Private cloud vs public cloud
Thought about investing in a cloud server for your business? The thought of migrating all of your data and processes may seem daunting, particularly if you don’t know which cloud deployment to choose.
But what is a private cloud and how does it differ from a public cloud? In this post, we’ll discuss all the cloud deployment options, their advantages and disadvantages, as well as frequently asked questions about both private and public cloud solutions.
Public cloud vs private cloud
There are a few stark differences between private and public clouds, which we’ll discuss at great length below. For now, here’s a snapshot view that explains the differences between private and public clouds in a nutshell.
What is private cloud?
A private cloud is a popular cloud computing environment that gives businesses complete control over their hardware, software and security. Private clouds can be hosted on-premises, in a data centre or by a third-party provider. As the name suggests, they’re private, meaning only the business has access to their private cloud. It’s a favoured option not only due to their security but vast customisation capabilities, which is great if a business has specific requirements.
What is public cloud?
A public cloud is a cloud environment shared by multiple businesses. While this means less control over hardware and resources compared to say a private cloud, they are typically easier to use. You may already know about these public clouds already:
- Amazon Web Services (AWS)
- Microsoft Azure
- Oracle Cloud
- Google Cloud Platform (GCP)
- …and many others!
The cloud services above will use groups of data centres, which are then segmented into virtual machines for tenants to rent. Tenants may also wish to pay for additional services offered by these public cloud providers such as extra storage, software, tools and much more. Ultimately, a public cloud removes the legwork required for a business to host their own cloud on-site or within a data centre too.
What is multitenancy?
If anyone can have a space on the public cloud, that means it's shared by multiple tenants on a ‘multitenancy’ model.
Multitenancy, as the name suggests, is where multiple tenants (cloud customers) are accessing, using and storing data on the same cloud server. Even though it’s common knowledge that many users share the same public cloud, they’re not aware of each other. This is because their cloud space is entirely separate from other users.
Plus, without multitenancy, public cloud servers wouldn’t be utilised in the best way possible. Some tenants require specific things, so a public cloud may store metadata (an information file) on that particular tenant and alter how the cloud looks to them, depending on their needs.
The disadvantage of this is some companies may not be able to share sensitive information on a shared infrastructure, which is completely understandable from a data protection perspective. However, costs are fairly low on a multitenancy model, as a public cloud provider can sell cloud server space for smaller costs to tons of users.
What are the different types of public cloud?
Public cloud solutions come in different packages and formats, depending on their intended use. Below is a brief overview of what some of these public cloud solutions can look like.
SaaS
Software as a Service, or SaaS cloud, lets users connect to and use cloud-based apps over the internet on a subscription basis. The SaaS cloud provider will typically sell their solution online which users can access through dedicated login details. The SaaS public cloud model works on remote servers and is regularly maintained by the provider. Users can access them via web browsers and even mobile devices if they wish.
SaaS is widely used for many things such as customer management (CRM systems), collaboration tools, and other forms of task management. You may have come across some SaaS in your day-to-day work, such as Slack, Dropbox, Salesforce or similar.
PaaS
Platform as a Service, or PaaS cloud solutions, provide a platform for users to test, develop and deploy software and applications. In the case of a PaaS public cloud provider, they’ll supply the user with everything they need such as libraries, frameworks, debugging and databases in order for specialists to develop their applications.
But why would they need a PaaS to do this? In simple terms, a PaaS allows developers to focus on what they do best, without having to create or manage the infrastructure (which is where an IaaS comes in).
IaaS
An Infrastructure as a Service (IaaS cloud) provides users with VMs (virtual machines) to act as various elements such as storage and networking on-demand, without the need for physical hardware. The advantages here are being able to run various applications, and even operating systems, on a public cloud through the internet. Some providers may even offer add-ons such as firewalls for added security and peace of mind.
What’s a hybrid cloud?
A hybrid cloud combines the advantages of private cloud with the ease of public. By combining the scalability, agility, and cost-effectiveness of a public cloud with the security, control, and compliance of a private cloud, businesses can benefit from the best of both worlds.
This means workloads can be shifted between the private and public clouds as necessary in a hybrid cloud architecture, allowing businesses to tailor the hybrid cloud model to their needs, while also maximising their IT resources and expenses. For example, a business might use a private cloud for its most sensitive data and apps, and then a public cloud for less sensitive ones.
But is a hybrid cloud the same as a multi-cloud? Not necessarily. The two are sometimes used interchangeably, but there are some key differences between them.
What’s a multi-cloud?
