Cloud computing is a model of delivering computing resources over the internet, enabling on-demand access to a shared pool of computing resources. In recent years, it has become massively popularised, allowing users greater flexibility, scalability and cost savings in computing resources.
There are three foundational cloud computing models available for organisational use: public cloud, private cloud, and hybrid cloud.
With each presenting unique advantages and disadvantages, it’s good to understand which cloud model type would best complement your business operations while minimising security risks.
This blog will help you understand the differences between these models, providing expert insight for choosing a cloud solution that is most secure and well-suited to your business. We’ll also provide tips on how to keep your cloud environment secure with cloud penetration testing.
What is a Cloud Environment?
A cloud environment refers to the infrastructure and services delivered by cloud providers. These environments can be:
- Public cloud: Shared infrastructure operated by providers such as AWS, Microsoft Azure, or Google Cloud. These clouds offer significant scalability and cost-efficiency.
- Private cloud: Dedicated to a single organisation, providing greater control over security, compliance, and data governance.
- Hybrid cloud: A combination of public and private environments, enabling flexible workload distribution.
Understanding the Role of Cloud Service Providers
As discussed above, cloud environments are provided by cloud service providers. The main ones include Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform. These three major providers offer a range of cloud services, from infrastructure to platform and software as a service (SaaS).
A cloud service provider will manage infrastructure within your cloud environments, ensuring that the security and performance of your operating systems are healthy.
Industry giants like AWS and Azure offer a range of service options and extensive cloud infrastructure: something private organisations lack the scale and reach to replicate. However, when it comes to dedicated and customised services, private cloud service providers maintain the upper hand, able to provide services tailored to specific needs.
Which Cloud Computing Model is Most Secure?
The short answer: private cloud models generally offer the highest level of security because they are private to your business, but the reality is more nuanced than that.
| Cloud Type | Security Characteristics | Key Considerations |
|---|---|---|
| Private Cloud | Dedicated infrastructure, full control over security, customisable compliance measures | Requires in-house security expertise and resources; security depends on internal implementation |
| Public Cloud | Robust provider-managed security (encryption, threat detection, certifications), shared infrastructure | Security largely depends on proper configuration and user practices; shared responsibility model |
| Hybrid Cloud | Flexibility to balance security and scalability, combining benefits of both models | Added complexity; potential vulnerabilities at integration points between environments |
Private clouds offer strong security advantages by dedicating infrastructure to a single organisation, allowing full control over security, data residency, and compliance. This minimises risks of data leakage and enables customised security measures, essential for sensitive data and strict regulations.
Public clouds, shared among multiple users, are secured by providers with encryption, threat detection, and certifications. The main risk lies in how well organisations manage their security settings, and whether public cloud services are being used correctly by your team members.
Hybrid cloud solutions provide flexibility but add complexity, with potential vulnerabilities at integration points between public and private clouds.
The key point? Any cloud can be secure if managed proactively, with effective security systems in place.
Cloud Infrastructure: How to Stay Secure
Cloud security is a critical aspect of cloud computing, as it involves protecting sensitive data and applications from unauthorised access and security threats.
A lot of cloud security rides on the cloud infrastructure itself: the underlying hardware and software components that support cloud services, including servers, storage, and networking.
Public cloud providers will take steps to implement robust security measures for users, including encryption, firewalls, and access controls, to ensure the security of customer data. Providers are held to rigorous standards to ensure the best security possible; however, it is also up to users to follow best practices to ensure public cloud services are safely used.
Private cloud infrastructure, on the other hand, depends on the deployment model and physical infrastructure ownership. This means that it’s up to organisations to secure their own infrastructure.
While private cloud infrastructure is generally considered more secure, again, it is fundamentally up to your organisation to make sure that the correct security measures are in place to evaluate your private cloud’s resilience to threats. Businesses must also take into account strict regulatory compliance standards and conduct security and compliance evaluations based on this.
Access Management and Cloud Storage
Access management is critical in cloud computing, as it involves controlling who can access cloud resources and data. Cloud storage solutions, such as object storage and block storage, provide scalable and durable storage for cloud-based applications and data.
Public cloud resources offer a range of access management and cloud storage services, including identity and access management (IAM) and storage gateways.
Private cloud environments require organisations to implement their own access management and cloud storage solutions, ensuring greater control and security.
Why Cloud Penetration Testing Matters
Cloud penetration testing goes beyond checking compliance boxes; it actively validates whether your security controls work as intended.
For hybrid cloud environments in particular, pentesting helps identify vulnerabilities that arise from the complexity of integrating public and private infrastructure, such as insecure APIs, weak authentication mechanisms, or data leakage between environments.
Regular penetration testing provides several critical benefits:
- Real-world risk assessment: Pentesters think like attackers, identifying exploitation paths that automated tools might miss, such as chained vulnerabilities or business logic flaws specific to your cloud architecture.
- Configuration validation: Cloud environments are dynamic, with infrastructure frequently changing through automation and DevOps practices. Penetration testing validates that security configurations remain effective amid constant change, catching misconfigurations in IAM policies, network segmentation, or encryption settings.
- Compliance assurance: Many regulatory frameworks, including PCI DSS and GDPR, require regular security testing. Penetration testing demonstrates due diligence and helps organisations meet these compliance obligations while actually improving security posture.
- Incident response preparation: Penetration testing exercises reveal how well your monitoring and incident response capabilities detect and respond to attacks, providing valuable insights for improving your security operations.
For organisations operating hybrid cloud environments, penetration testing should take into account all components: public cloud services, private infrastructure, and the integration points between them.
This well-rounded approach ensures that security vulnerabilities don’t emerge from where different cloud models connect in your organisation.
The Bottom Line: Cloud Security is About Strategy, Not Just Infrastructure
Private clouds may offer built-in advantages through dedicated infrastructure and full control, but they aren’t automatically the most secure option. Public and hybrid clouds can be equally secure when backed by strong governance, correct configurations, continuous monitoring, and regular penetration testing.
A well-managed public cloud can outperform a poorly secured private cloud, and the same applies across all models. What matters most is a proactive, strategic approach to cloud security.
Ready to strengthen your cloud security? Find out more about our cloud penetration testing services today.
