Benefits and considerations of using cloud services

- [Instructor] There are several benefits and considerations of using a cloud service, whether that service is Azure or AWS or another service. We're going to touch on some of those benefits and considerations in this lesson. Starting off with high availability, which is a huge benefit when you go to a cloud service. High availability ensures that the systems are available for long periods of time with little to no disruption. What you need to be aware of is what high availability is not, because I have heard high availability interchanged with the next three terms, and the first one is backup or disaster recovery. High availability is not a backup or disaster recovery solution. We'll talk about backup and disaster recovery in a few moments. High availability is not high performance. High availability does not meet the demand in resources, and it definitely is not load balancing. Load balancing spreads load across various resources, whereas high avalibility ensures that those resources are just available. Another huge benefit of cloud services is scalability. Scalability is the ability to scale a resource up. As the workload increases on a resource, that resource can then get bigger or as the load decreases, the resource can then get smaller, and this is on the resource itself. It's not adding additional resources. Adding additional resources is called elasticity. And you'll hear this referred to as scaling out. When the workflow increases, additional resources are provisioned. For example, in the case of a virtual machine, we could provision additional virtual machines to accommodate the load. And then when the work load decreases, we can remove the work load from those additional resources. You'll often hear the term agility when talking cloud services. Agility is the ability to quickly respond to changes, and the cloud is great for this because it allows us to quickly adapt to a change, sometimes within minutes. For example, if we need to provision or decommission a cloud service, we can usually do that in minutes and we can usually do that through self service. We don't have to go to purchasing and order a server and wait for it to come in then build it. That can take weeks. If I need a virtual machine in Azure, I can provision it in about three minutes. Fault tolerance is also a benefit of moving to cloud services. Fault tolerance ensures that services are always up and running, even if there is a failure. And there are two ways that this can be accomplished and most service providers have some type of fault tolerance built in. For example, in the case of Azure, one way fault tolerance has been built in is by having regions that contain multiple data centers. So if something happens to resources in one data center, the other data center can take over. We can also build in fault tolerance into our services ourselves. Remember I mentioned disaster recovery, as well? And the reason that has nothing to do with high availability is because disaster recovery is the ability to recover from a failure. And just like fault tolerance, cloud services usually have some type of disaster recovery built into their offerings. In addition, the cloud service usually provides disaster recovery options for various services, such as you have the option to have backups with your virtual machines or SQL databases. For the exam, you need to be familiar with the term economies of scale and how this is a benefit for cloud services. Economies of scale allow us to do more efficiently at a lower cost and to operate more efficiency at a larger scale than at a smaller scale. This model is used by cloud providers because a purchase large amounts of storage virtual machines, et cetera, and offers slices of those resources or servers at a lower cost. There are two terms that you're going to hear all the time when it comes to cloud services. Those two terms are CapEx and OpEx. CapEx is capital expenses. Capital expense is an upfront cost. For example, if you're building your own data center, you're going to need to buy server, storage, networking, backups, you're going to need to pay your personnel, et cetera. And these upfront costs can be really challenging for a new company or a division, but the benefit with a capital expense, it is a predictable fixed cost. You know every five to eight years, you're going to be spending money on servers, et cetera. But we also know that the value of those assets are going to decrease over time. And one of the biggest issues we see with CapEx is that we have so many wasted resources. For example, if you've been working on a project when that project is over, those resources are just sitting there losing money and collecting dust. On the other side of that coin, we have OpEx or operational expenditures. These are ongoing billing costs. Using the OpEx model, we pay for the product or service as we use it. For example, we pay for Office 365 or Azure Services or maybe it's a Google account, et cetera. One of the best advantages of moving to an OpEx model is the ability to test before committing, such as do you want to test a server application? Do you want to test a new program? You can do all that without the upfront cost of buying all the equipment. The OpEx model is fantastic for agile environments where demand is unpredictable. Unpredictable environments include seasonal businesses or an environment that maybe spikes once a year when there's a really big sports event, and for those five or six hours, you're at capacity, but the rest of the year, you're below capacity. And the operational expense model lets us delete a resource when a task is done. For example, maybe you were testing out a new piece of software. When you're finished and you've proven that it does or does not work, you can easily delete the resource and that is it. You have not wasted money provisioning for hardware that's just going to sit there. And finally, you should be familiar with the term, the consumption-based model, and this is the model that is used by cloud service providers. It allows us to only pay for what is used. There are no upfront costs, and we can stop paying for the services that are no longer required. Having a firm understanding of the benefits and considerations of moving to cloud services will help you pass the Azure exam. And if you're not taking the exam, this will provide you a solid foundation of the terms used when referring to cloud services.