability of Amazon EC2 Dedicated Instances to meet the needs of enterprise customers they are trying to lure. After the revamp of their VPC offering, this is another surprise from Amazon aimed squarely at the enterprise customers worried about multi-tenancy. With Amazon EC2 dedicated instances, enterprise customers can get single tenant instances with no one else sharing the physical hardware running these instances. They pay a premium to cover the cost inefficiencies that are associated with such offerings.
After Amazon announced the dedicated instances, many in the Clouderati and media questioned whether it is a cloud or not. Even I debated about whether it is a public cloud or private cloud with fellow members of Clouderati community. My argument is that multi-tenancy is one of the defining characteristic of the public cloud and dedicated instances are single-tenant and hence it is #notacloud (a Twitter hashtag popularized by Sam Johnston to dismiss the idea of private cloud). To be specific, I believe Amazon Dedicated instances are, in fact, cloud but they can only be categorized as private cloud (thereby, legitimizing the very idea of private clouds).
One of the prominent public cloud advocate and founder of Cloudscaling, Randy Bias, wrote a blog post two days back trying to dispel some of the myths regarding Amazon Dedicated Instances. As it is normal in any of the Randy’s posts, this post also offered valuable insights. He dispelled some of the myths regarding Amazon dedicated instances with regards to pricing and security. In fact, I agree with most of what he has said in that post. But I have a problem with how he has implied multi-tenancy to put Amazon dedicated instances in the category of public clouds.
Taking aside the definition of ‘multi-tenancy’ and whether it’s a core property, it should be noted that clouds ‘share’ many resources, of which the CPU/server is only one. They also can share storage, networking, billing systems, etc.
Randy goes on to imply that since Amazon’s dedicated instances share network, storage, billing systems, etc. and, hence, they are still public clouds in the flavor of multi-tenant EC2 instances. If my interpretation of Randy is correct, then I think I disagree with him. I would argue that sharing of servers are equally important while considering multi-tenancy along with network, storage, billing, etc..
Let me try to put forward my, still incomplete, thoughts below and I encourage you to hound on these arguments. Please keep in mind that my arguments below are not just against Randy’s arguments but it was based on what I heard from many other public cloud advocates.
- When the idea of private clouds were introduced, it was dismissed outright because they are not multi-tenant. Public cloud purists (I was one of them at that time) argued that even if the private cloud is hosted on third party datacenters, they are not cloud because it is a single tenant environment. If we use Randy’s arguments above, these hosted private clouds should then be considered to be on par with Amazon Dedicated Instances. Well, one can bring in the scale argument but scale matters only as much as the organization using the private cloud needs it. There is no point in having the ability to scale just because they can. Plus, the third party datacenter offering hosted private clouds should be able to meet the scaling needs of most of the enterprises without adding any capital expenses to these customers. If the hosted private clouds are #notacloud, Amazon dedicated instances are not either.
- If Amazon dedicated instances, where multi-tenancy happens at network, storage, etc., can be cloud, why not managed hosting where dedicated servers share network and billing? Why not VPS where they even share servers? Why not shared hosting? I can go on and on and on. In my opinion, we can only call something as a cloud if it satisfies all of the essential characteristics of a cloud. I do believe in the NIST definition of cloud computing and hence I am ok with considering Amazon dedicated instances as a part of the cloud. Public cloud purists who have an even more puritan view of cloud cannot call a single tenant model as a cloud. Period. If they want to be flexible enough to consider Amazon dedicated instances as a cloud, they have to agree that private cloud is an acceptable use of the cloud terminology.
- From my point of view, this move by Amazon is a great pragmatic move. After their aggressive cloud push, they are finally seeing the market reality and are reacting to it. This, along with the recent VPC revamp, will go a long way in convincing most enterprises (except the ones in a highly regulated space) to use public clouds. It is a big win for cloud computing, in general.
- This move puts more and more pressure on Rackspace and GoGrid who were touting their experience in the managed hosting world as a differentiator against AWS.
- I disagree with some of the criticism on premium pricing of this offering. It is about choice. If some organizations want to pay more money and get a single tenant environment inside AWS, they should be able to do it. For me, being thrift is not a characteristic of cloud computing.
