Public cloud options have rapidly become the norm in many businesses — rather than needing their own physical infrastructure (including servers), companies find it much easier to outsource to big players like Amazon, Microsoft, and Google. They maintain the platform, letting customers access their services/resources without the need to host it on their own company’s physical premises.
Cloud operators offer several functions to their clients, such as deploying virtual machines/appliances, hosting app servers (including data stores), delivering enterprise and global-level services, providing storage capacity and identity and security solutions, extending data centres to the cloud, and providing backup and site recovery features, which benefit from cloud-native software-development platforms offered by the cloud. The list of benefits is large and new services are frequently introduced.
Many organizations worldwide have either completely migrated or partially migrated to the public cloud of their choice. Those who haven’t migrated their workloads yet are seriously considering this option and are in the process of evaluation, exploration, and developing migration strategies.
But is it appropriate for all enterprises? Are there reasons to keep your assets/workloads locally?
What if there was a compromise option?
What is hybrid cloud?
If public cloud is the behemoth that offers services and resources to clients (small or large) around the world who want them, then private cloud is your traditional on-premises infrastructure. It is more restricted in terms of what it can offer, because it’s only aim is to serve a specific set of users.
But private cloud struggles to cope with bottlenecks when the number of users and their resource requirements grow. It also has reduced functionality, and may not have the same options when it comes to a wide variety of functions, like cloud-native services, data storage, or app services.
Hybrid cloud is essentially a mix of public and private cloud. You can maintain your own data centre, with your own specialized set of functions or services, but at the same time provide access to the services provided by public cloud.
Many different types of hybrid cloud
There are many different ways to implement hybrid cloud, depending on the needs of the users. The most common approach is to buy a specialized hardware unit from vendors, which is supported by your public cloud provider. This specialized hardware unit usually consists of a proprietary operating system, multiple servers, internal switches, built-in redundant power-supply units, hypervisor software, management consoles, and a few more items.
The hardware unit supports scalability and can work in both connected and disconnected modes. Here, connected means having an active connection with the public cloud. This allows you to access public cloud features and benefits without having to worry about the implications of keeping assets outside of your data centre.
A typical hybrid cloud example would be when your data centre isn’t actively connected to the public cloud all of the time, but you do have the option of manually downloading the latest services and updates to your hardware. This enables your users to enjoy the benefits of the public cloud, run locally.
Or, you may need to serve more users but lack the necessary resources. In these cases, you could connect your data centre with the public cloud in order to take advantage of public cloud’s hyper-scale data centres (theoretically infinite resources), which we discussed in my previous APNIC blog post.
There are other variations on approaches to hybrid cloud, depending on how connected they are with the public cloud, and how much control you are willing to share with the public cloud provider.
A hybrid cloud approach brings agility and control of resources in your hands. Along with public cloud services, you can continue to offer customized/specialized services from your existing data centre to your users.
Now let’s examine the advantages and disadvantages of hybrid cloud.
Compliance — meeting requirements around how data is stored and accessed — is usually the most convincing factor that stops organizations from relying solely on the public cloud, and it’s why they look for alternative options, including hybrid cloud.
Depending on the nature of the business and type of data or assets, organizations may be subject to compliance requirements. These compliance issues can be industry/trade specific or of a legal nature. In addition to this, some organizations enforce strict security compliance, which forbids them from keeping any of their assets (keys, data, apps, and so on) on someone else’s hardware, which is unavoidable when using public cloud.
Compliance issues may also explicitly forbid them from keeping copies of user credentials, profiles and other personal data in the public cloud, no matter how secure the public cloud is.
Data sensitivity and sovereignty
If your organization/business deals with sensitive data, such as trade secrets or people’s personal information, there may be additional reasons to explore private and hybrid cloud options. This is similar to issues of compliance in some respects, but it has added cross-border complications.
Different jurisdictions have different laws around data privacy and security (the European Union’s General Data Protection Regulation, for example) and this may have implications for whether or not it’s legally permissible to use public cloud, because the public cloud data centre may be located in a different jurisdiction where the laws differ. In these cases, either private or hybrid cloud may be necessary.
Connectivity with public cloud
A public cloud solution may require 24-hour uninterrupted connectivity, depending on the kinds of services needed. A hybrid cloud may offer more flexibility. This is very useful for remote and mobile data centres (which can be located anywhere) as they are not required to maintain connectivity, so updates and new services can be downloaded and imported using manual methods from the public cloud, as required.
In situations where the service doesn’t tolerate latency (delay), due to the nature of the work (like mission-critical apps), the public cloud may not serve the purpose. Running cloud services in a private or hybrid data centre can significantly reduce latency values due to localized hardware processing.
Maintenance and troubleshooting
One downside of private and hybrid cloud approaches is the need for greater skills relating to maintenance and troubleshooting. Remote support from the cloud operator and hardware vendors may be available, but at the end of the day it is your hardware/infrastructure and if something goes wrong, it’s your problem to deal with.
This also means hiring skilled employees and training them with the latest cloud offerings, services, and their configurations. On the plus side, you will be less reliant on the cloud operator’s technical staff for maintenance and troubleshooting of your hardware, virtual appliances, and assets.
Availability and Service Level Agreements
If you’re using public cloud services but not running those over public cloud infrastructure, you won’t qualify for the Service Level Agreement (SLA) offered by the cloud operator. Maintaining ‘availability’ (up time) is one of the factors of the SLA, and that is in your hands now.
Similarly, ensuring data replication, backups, and site recovery are all your responsibility too.
However, I personally consider this an advantage because a realistic estimation of down time/maintenance outages can be calculated based on the hardware and infrastructure you can touch/see in your data centre. It’s much harder to make those estimates for public cloud resources that you’re unfamiliar with and have limited access to.
The total cost of ownership is probably going to be much higher if you opt for hybrid cloud over the public cloud. There is the cost of the hardware/infrastructure to consider, as well as its maintenance.
However, at the end of the day, you own it. This gives you total control of your assets, and how and where you want to use them. You can customize the hardware as required by your own policies and environment. The only billing matter you need to consider is the subscription for acquiring cloud services from the operator (unlike metered billing of public cloud, hybrid cloud uses an equipment capacity-based billing approach).
In hybrid cloud, your resources are isolated and walled off from strangers as well. On the public cloud, you may be unknowingly sharing the same physical server with your competitor when hosting virtual machines or containers. ‘Physical resource isolation’ is the key advantage in these cases.
That’s it from me! I hope you enjoyed reading this blog. Please keep learning and broadening your knowledge using APNIC resources.
Azhar Khuwaja is a Telecom/IT Trainer with over 20 years of industry and training experience.
The views expressed by the authors of this blog are their own and do not necessarily reflect the views of APNIC. Please note a Code of Conduct applies to this blog.