What is scalability in cloud computing?

This blog has been expertly reviewed by Jason Oliver, Technical Practice Lead and AWS Ambassador at Nasstar. 

The golden rule of computing is that demand never remains the same. Different workloads require varying resources, while peaks and troughs in user requirements make under and overprovisioning a concern. The 2023 State of the Cloud report showed that 82% of decision-makers considered optimising cloud spending as their biggest challenge. This led the rankings ahead of things like cloud security and migration challenges.  

But achieving this consistent performance along with cost-effectiveness is a delicate balancing act. Scalability in cloud computing provides an effective solution. 

Jason Oliver, Technical Practice Lead and AWS Ambassador at Nasstar, said: "Scalability in cloud computing is the indispensable bridge between high performance IT systems and the paramount pursuit of ensuring a return on investment (ROI) in cloud services spending, a concern at the forefront of every business today." 

This shift in mindset — from deploying new services to optimising existing environments — makes scalability essential in modern cloud environments. In this blog, we’ll look at the types of scalability in cloud computing, the benefits, and how you can get started. 

How cloud computing works 

Cloud computing refers to the delivery of computing services over the Internet. IT resources used in cloud computing include the following: 

• Central processing unit (CPU) processing power 
• Data storage capacity 
• Virtual machines (VMs) 
• Security 
• Automation 
• Big Data and Analytics 
• Networking  
• Load balancing and edge computing services 
• Internet of things (IoT) services 
• Artificial intelligence (AI)/ Machine learning (ML) services 
  

Cloud computing enables on-demand access to this shared pool of computing resources. It is much easier to deploy and maintain compared to on-premise computing power, with benefits such as cost efficiency, flexibility, and scale.  

There are three primary types of cloud services.  

1. Infrastructure as a Service (IaaS) provides the fundamental building blocks of computing, like servers and storage, for clients to build their own environments. 
2. Platform as a Service (PaaS) provides the tools for developing and managing applications, perfect for development teams 
3. Software as a Service (SaaS) provides ready-to-use self-service applications with little configuration needed, and where data typically resides alongside the application. 
   

In the modern world of remote working, increased workloads, and high availability, cloud computing brings several significant advantages. Chief among them is scalability. 

What is cloud scalability? 

Cloud scalability refers to a cloud system expanding based on business needs. This usually happens automatically within the cloud environment. Being able to scale is a key advantage of cloud computing, with resources seamlessly adjusting when faced with different conditions. 

Prominent public cloud providers, such as Amazon Web Services (AWS) and Microsoft Azure, allow auto-scaling by using policies and intelligent monitoring. These can dynamically allocate resources, providing businesses with the flexibility to scale up or down based on needs, meeting demand in the most cost-effective manner. 

The nature of cloud infrastructure is crucial in enabling this scalability. High-quality, well-designed scalable architecture can accommodate significant load changes easily. It can also ensure a consistently good user experience no matter the current resource demand. 

Cloud scalability vs cloud elasticity 

It's important to differentiate between cloud scalability and cloud elasticity. While they are similar, there is a key difference.  

Cloud elasticity means rapidly adjusting resources in real-time to meet fluctuating demand. This is often done automatically. Meanwhile, cloud scalability is the system's capacity to handle scale in a broad sense — often considering business factors like cost-effectiveness, response times and long-term performance goals. 

The types of cloud scalability 

Cloud computing combines a massive number of computing resources, service providers and cloud architecture strategies. For this reason, there are many ways to approach system design. Cloud scalability is no different.  

There are three major types of scalability, each offering unique benefits and downsides: horizontal scaling, vertical scaling, and diagonal scaling. Understanding the types of cloud scalability lets businesses choose the best strategy for their specific needs, based on aspects like efficient use of resources, cost savings and latency needs. 

Horizontal scaling 

Also known as 'scaling out', horizontal scaling involves adding more resources — or nodes — to existing infrastructure. This type of scaling expands the system's workload capacity temporarily. The horizontal approach is best for applications that need to process substantial amounts of requests at the same time while maintaining performance levels. However, it can bring complexities in data management if it’s not managed well. 

Vertical scaling 

Also known as 'scaling up', vertical scaling means upgrading the capacity of an existing server or resource. You might add more CPUs, memory, or storage, for example. Vertical scaling is simpler to implement but is limited to the maximum available capacity of individual resources. It can also involve higher costs and likely downtime during upgrades. 

What are the benefits of cloud scalability? 

