Public cloud refers to a cloud computing model in which computing resources—such as servers, storage, and applications—are provided by a third-party vendor and shared across multiple customers via the internet. Public cloud providers own and manage the infrastructure, while customers access resources on demand through a pay-as-you-go model.

Public cloud is widely adopted for its scalability, flexibility, and cost-efficiency. It enables organizations to deploy applications and services without investing in or maintaining physical infrastructure, making it a cornerstone of modern IT and digital transformation strategies.

What is public cloud?

The public cloud model allows organizations to use a shared pool of computing resources that are hosted and operated by external service providers such as Amazon Web Services (AWS), Microsoft Azure, Google Cloud Platform (GCP), and others. These providers deliver infrastructure, platform, and software services over the internet using a multi-tenant architecture.

Key features of public cloud include:

  • Elastic scalability: Resources can be scaled up or down dynamically based on workload demand
  • Usage-based pricing: Customers pay only for what they use, avoiding upfront capital expenditures
  • Self-service provisioning: Users can deploy and manage workloads via web portals, APIs, or automation tools
  • Global availability: Data centers located around the world enable low-latency access and disaster recovery options
  • Managed services: Providers offer built-in tools for storage, networking, databases, machine learning, monitoring, and security

Public cloud services are generally categorized into three models:

  • Infrastructure as a Service (IaaS): Virtualized computing resources such as VMs, block storage, and load balancers
  • Platform as a Service (PaaS): Application development environments with managed runtimes and services
  • Software as a Service (SaaS): Fully managed software applications delivered through a browser

Why public cloud matters

The public cloud has revolutionized how organizations consume technology. Instead of building and managing data centers, companies can leverage mature, secure, and scalable infrastructure as a utility. This unlocks numerous business and operational benefits, including:

  • Accelerated time to market for applications and digital services
  • Lower total cost of ownership (TCO) by reducing capital investment
  • Increased innovation through access to advanced analytics, AI, and DevOps tooling
  • Better agility to respond to customer demands, scale workloads, or enter new markets
  • Global infrastructure with redundancy and high availability built in

Public cloud is also critical for startups and small businesses, providing enterprise-grade infrastructure at a fraction of the cost and complexity.

Public cloud vs. private cloud

While public and private clouds offer similar technical capabilities, they differ significantly in deployment model, cost, and control:

Public cloud

  • Infrastructure is shared among multiple tenants
  • Managed entirely by a third-party provider
  • Highly scalable and cost-efficient
  • Limited customization at the hardware and hypervisor level

Private cloud

  • Dedicated infrastructure for one organization
  • Hosted on-premises or by a private vendor
  • More control over security, compliance, and performance
  • Higher cost and operational complexity

Many organizations choose a hybrid cloud or multi-cloud strategy that combines the scalability of public cloud with the control of private infrastructure.

Common use cases for public cloud

Public cloud is ideal for a wide variety of workloads and industries. Common use cases include:

  • Web and mobile applications: Hosting scalable, globally distributed applications with automatic scaling and content delivery
  • Development and testing: Provisioning development environments on demand for DevOps and CI/CD pipelines
  • Big data and analytics: Using cloud-native data lakes, warehouses, and machine learning services to process large volumes of data
  • Disaster recovery and backup: Storing backups and setting up recovery environments in secondary regions without maintaining physical infrastructure
  • SaaS delivery: Deploying applications that are consumed by users over the internet, such as CRM, productivity, or ERP tools

Public cloud is especially useful for organizations that require flexibility, rapid deployment, and elastic capacity.

Security in public cloud

Security in the public cloud follows a shared responsibility model:

  • The cloud provider is responsible for securing the infrastructure (e.g., physical hosts, networking, and hardware)
  • The customer is responsible for securing the configurations, identities, data, and applications they deploy on that infrastructure

Key security considerations in public cloud environments include:

  • Identity and access management (IAM): Controlling who can access cloud resources and what actions they can perform
  • Data encryption: Ensuring data is encrypted in transit and at rest using customer-managed or provider-managed keys
  • Network security: Using firewalls, private networks, and access control lists to restrict traffic
  • Vulnerability management: Identifying and addressing misconfigurations or unpatched software across workloads
  • Monitoring and observability: Tracking user behavior, API calls, and infrastructure changes for signs of compromise

Security in the public cloud requires continuous visibility and automated enforcement of best practices to reduce risk and maintain compliance.

Challenges of public cloud

While public cloud offers numerous advantages, it also introduces challenges:

  • Cost visibility and control: Without proper governance, usage can grow rapidly and unpredictably
  • Security misconfigurations: Human error or lack of visibility can expose resources or sensitive data
  • Vendor lock-in: Using provider-specific services may create migration complexity or limit portability
  • Compliance: Ensuring regulatory requirements are met across regions and workloads can be complex
  • Shadow IT: Teams may deploy services outside of central governance, creating risk and inefficiency

Organizations need strong cloud governance frameworks, access controls, and observability to effectively manage public cloud environments.

How Orca Security helps

The Orca Cloud Security Platform delivers agentless-first, unified cloud-native security for public cloud environments across AWS, Azure, Google Cloud, Oracle Cloud, Alibaba Cloud, and Kubernetes.

With Orca, security teams can:

  • Continuously scan and monitor their entire cloud estate for all types of cloud risks
  • Analyze risks holistically, contextually, and dynamically to identify those most critical
  • Prioritize remediation and leverage AI-driven capabilities to address issues faster and more easily 
  • Prevent risks from reaching production environments with comprehensive application security capabilities integrated with runtime security
  • Secure sensitive workloads with lightweight real-time runtime security for advanced Cloud Detection and Response (CDR)
  • Achieve and sustain multi-cloud compliance with an extensive library of built-in and customizable regulatory frameworks and industry standards

Orca enables organizations to secure their public cloud across the entire application lifecycle.