A public cloud is a platform that makes standard cloud computing resources (such as storage, compute, development environments, applications, virtual machines, and so on) available via the internet to anyone who wants to use them. Using the public cloud, some organizations can eliminate the need for an on-premises data center that can sometimes be expensive to maintain and manage. Other organizations combine public and/or private clouds with on-premises computing for a multicloud or hybrid model.
Offered on demand, the public cloud allows users to choose their delivery model: infrastructure as a service (IaaS), platform as a service (PaaS), or software as a service (SaaS). Users typically pay for public cloud services through a monthly subscription or a pay-per-use fee. Cloud service providers are responsible for managing and maintaining the entire system.
Today, there are three main public cloud providers: Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform. These providers deliver their services over the internet or through dedicated connections, and they use a fundamental pay-per-use approach.
How does the public cloud work?
Data centers are critical components of the public cloud. The difference is that the cloud service providers own, operate, and manage those data centers – not individual organizations that use public cloud services. Other primary components include networking, storage, and virtualization.
Public cloud data centers can contain thousands to hundreds of thousands of virtual machines in a multitenant environment, meaning that they can be shared by public cloud users. These provide a virtualized environment that allows organizations to scale their IT infrastructure near infinitely as needed, hosting certain workloads or applications on the public cloud provider’s virtual infrastructure located somewhere outside the organization’s physical offices.
Organizations pay to use or rent those machines and other cloud services that might include data storage, app development and deployment tools, and software applications. With the public cloud, an organization can have very quick access to as many computing resources as they need at any moment without having to invest in on-prem infrastructure, expanding and shrinking capacity as requirements ebb and flow. Scaling is done very simply by the organization’s IT personnel, using a self-service interface.
Thanks to the highly scalable nature of the public cloud, organizations can keep multiple copies of their data in different virtual locations as desired. This can increase resiliency and reduce downtime if data from one source is corrupted. It can also aid disaster recovery.
What are the benefits of a public cloud?
Lower operation costs, thanks to elimination of the need to invest in on-premises IT infrastructure
Massive scalability to grow and expand as your business grows
Quick, simple, and on-demand upgrades and minimum effort to operate and manage certain services - the cloud services provider installs, operates, maintains, and monitors the hardware and software to deliver most services
Secure underlying infrastructure to protect your data from threats
More reliable and redundant model than on-prem data centers because outages or infrastructure issues won’t prevent you from accessing your always-available data
What are the differences between private cloud, public cloud, and hybrid cloud?
The public cloud is hosted by one of the three big cloud providers (AWS, Microsoft, Google) and delivers IT resources and services (IaaS, PaaS, SaaS) over the internet to the public cloud. Customers pay in increments based on the resources they consume.
A private cloud offers many of the same capabilities as a public cloud, but it is owned and maintained by a single organization. The company could host the private cloud in its own data center or outsource the hosting and operations to a third-party provider.
A hybrid cloud combines the elements of the public and private cloud, and it’s intended to allow customers to decide where they want to host their workloads based on what makes most sense for their organization. For instance, some organizations keep highly sensitive or confidential data and workloads in private clouds and use the public cloud for less-sensitive data and applications.
Is the public cloud secure?
Companies sometimes choose not to use the public cloud because of security concerns around where their data or workloads are stored on the internet. However, this worry over public cloud security can easily be alleviated when organizations look into the high level of security measures public cloud providers offer and their hefty investments in the most up-to-date security solutions. Because they have myriad customers dependent on the security of their services, public cloud providers are likely some of the most security-conscious organizations out there. The level of talent they hire and the tools they develop and use to protect their customers’ data are typically of the utmost quality and probably unsurpassed by other organizations.
Public cloud use cases
Some typical use cases for the public cloud include:
Disaster recovery and business continuity - Providing redundant on-prem systems can require a lot of money and in-house effort. In the public cloud, an organization has the safety net of a second infrastructure with copies of all of its critical data and applications, which can be activated in the event of a power failure or on-prem system malfunction.
Dynamic resource requirement needs - Using a public cloud allows you to scale resources and achieve levels of performance as needed based on seasonality or demand peaks from the business. When services are elastic and can be easily expanded, you only pay for the capacities actually used and, compared with an oversized in-house IT infrastructure, can significantly reduce your costs.
Data security - The rise of cyberattacks in recent years has increased the need for organizations to consider hosting their workloads in ultra-secure locations. When you store your data in the public cloud, you can delete or move any sensitive data into another account remotely. Breaching security protocols in the public cloud is typically very difficult.
Public cloud challenges
Many companies have come a long way in their cloud journeys, taking advantage of the flexibility, scalability, and usability that cloud services offer. But some challenges still remain:
Difficult migrations: Workload migration to the public cloud goes beyond "lift and shift." Challenges exist with interoperability, data and application portability, data integrity and security, and more.
Benefits only available to cloud-native applications: Some of the benefits of the public cloud only apply to cloud-native applications, not traditional apps that have been moved to the cloud. But rebuilding applications to be cloud-native can be expensive and time-consuming.
Application performance: If data used by an application isn’t stored in the same location as the application, latency issues can occur – which can be a serious challenge when it comes to mission-critical applications.
Compliance and regulatory concerns: Companies may be restricted from storing data on the cloud service provider’s remote environment due to data security and privacy regulations, especially in places such as the European Union where data privacy is closely guarded.
Loss of control over data: The ease of adopting public cloud services can lead to shadow IT, which means that applications might be provisioned away from the traditional purview of IT visibility so admins can’t easily monitor or manage them.
Shared responsibility: Additional work is required to ensure proper governance and cybersecurity measures when it comes to the public cloud. Shared responsibility means both parties (your organization and the cloud service provider) have some responsibility in maintaining security of data and applications.
Cost overruns and egress charges: Operational expenses can become unjustifiably high as egress and other fees quickly add up. It’s not always easy to predict monthly costs in the public cloud.
Vendor lock-in: When you choose a cloud service provider, you can sometimes be locking your organization into their ecosystem of APIs and services. Developing cloud-native applications for multiple cloud providers can be costly, but developing apps for just one provider makes it difficult to migrate to another provider in the future.
Continued fragmentation of IT: Public clouds require distinct operations and expertise to manage their services, which can result in adding yet another IT silo rather than eliminating one.
As organizations grapple with the challenges of public cloud services, many are starting to rethink their strategies. In fact, according to IDG research, 71% of survey respondents are planning to move all or some of their workloads from the cloud back to private IT environments in the next two years, suggesting that public clouds are not ideally suited for all enterprise use cases.
But what if you could have the best of both worlds – the flexibility and scalability of the public cloud with the security, control, and performance of an on-premises data center? That’s where Nutanix comes in.
How Nutanix can help
The Nutanix Cloud Platform allows you to run workloads and applications across on-premises data centers, public and private clouds, multiple hypervisors, and containers as a single cohesive infrastructure. Enabling a hybrid multicloud model with Nutanix gives you the flexibility to pick the right resources for your workloads and adjust and scale them seamlessly as your business grows. Burst capacity from data centers to hosted and public clouds like AWS or Microsoft Azure.
Unlike other hybrid cloud offerings available today, the Nutanix hybrid multicloud solution features out-of-the-box networking integration with public clouds. This allows your DevOps team to focus on code and application design, not the infrastructure or cloud connectivity. Nutanix Cloud Platform offers the best of all worlds with robust management and control on a single pane of glass – which unifies management and operations with one-click simplicity, intelligent automation, and always-on availability.