Cloud Computing is very much in vogue with multiple providers of such services in the market. The Cloud provides an opportunity for Enterprise resources to be moved to the cloud. Enterprise IT departments today mostly manage applications across a maze of machines as part of a complex IT framework. Part of the network could be within their premise and the rest could be external. CIOs need to assess their unique IT mix from time to time to evaluate the composition of on-premises, private cloud and public cloud infrastructure. With evolving business goals, it is but natural that the composition of these would change from time to time. However, this is not an easy job. At a time, a number of applications, could be in tens or in hundreds are to be evaluated for migration and it requires deep knowledge and expertise to determine the local infrastructure as well as the Cloud Infrastructure where they have to be moved to.
In order to determine where your enterprise data or application should move – private, public or hybrid clouds, you would require a careful understanding of these infrastructures and determine for yourself what needs to be moved to where in the Cloud.
Public Cloud
Services of a public cloud can be provided off-site over the internet. These clouds offer a great level of efficacy in shared pool of resources, but they are also more vulnerable than private clouds. A Public Cloud is useful when:
- The workload of your applications is used by a lot of people like the email applications.
- You require long term storage including tape storage, or data storage of any kind where your local physical media fails repeatedly.
- You require a testing site for the development of code. You could perform load testing easily by increasing demand and decreasing it later on a public cloud.
- You have SaaS provided by a third party who has implemented a Security Policy.
- You require to increment your capacity during peak demand or seasonal demands.
- You are collaborating with other parties in an operation or project.
- You are involved in a Temporary Software project with a Platform as a Service (PaaS) on cloud.
Public Cloud scores over other clouds in the areas of Scalability and Cost. Since there is no need for on premise infrastructure, Public Cloud works on a Pay-As-You-Go Model and therefore costs less.
However, there are a few concerns that IT departments have regarding Security of Public Clouds in general. It is important for you to study the security approaches that the Service Provider puts in place. The other concern is that of reliability. How can a Public cloud be more reliable when it caters to multiple customers? Moreover, this would depend on Service Provider Availability of the Cloud.
Study in detail the commitment that the Service Provider extends to you. The Performance of a Public Cloud which is a shared resource is expected to be lower than a Private or Hybrid Cloud.
Private Cloud
Though there are a number of advantages of a Public Cloud, enterprises rarely deploy all their applications on the Public Cloud. It is easier often to move the on premise applications to a Private Cloud rather than a Public Cloud. A Private Cloud offers dedicated network infrastructure for you, whether it is an on premise dedicated infrastructure or an external dedicated infrastructure from a third party.
A Private Cloud is usually deployed for the following scenarios:
- Control and Security of your data is paramount and you do not want the information to be leaked out.
- Your business is part of and abides by strict security and data privacy issues of an industry.
- Your company is large enough to run a next generation cloud data center of its own.
- Your applications have a few legacy bindings which prevent them from working properly on public clouds.
- The application has predictable usage patterns and low storage costs.
- The application is poorly written and not used frequently, it does not make sense to migrate to a public cloud.
- You are not comfortable to migrate to a public cloud, as your engineering team does not have the capability to migrate.
- You want a very reliable and dedicated network with very high availability.
- You have sufficient budget to maintain a Private Cloud Infrastructure.
The limitation for a Private Cloud is scalability. It may be constrained to handle peak demands from users, as the infrastructure is not extensible as in case of Public Clouds.
Hybrid Cloud
A Hybrid Cloud is a combination of Private and Public options and is planned to get the best of both the worlds. You can keep your business requirements spread out over parts of a public and a private cloud, thereby attaining maximum efficiency. Here are some indicators where you would like to use Hybrid Cloud:
- Your company offered services tailored to different vertical niches. You could use the Public Cloud for interaction with the clients, while securely storing their data in a Private Cloud.
- You want to have the scalability and flexibility that public cloud offers while maintaining your key infrastructure securely in your private cloud.
An important thing to understand about Hybrid Cloud is that it is as strong as the integrations that unite its constituents.