Multi-cloud actually means “multiple public clouds”. This is the biggest differentiator between a multi-cloud and a hybrid cloud, as the latter uses both public and private cloud servers to operate. A business may use multiple clouds to run a business function on one cloud, and another type of function on the other. But why would businesses want to do this instead of having a tailored approach?
Essentially, a multi-cloud approach can utilise several public cloud types to cover all operations. For example, they may use multiple IaaS, SaaS or PaaS services to cover all the features they can provide.
The disadvantage of this approach is it can leave a business more vulnerable to attacks, as each system operates on a public cloud. Plus, if services in multiple clouds need to communicate, latency issues may arise – particularly if the data centres are very far apart from one another.
Despite this, a multi-cloud approach may be cheaper to run in the short term (or long term, depending on business requirements), and can be easier to run without a dedicated IT team. It can also help businesses not feel like they’re “locked in” to one type of cloud.
Advantages of private cloud
There are many obvious advantages as to why businesses may opt for a private cloud just from reading the above. For the sake of clarity, let’s go through a full list of all the advantages of using a private cloud below:
1. Security
As the name suggests, private clouds are highly secure. They’re only accessible by the business themselves and aren’t shared with other users (unless specific permissions have been granted to individual users). While no cloud server (or any server for that matter) is 100% secure, a private cloud can be reinforced with further security protocols such as a VPN to encrypt connections, log management, and backup systems should a disaster strike.
2. Customisation
Investing in a private cloud grants the business full root access. This allows relevant administrators and IT employees to add software specific to the business, regularly update apps, grant access controls and implement other relevant infrastructure.
3. Cost
A private cloud is costly to begin with, however, it can save you money in the long run. This ties in with its customisation potential. For example, you won’t have to invest in different public cloud types to handle various areas of your business. Instead, you can add the relevant infrastructure within one private cloud. Plus, private clouds usually come with a plan that’s fixed, meaning you won’t have to worry about using too many resources and having to pay extra for them.
4. Scalability
Need more resources? As your project or business grows, so can your private cloud server. Increase your resources to handle more data and traffic spikes, plus get down-to-the-minute billing for extra control too. With Fasthosts, you can configure your private cloud to the exact requirements you use. So if you need a private cloud with more RAM as opposed to SSD (and vice versa), you can tailor this to your needs, without having to compromise on a set package alone.
5. Backups and recovery
While this goes for every cloud solution, private clouds offer backup and disaster recovery features. On-premise private cloud solutions allow the business to host the cloud environment internally at their location. This is because private clouds consist of a dedicated physical infrastructure, so a business has better control over all functions, including data management.
6. Compliance
The National Cyber Security Centre provides detailed steps for how cloud servers can protect data against several principles listed. It can also help as a step towards UK GDPR compliance, particularly if you run a business with sensitive data.
7. Uptime
Private clouds can rely on an internet connection or private network. Plus, businesses can design an infrastructure that upholds uptime in the event the internet goes down. This can be in the form of implementing hardware components such as additional servers or networking equipment, power supplies, backup systems and much more.
8. Cheaper than a dedicated server
Dedicated servers vs cloud servers, just what is the difference? While we cover this in our guide, the bottom line is that a cloud server is a far more cost-efficient model. While dedicated servers have many advantages, a cloud server is both cheaper and easier to scale.
9. Performance
Private cloud can potentially offer better performance than public cloud. With private cloud, you don’t need to share space with any other businesses, giving you increased space capacity for your organisation. This can lead to improved speeds and reduced downtime.
Disadvantages of private cloud
Despite their many advantages, there are also a number of disadvantages to opting for a private cloud that need to be taken into account.
1. The start-up cost
The initial cost of a private cloud might be a tough one for businesses to get their head around. Though it may contradict our earlier statement, a private cloud may not be totally feasible if your capital is low, so it may be worth using other cloud solutions until you’re able to work towards a more bespoke cloud solution.
2. Dedicated management
If you don’t have the personnel, or knowledge to manage a private cloud, then you likely won’t use it to its full potential. Plus, if a private cloud isn’t managed or reinforced correctly, then this can result in vulnerabilities or a solution that your business can’t fully use to carry out its duties.
3. Maintenance
You’ll need dedicated IT staff with specialist knowledge to uphold the infrastructure, software patches, security and hardware management of your private cloud. While this goes back to our costs point, you’ll need to ensure you can afford IT staff to regularly maintain your private cloud, as well as additional training where required.
