Cisco CCNA 200-301 – Cloud Computing Part 4

8. Cloud Deployment Models

The last lecture you learned about the cloud service models of infrastructure as a service, platform as a service and software as a service. In this lecture you’ll learn about the cloud deployment models as defined by the Nyst. That’s public cloud, private cloud, community cloud, and hybrid cloud. So the first one to cover is Public Cloud. The definition is the cloud infrastructure is provisioned for open use by the general public. It may be owned, managed and operated by a business, academic or government organization or some combination of them.

And it exists on the premises of the cloud provider. So public cloud are all the really well known cloud providers like Amazon Web Services, Microsoft Azure, IBM, Bloomix and Salesforce. The first three do support all of the different service models. Salesforce specialize in software as a service, but they’re still all public cloud providers. And Public Cloud is by far the most common deployment model.

The next type is Private Cloud. The definition of this is the cloud infrastructure is provisioned for exclusive use by a single organization comprising multiple consumers, for example, business units like departments within that company. It may be owned, managed and operated by the organization, a third party or some combination of them. And it may exist on or off premises.

So Private Cloud could be where you’ve got a large company and they’re providing cloud services to their own internal departments. Those cloud services could be managed by the company themselves, or it could be managed externally by a third party provider. The main point is that these cloud services are dedicated for that one organization. It’s not Public Cloud where anybody can go and use that. Private Cloud works the same way as Public Cloud, but the services are provided to internal business units, usually instead of to external public enterprises. Private Cloud fulfills the cloud essential characteristics. So this is how it’s different than a traditional on premises solution because you might think, well, Private Cloud, that’s a company and they’re owning and managing their own infrastructure and providing support for their own internal departments.

Well, we’re doing that already anyway with on premises solutions. So how is a private cloud solution any different? The reason is that it fulfills the cloud essential characteristics. Those were on demand self service, rapid elasticity, broad network access, resource pooling and memory assured service. So if you think back to the example when I gave you the demo of Amazon Web Services, which was on Public Cloud, well, an organization could develop something like that for their own internal use. With the traditional on premises model, a business.

9. Cloud Computing Advantages

In this lecture, I’ll wrap up the cloud computing section by summarizing the advantages. First one is scalability. Cloud computing provides businesses with the ability to regulate the service in accordance with their current requirements. They can scale the capacity up and down as needed. So this comes about from the elasticity of cloud code. It’s very easy to provision new servers when they’re needed and when they’re no longer needed, it’s easy to turn them down.

This is different than what you would get with an on premises solution. Imagine that a customer comes to you looking for a solution and you can do it. But you would need to buy additional servers and need to buy additional network infrastructure, et cetera. And you look at to see if this is actually going to make money in the long run or not. And a problem you’re going to have is if this is just a one time project that’s going to run for a few months after the project is finished, you’re still going to have that hardware sitting there and it’s not going to be doing anything anymore.

So you had that large upfront capex cost anyway, it’s wasted money. After the project is finished, if you were deploying in the cloud, then you can just spin up those servers as and when they’re needed. So when the project starts, you spin them up. When the project finishes, you bring them back down again. Also, if you already had your own on premises solution, you don’t have to move everything into the cloud. You could keep everything on premises that you were running already. And for your temporary solutions you could run those in the cloud.

So that scalability is a big advantage. Also, it gives you infinite computing capacity on demand. If you can’t run out of room in your data center, what can happen with an on premises solution? There’s unlimited capacity with cloud providers. Also, you get flexibility through cloud bursting, which is similar to what I was saying before. But if you’ve got your own on premise solution, then you can scale out into the cloud as and when needed. And as we mentioned in the last lecture as well. Another possible reason for doing this is maybe you’ve got your own onsite data center for your disaster recovery solution. You could use cloud for that. That would also be a form of cloud bursting.