Using a scalable cloud environment can bring huge benefits to different workloads: 

• Cost-efficiency: With cloud scalability, businesses can use more predictable cost modelling. In so doing, you can effectively manage and allocate resources to save on unnecessary expenditures. It also allows for a precise evaluation of ROI on your IT spending. Not using scalability can lead to inflated costs due to overprovisioning, or performance issues from under-provisioning. 
• Ease of operation: Thanks to technological advances and monitoring software, you can quickly implement scalability. IT admins often have the choice of adjusting resource capacity easily. By the nature of the cloud, this avoids the time and effort spent managing physical hardware. 
• Speed of provisioning: Unlike traditional on-premise hardware that can take a long time to upgrade, cloud scalability allows for swift configuration changes. These can be based on short or long-term business demands, letting companies roll out services in an agile way. 
• Flexibility: Cloud scalability lets you seamlessly adapt to changing business needs. Likewise, you can react to changing customer demands. With the ability to scale resources up or down, organisations can efficiently manage peak demand periods. This ensures consistent performance, high availability, lower costs and carbon emissions, and customer satisfaction. 
• Business continuity: Business continuity is critical to profitability. Compared to using on-premise hardware, scalable cloud services ensure minimal disruption to business operations. This also makes disaster recovery (DR) much more straightforward. With redundant resources spread across public and hybrid cloud data centre services, businesses can ensure continuity, recover lost data and maintain uptime. 
• Business transformation: Cloud services offer unparalleled scalability which makes them ideal for startups, SMEs, and growing companies. With flexible resources, organisations can scale up as they grow, without large upfront investments. 

"Cloud scalability empowers businesses to stay agile, efficiently manage resources, and respond seamlessly to fluctuating demands, all while maintaining cost-effectiveness and high performance," says Jason Oliver. 

How to choose the right scalable cloud services for your business 

When provisioning scalable cloud services, there are several factors that can help make the project successful: 

• Understand your business needs: First, identify your specific scalability needs. You can do this by analysing business requirements, application demands and potential growth needs.  
• Compare cloud providers: Then, choose a cloud services provider that aligns with these parameters. Assess different companies based on their scalability options, performance, reliability, and security measures. 
• Have a long-term plan: Create a roadmap for your transition to a scalable cloud infrastructure. This includes setting measurable objectives to judge the project’s success. It’s also essential to have timelines and clearly defined responsibilities within your team. 
• Use established best practices: Use best practices like phased deployment, monitoring of cloud resources and proactive planning. This will not only keep you on track, but also identify where you could make improvements in future. 
• Beware of common mistakes: Be aware of under or over-provisioning resources to help avoid overspending or poor performance. Likewise, don’t ignore key factors like security when designing your scalable system. 

What is the future of cloud scalability? 

Scalability is set to play an even more crucial role in the future of cloud computing. Emerging technologies like AI, the Internet of Things (IoT), and blockchain could influence and enhance cloud scalability. Companies will also need more scalable systems to run these demanding workloads. 

Fortunately, AI and machine learning will continue to help optimise resource allocation. Over time, this will make scalability even more efficient and predictive, helping businesses plan their systems with even greater precision.  

How Nasstar can help 

Scalable cloud computing offers a cost-effective and flexible way for businesses to deploy IT resources. It lets you react to changing needs by scaling cloud resources up or down as business needs change. 

While more companies than ever are migrating to the cloud, many aren’t making the most of their resources. At Nasstar, we’ve helped many clients embrace scalability as part of their cloud optimisation journey.  

Speak to a specialist to learn more about getting ROI for your cloud solutions. 

Frequently Asked Questions (FAQs) 

How is scalability achieved in cloud computing? 

Scalability in cloud computing is achieved with the on-demand allocation and deallocation of resources. Cloud providers use monitoring and policies to adjust resources according to preset needs. Cloud architecture is highly flexible, and businesses have options for horizontal, vertical, and diagonal scaling methods. These ensure scalability in response to fluctuating demands. 

What are elasticity and scalability in cloud computing? 

Elasticity and scalability in cloud computing are similar concepts. They both address resource allocation needs but in different ways. Elasticity involves automatic, real-time adjustments to meet changing short-term demands. Scalability is the broader, long-term capacity to expand or contract resource allocation based on user settings. Both ensure efficient performance and cost-effectiveness. 

What is an example of scalability in cloud computing? 

An example of scalability in cloud computing is a website anticipating higher seasonal demand. The site's cloud provider can auto-scale resources, adding more servers through horizontal scaling or enhancing the capacity of existing servers with vertical scaling. Both help ensure high performance during the period of higher demand.