4. Reliability issues
A private cloud has all the potential to be the most reliable solution if configured correctly. However, it’ll only be as reliable as the package you sign up for. Will it have enough space to manage traffic flow? If there’s a power outage and you opt for an on-premises cloud, what will be in place to get it up and running again?
5. Reduced accessibility
This may be desirable if you want to restrict access to your data to internal users only, but if you want to transfer data more easily, a public cloud may not be the right choice for you. In this case, the restricted area of operations created by a private cloud infrastructure could reduce necessary accessibility.
Advantages of public cloud
Public clouds are the most popular solution out there, particularly as they can be used by almost anyone with varying levels of experience and knowledge on how cloud servers work. Here are the main advantages of public cloud servers:
1. Cost
A public cloud has much lower start-up costs compared to a private cloud. Most solutions work on a monthly payment basis or have a “by-the-hour” usage model. So if you only need to use your public cloud sparingly, then this solution would make more sense. Plus, you won’t have to pay someone else to manage it or implement an infrastructure, as a public cloud comes ready with one to use.
2. Backup potential
Gone are the days of buying USB sticks and external HDs. A public cloud essentially “mirrors” your data wherever the data centre is of your public cloud solution, meaning backups and data restoration is easier to fulfil. This saves time and worry for a business having to back up on external sources, which poses its own security risks.
3. Scalability
Like private clouds, public clouds can be scaled if you need more resources. You can add more CPU, RAM or SSD to the virtual machines whenever you need. Infrastructure costs are shared across multiple users on the public cloud, so the provider will optimise the hardware needs of its data centres and offer the services at lower costs. Plus, you only pay for what you use, and a good public cloud provider will tell you when you’re reaching capacity and will remind you to upgrade.
4. Little to no maintenance
Public cloud providers take care of the upkeep of underlying infrastructure, including hardware updates, security fixes, software patches and more. This shifts the responsibility of maintenance away from the users, giving them the opportunity to focus on their projects or business.
5. Resource sharing
The public cloud allows multiple users to share the same underlying infrastructure and resources, resulting in more efficient resource utilisation. This shared environment also dynamically allocates and distributes resources as needed.
6. New technologies
Public cloud providers are continuously introducing new services, features and updates, giving users access to the latest technology without the need for infrastructure upgrades or maintenance. This encourages innovation and enables companies to rapidly introduce new tools and services to manage their workflow and much more.
7. Reliability
Public cloud providers typically have a robust infrastructure with multiple data centres in different regions across the globe. The advantage to this is that reduced redundancy ensures high availability and fault tolerance, minimising the risk of downtime and data loss. Plus, public cloud providers also offer service level agreements (SLAs) that guarantee certain levels of availability and performance.
8. No commitment
If you’re a small business, it’s likely you won’t want to be tied in, especially if you’re exploring different public cloud options. This is especially true if you don’t want to commit to a specific storage or bandwidth capacity, as you may not know how many resources you need. Public cloud hosting requires no long-term commitments or investments, and typically operates on a pay-as-you-grow model, making the entire onboarding process very easy and hassle-free.
Disadvantages of public cloud
However, there are also several disadvantages of public cloud, including:
1. Security concerns
A public cloud is a shared infrastructure. This means multiple users and businesses share the same underlying hardware and network resources. Naturally, this can raise security and privacy concerns, particularly as sensitive data and applications are stored alongside those of other users. Although cloud providers have strict security measures in place, there’s still the risk of unauthorised access and data breaches.
2. Limited control on infrastructure
Public cloud users have limited control over the underlying infrastructure and systems. This is because a public cloud provider will manage, update and maintain its own infrastructures. While this may be a benefit for many, this can mean less control for businesses that need something more bespoke, particularly if it’s for a specific function or business requirement.
3. Unpredictable costs
It’s true that public cloud services offer scalability and flexibility, but the associated costs can be unpredictable. Your company pays for the resources you consume, so your monthly bill can fluctuate, especially if your usage patterns vary. Additionally, long-term use can be expensive, so it's important to carefully manage resource allocation and not exceed budgets.
4. Migration issues
While you’re not necessarily locked into a plan, a public cloud can make migrating to another provider a headache. This is especially true if you have built specific structures, or rely on add-ons by the original public cloud service provider that may have you “locked in”. Ultimately, this can make migrating to a different provider a lot of hassle, rather than having a bespoke solution that an IT expert can build on a private cloud.
Advantages of hybrid cloud
A hybrid cloud approach incorporates the best of both worlds. Let's dive into the pros of hybrid cloud models.