Next advantage is business agility. Cloud gives you the ability to handle expected or unexpected changes in load. Again, this is similar to what we were just talking about where if there’s sudden demand for additional servers, you can get them provisioned very quickly. New servers can be up and running in around 15 minutes. That’s reduced time to deploy an application into production. So it’s very scalable. It’s also very fast to make those scalable changes as well. Next one is cost efficiency. As a customer you pay just for what you need right now, resulting in directly proportional costs. You don’t have to over provision and then pay for extra capacity that you’re no longer using.

You avoid provisioning and paying for the peak as a permanent fixture. If you think of an e commerce application, they’re going to be busier at Christmas. So if you were running that as an on premises solution, you would need to buy enough hardware, enough infrastructure to support your busiest time of the year.

But the rest of the year that extra capacity is sitting wasted and you’ve already paid for it as a capex cost. So with the cost efficiency you’re moving from that large upfront capex cost to a comparatively small and more manageable monthly opex cost and your ICT costs are more transparent or more manageable to the business as that fixed monthly cost, you do not have depreciable hardware assets. So when you’re using on premises you buy what is the latest hardware. Now a few years down the line that is going to be out of date, it’s depreciated and you’re going to have to do a technology refresh, replace it with new hardware, which again is another big upfront capex cost. The provider passes the hardware maintenance costs onto the customer as part of that predictable monthly fee. There’s no unexpected costs.

Next advantage is this can give you a competitive advantage reducing the capital spend with large upfront capex on infrastructure releases funds to invest in innovation or other priority areas. Organizations can respond quickly to evolving market trends and focus on growing their core business. So this can give your company an advantage over other companies that are not using cloud productivity it staff. This is a big one for us. It staff can focus more on strategic decisions in developing and improving core applications rather than maintaining or troubleshooting hardware infrastructure. Now, if you’re going to be cynical about it, you could think that’s a nice way of saying that you’re not going to need as many It staff anymore to be looking after the hardware infrastructure.

But as network engineers, this is something I hear quite a lot is people worry about well because everybody’s moving a cloud, does this mean there’s going to not be a role for me anymore as a network engineer? But that is not the case at all. You saw when I did the case study with the Ecommerce application and we had to have that network design for how It was going to be deployed. Well, the cloud provider isn’t doing that for you.

You need to have your own in house It who are going to do the design. Also the provider. If you’re using infrastructure as a service, they provide the infrastructure but from the operating system and up that is managed by your own in house staff. So you need to have in house staff that have got the skills to do that. So your own staff need to do the design. They also need to do the configuration from the operating system up, they need to be able to maintain it as well. So cloud does not mean that normal in house It staff are going to be losing their jobs. We still require them.

In fact, when you use cloud and you’re doing the planning to go there, the planning is just like if you were creating a new in house location. So you still need the same staff to be able to do that. Next advantage is availability and reliability. All major cloud providers facilities are located in hardened data centers with redundant power, no single points of failure, and onsite security, the service will be certified to the relevant industry standards such as ISO 9001 and 27001. And the data center is built by facilities, server networking and storage qualified specialists according to best practice. So when you use cloud services from these public cloud providers, you know that their data centers are really well designed.

They’re already proven because we’ve got all those other customers that are already running in there. One thing to know check the service level agreement to see what is guaranteed and the compensation if the SLA is not met. Next one is cost. Here we’re not so much talking about an advantage, although cost can be an advantage, but you need to check if it is going to be or not. So those advantages are all great to have, but when you make a decision whether or not to deploy cloud computing, it’s usually going to come down to the overall long term cost.

The total cost of ownership of maintaining an on premises solution should be compared to the TCO of maintaining a cloud equivalent and the advantages and disadvantages of each factored in when making the final decision. However, it’s not an either or decision. You don’t have to go with purely on premises or purely cloud. In fact, the majority of companies who are using cloud services will have a mix of both on premises and cloud solutions. Okay, that was everything I needed to tell you about cloud computing. I’ll see you in the next.

• Category: Uncategorized