In short, if once attribute characteristics to cloud computing, we cannot change it just because Amazon wants to do differently. Then, we can as well point all the definitions of cloud computing to AWS website and STFU. It is time for us to have an independent definition of cloud computing and let the market pressure push Amazon to play around it. What is happening now is that many of the public cloud advocates are tweaking their definition of cloud computing around Amazon’s offerings. I think it has the danger of diluting cloud computing than any FUD from traditional IT vendors. Any thoughts? I strongly encourage you to poke around my arguments. It helps me because I am not really religious about the cloud definition.
Related articles
- What does Multi-Tenant Mean to You? (securecloudreview.com)
- Cloud Computing & Cost Benefits (cleanclouds.wordpress.com)
- Multi-tenancy: emulation or the real thing? (zdnet.com)
- Dedicated AWS VPC Compute Instances – Strategically Defensive or Offensive? (rationalsurvivability.com)
- Amazon’s cloud new offers dedicated hardware (infoworld.com)
- Amazon offers dedicated servers on EC2 (go.theregister.com)
- Here’s Why Cloud Computing Is So Hot Right Now (businessinsider.com)
- Amazon Web Services Adds an Un-Cloudy Option to Its IaaS (readwriteweb.com)
I think the point is less about what it’s called and more about if it has value to customers. My guess is Amazon released this after customers requested it. Being responsive to customers is a good thing.
The debate about terms is a hangover from 2008. Let’s move on so we can embrace innovation and worry less about cloud washers and hair splitters.
Ray Nugent
CEO Smartscale Systems
Krish,
Agree with you when you say – “…we cannot change it just because Amazon wants to do differently.” But at the same time, the definition must evolve with the changing customer needs to be in sync with time.
Here’s another article on the same topic:
http://www.techno-pulse.com/2011/03/amazon-ec2-dedicated-instances-cloud.html
I would argue that the underlying hardware (and hypervisor) for dedicated machines is still multi-tenant. Just because, for a brief period, it ran instances from one customer doesn’t mean that it is single tenant. When you shut down the instance one from another customer (or many) will start up on the same machine.
The time aspect is significant because it is the variations in demand and load that gives the public cloud the ability to scale economically. If you have a single tenant private cloud the underlying capacity sits idle when there is no demand.
A managed hosting provider running private cloud can still do it. They need not use dedicated hardware for running the private cloud.
Krishnan:
There is often a healthy distrust of IT by the rest of the company because IT often seems more obsessed with building stuff than actually doing things with it. I am reminded of this every time we delve into these “what is a cloud” conversations.
At the end of the day, if you can go to the VP of Sales of offer to deliver him or her their CRM app in a cloud-y way, I will bet more often than not, they will not care if their app is being delivering via private cloud, public cloud, or ponies and pixie dust.
AWS sees a customer problem (aka revenue opportunity) and is moving to address it without getting wrapped around the axle with debates on definitions or purity of cloud vision. Yay AWS.
Customers are not looking to deploy clouds, they are looking to solve business problems like addressing growth, improving margins, managing risk better. AWS gets this and the market rewards them for their insight. On the other hand, the market, and closer to home, your stakeholders, will punish the folks that don’t.
Just my two cents,
Omar Sultan
Cisco
I agree. I was more ranting against the my way or highway puritan positioning.
I agree with Omar. As simon mentioned, the underlying hypervisor still makes it as a multitenant model. I believe the controversy is created by people who does not like the innovative business model of AWS. I am sure it is an important factor to consider the dedicated resources as part of the Cloud definition.
Liked your post (as always), but suspect you might be in part confused by the name of this new AWS offering.
If you don’t think of this new offering as “dedicated servers,” but instead think of it as an “instance placement control option” (you get ability to request that your instance be placed on a piece of hardware where no other instances are currently running or will be running for as long as your instance is running) – it all may become clear. IMHO, this offering does not have any impact on whether EC2/VPC is a true cloud or not, it’s just a confusing name.
Now, whether they selected this name with intent to cause such confusion or confusion happened by accident – this could be an interesting question to ponder.
@somic, I am pretty clear about what it is. In fact, I am not even saying that it is not cloud. I am just arguing against those purists who put the emphasis on multi-tenancy as a differentiating characteristic of cloud computing and hence dismissed all private cloud ideas as non starters. I agree that these dedicated instances are no different from rest of their offerings.