What is the difference between a private cloud and a public cloud?

The metaphor of cloud storage may be a bit exaggerated, but we can still feel the vague concepts associated with the cloud, and the future of this technology is full of unknowns, as is the case with private cloud storage as we know it. While private cloud stores on the market claim to benefit from the addition of firewalls to the existing public cloud, there are indications that private cloud storage has fallen to public storage.

Speaking of public storage, it is difficult not to associate with the selective outsourcing of the post-network company era, but nonetheless, it is simple and inherently available. The name of the public store does not sound proprietary, much like putting things directly in there without being managed in an orderly fashion. And to be honest, the word "public" doesn't sound as cool as "cloud".

What is the difference between a private cloud and a public cloud?

The name change does not change its nature, it is still a storage architecture technology that provides a better service. What we have to admit is that regardless of which brand of product is selected, the enterprise will benefit from the private cloud architecture chosen. In a sense, the emergence of the private cloud market is the result of the development of the public cloud. One we have to admit is that storage is an irreplaceable part of a cloud solution, whether it's a public cloud or a private cloud. In particular, for server virtualization, cloud computing can be applied. Nevertheless, a mature storage strategy is essential to ensure a successful deployment of the cloud.

Compared to the advantages of public cloud storage, we find that private cloud storage has some of the following features:

• availability. When the user needs, space needs can be distributed in a timely manner, and require the timely recovery after use.

• Quality of service. Detailed service level descriptions are required and strictly referenced. Measurable metrics can be used to define how well the response time, recovery time, and activity time are supported by the user.

• Cost fixing. In a cloud environment, the charge is usually based on storage per unit. The user simply pays for the portion of the actual use based on the service level agreement, rather than on the allocated space or a certain standard.

When you look at the cloud storage price list, you tend to see some tempting concessions, but who really benefits from it? There is a clear distinction between public and private clouds. In the public cloud architecture, users and organizations that sign agreements will benefit. For the user, they will have all the support of the application, for the organization, the cost is relatively fixed, perhaps compared to the maintenance of a system is cheaper. The IT department needs to tell the cloud service provider that the platform is the precise definition of the service. Although the cost of the business unit is relatively fixed, the public cloud also has a "how much to buy" refund advantage, and there are specific service level agreements, and unfortunately, these standards do not adapt to the IT department. Users need to get enough storage space and start to manage it, monitor the system and start detailed costing.

Also, it should be noted that these benefits do not mention "using the most advanced storage arrays", "Fastest disk" or "10Gb Ethernet." In fact, there are no relevant technical guidelines. The public cloud focuses on better operations: service levels, cost control, and fast response capabilities. Storage vendors, however, tend not to focus on operational issues, they are simply selling hardware and software. So what do these vendors sell for the private cloud? To be sure, it's definitely not just a hardware upgrade and a fantasy. Fortunately, this has been confirmed. As long as the private cloud can be applied to the correct environment and configuration, it will never be just a hardware concept.

When it comes to cloud architecture, some vendors emphasize scalability and flexibility requirements. It is certain that the relatively low cost cloud architecture model will be more attractive. But almost every vendor will claim that they have such attributes, so these definitions are less useful. In addition, cloud deployment refers not only to the hardware architecture, as the cloud develops to the end and the process is more meaningful than the product itself.

Cloud architecture requires mature processes

Many IT consultants have developed their own business process maturity models, but almost all look alike and search engines can quickly find them. Basically they are all around the following five aspects of maturity in consideration:

• Level 1. In particular, at least part of the process should be deliberately defined clearly or with relevant reference documentation.

• Level 2. Sustainability, well-defined processes can be all different even when used in different functional areas.

• Level 3. Processes are not only well defined and extended to the entire organization, they are linked to performance reviews.

• Level 4. Periodically analyze the process to measure the results. Correlate results with business operations and inform shareholders.

• Level 5. Continuously develop new business processes based on quantitative feedback results.

In the concept of private cloud storage, the maturity of organizational processes has been clearly defined as one of the prerequisites for successful deployment of a private cloud. Before considering implementing private cloud storage, the enterprise must reach at least the third level. The need for a standard process is because it concerns the standardization of the architecture, which we will discuss in detail below. If the enterprise has not yet reached the third level of maturity, the first step needs to improve the maturity, and then consider the start of private cloud deployment.

Build a private cloud storage architecture

What the enterprise can gain from the cloud architecture depends on the standards and characteristics of the cloud architecture itself. This includes good controllability, optimized usage, streamlined infrastructure, and enterprise-class management practices.

A central feature of private cloud storage is a standard architecture, sometimes referred to as a Reference architecture. Some people may disagree with the view that, since it is a standardized framework, there should be a standardized process, and in this sense it makes sense. However, whether it is backup recovery, space pre-allocation, or monitoring or other storage-management-related operational processes can be standardized processes on different platforms.

Although the Reference architecture can be a manufacturer, the situation is often made up of several vendors. The Reference Architecture actually refers to the different systems and configuration specifications that the enterprise can support. This includes the software and firmware version number to determine the consistency of the enterprise's use of the product. For most businesses, storage consolidation tends to play an important role in drawing closer to the reference architecture. Because of business mergers, business unit independence, or just environmental issues, companies often have to forgo cost and technical considerations to select a range of systems and platforms. The emergence of private cloud storage is a good opportunity to start cutting unrelated systems out of the data center, even if it is not possible at the moment, but at least it can stop it from developing to other aspects.

Private Cloud building Blocks

This means that they can use pre-configured systems, such as NetApp's flexpod, when it can build a reference architecture for any combination of systems. Flexpod is a pre-configured system consisting of VMware components, Cisco Unified Computing Blade servers, Nexus switch components, and the FAS storage of NetApp itself. This may be a good choice for many organizations that want to deploy a new system or software or hardware update because it is a completely new system and does not incorporate other vendors ' storage. It has also become relatively easy for technical support because three of vendors have coordinated configurations and firmware versions.

(Editor: Lu Guang)