1. A flexible solution
A hybrid cloud gives you the flexibility to choose where to deploy your workloads based on your specific needs. For example, you can store sensitive or critical data and applications in the private cloud for added security and control, while leveraging the scalability and cost efficiency of the public cloud for non-sensitive workloads. This flexibility allows businesses to optimise their infrastructure according to their needs.
2. It’s a scalable model
A hybrid cloud approach allows businesses to scale resources up or down as needed. If for example, you need to use more resources quickly, a public cloud will allow you to do so, without the time and effort needed to implement this on a private cloud. Or, if you don’t need a public cloud’s resources as much, you can rely on your private cloud during less busy periods.
3. It can be cost-effective
To combine all the advantages above, they can end up being a cost-efficient model if configured correctly. Provided you know which data needs to be housed on a private cloud and public cloud, you can invest in the minimum (or maximum) resources per model, depending on business needs.
4. Control
There’s still an element of control when you choose a hybrid cloud model, which isn’t the case if you opted solely for a public cloud to house all of your business infrastructure. Again, you can pick and choose which data sits on which cloud, and have your IT team configure the private cloud to house specific software, apps, and more, in addition to using your public cloud solution’s add-ons where appropriate.
Disadvantages of hybrid cloud
Of course, there are also some disadvantages to consider when it comes to hybrid cloud:
1. Implementation
Getting started with a hybrid cloud solution can be difficult. This is because you need to know what data, software and allocated hardware solutions you need, and which cloud will have which of these components. If you don’t have the resource or staff to come up with this solution, then it can be difficult to know where to begin.
2. Security
There are security risks with any cloud solution you choose. However, by picking a hybrid cloud solution, you open yourself up to security issues surrounding the data you choose to house on the public cloud servers you use. For example, there could be a cyber attack that puts your business, as well as many others, at risk of a data leak or breach in GDPR.
3. Costs
We mentioned cost efficiency as an advantage previously, but only in the event that the hybrid cloud solution is implemented correctly. Failure to use this model in the best way for your business can mean paying for add-ons already covered by your private cloud, unnecessary usage on the public cloud (which could incur further costs), as well as data breaches if your security measures aren’t implemented correctly. Ultimately, this can harm your business financially, as well as reputationally.
4. Over-dependency
A hybrid cloud relies on network connectivity to transfer data between public and private cloud components, but businesses need reliable, high-bandwidth connectivity to keep things running smoothly. While this is a given, network interruptions and latency issues can affect the performance and availability of hybrid cloud services, leading to possible downtime.
Advantages of multi-cloud
A multi-cloud is a great approach for those wishing to enlist the use of multiple public clouds. Depending on the size, scale and capabilities of your business, the approach will have its advantages and disadvantages. Let’s take a look at the pros first:
1. Pick and choose your public cloud providers
Like the add-ons one cloud provider offers, and the features of another? Multi-cloud gives you more flexibility by allowing you to enlist the help of different cloud providers, without overly relying on just one public cloud for all of your business needs. This enables businesses to choose the best service from a variety of providers based on their specific needs, pricing, performance and much more.
2. More control
Say you have a multi-cloud approach, but one of the public cloud providers ups their pricing or makes a change you don’t like. You may be able to opt-out and find a different provider, or alternatively, migrate your data from that cloud to another you use in the interim.
Plus, this can be a good negotiating tactic when leaving a provider, particularly if price hikes are involved. It could mean the public cloud vendor lets you stay on at the current rate to avoid you migrating your data to another provider.
3. Less downtime
While all cloud deployment options still have a risk of downtime, with a multi-cloud approach, you can still operate part of your business with the other public cloud(s) you use. You may even be able to shift that function to another one of your clouds in the interim too.
4. Cost efficiency
With a multi-cloud approach, businesses can take advantage of competitive pricing models and leverage the scalability of multiple providers to keep costs down. Choose cost-effective options for a variety of workloads and scale resources as needed, without being restricted to a single public cloud.
5. Improved performance potential
Say you operate a part of your business overseas, you can leverage data centres from various public cloud providers across the world. Essentially, this makes it easier to allocate workloads (or house data) to specific providers where those business functions are located. This reduces latency and improves overall performance.
Disadvantages of multi-cloud
There are a number of disadvantages to opting for multi-cloud that need to be taken into account. Let’s take a look at the cons below:
1. Additional training costs
Managing multiple cloud providers can make things complicated, particularly if the right training methods aren’t in place. Staff will need to know how each public cloud provider operates, which cloud is responsible for a specific business function, how to use the tools and APIs presented in each cloud solution and much more. While this may not be an issue if you only have a handful of cloud solutions, if your business (and staff) scale, this can be easily mismanaged.
2. Security risks
As multi-cloud approaches involve using multiple public clouds, it can be hard to keep track of and maintain security measures for each cloud. While it’s generally down to the provider to ensure risks are mitigated, you’re still sharing those spaces with other users. It’s only normal that security risks become a concern over time, especially as each cloud solution will have its own approach to security.
3. Additional cloud costs
It can be easy to lose track of how each public cloud in your multi-cloud approach is utilised. Is one public cloud at capacity? Or is another cloud not being utilised enough? No matter the instance, you could be paying for more than you really need, especially if you’re using only a handful of the public cloud(s) you’re signed up to.
4. Dependency
Much like hybrid and public clouds in general, too much dependency on connecting to the public clouds can be detrimental to business function if you rely heavily on internet access. In contrast, private clouds can be accessed through the internet or a private internal network. So relying heavily on a multi-cloud approach could be detrimental if you’re unable to get internet access.
Frequently asked questions about private cloud and public cloud
Is private cloud cheaper than public cloud?
Private clouds typically aren’t cheaper than public clouds. However, depending on the infrastructure required for your business, a private cloud could work out cheaper in the long run.
This is because public clouds can come with hidden costs, even for something as simple as moving traffic between VMs. Plus, you may have to pay for public cloud management fees on top of the service you’re paying for. When you add this up, it could work out more expensive than investing in a private cloud.
In contrast, a private cloud requires a specific skill set to manage. Namely, an IT department that can regularly maintain the private cloud, install security and software patches, tailor the infrastructure in accordance with business needs, on-demand provisions and much more. If you don’t have dedicated IT personnel, or can’t afford to source the help required, then a public cloud could be a good interim solution.
Is it possible to have private data in public cloud?
Yes, there is nothing to stop you from having private data in the public cloud. In fact, it’s recommended in instances where you do not have security or IT infrastructure in place by dedicated employees who can upkeep a private cloud. Public clouds are specifically managed by the provider’s security experts who are trained on how to mitigate risks.
But there’s still the fact that you’re sharing a public cloud with an unknown number of customers. While every step is taken to ensure there’s no data breach, it’s understandable why growing businesses may choose to have their own internal private cloud instead.
If you decide to use a public cloud to store private data, be sure to check the service level agreement (SLA), and ensure the public cloud solution for your business remains compliant with UK GDPR.
Why would you use a private cloud?
Private clouds are ideal for businesses with more pressing security concerns. Although cloud providers implement robust security measures to prevent data breaches in public cloud servers, there’s still the inherent privacy issue of sharing space with other businesses. Therefore, if a business is within an industry with stricter data privacy and compliance requirements, such as the healthcare and finance industries, private cloud may be the only option.
Plus, with private cloud, you’ll get the benefit of full root access, which means you can customise your cloud environment to suit your exact needs. While being in charge of customising and managing private cloud servers could be daunting to smaller businesses, this task is much more manageable for larger businesses with dedicated IT teams.
Why would you use a public cloud?
For businesses with smaller budgets and no IT teams, public cloud is often the go-to choice. If you don’t mind sharing space with other businesses, public cloud will give you lower startup costs, access to pay-as-you-go models and fantastic scalability. In addition, your public cloud provider will handle maintenance and upgrades for you, giving you more time to focus on other areas of your business. This is also very useful if you have a small team of employees, as you won’t need to spend money on hiring extra IT personnel or training current employees to handle day-to-day cloud server maintenance.
What’s the difference between hybrid cloud and multi-cloud?
Although the terms ‘hybrid cloud’ and ‘multi-cloud’ are sometimes used interchangeably, they’re actually quite different. Hybrid clouds allow businesses to get the best of both worlds by shifting workloads and data across private clouds and public clouds, giving them the privacy, security and control of a private cloud and the cost-effectiveness, scalability and ease of use of a public cloud. Businesses can choose to keep more sensitive data in private clouds while performing other processes in accessible public clouds.
On the other hand, multi-clouds refer to multiple cloud deployments of the same type sourced from different cloud providers. The main advantage of this is that organisations can run different operations in different clouds, tailoring each environment to suit these specific needs. However, one potential problem is that the need for communication between different clouds could cause latency issues.
Now that you know the difference between private cloud and public cloud servers, you can now make an informed decision on which to choose. Talk to our sales team and take your business into the cloud now.