When working in the cloud, it is important to make decisions about its architecture depending on the business and customer data. Because a cost-effective architecture can only give you the key profit with SaaS software. Here we must mention about single-tenant and multi-tenant cloud environments. Both types of architecture have their own advantages and disadvantages depending on the architecture and it’s up to your decision which model you adopt.

In this article, we’ll compare multi-tenant vs. a single-tenant cloud architecture.

Related post – What are SaaS,PaaS and IaaS in cloud computing?

What is a single-tenant application vs. multi-tenant?

Single-tenant cloud architecture is a cloud architecture where only one customer is served by a single software instance and its supporting infrastructure/database. In this architecture, all customer data and interactions are separate from every other customer. Besides, not all customer data is hosted by the same database and there’s no sharing of data in any way. Here each customer has his or her own independent database and instance of the software. There is no common sharing option in this case.

Potential benefits of single-tenant include:

• Security: It high in this scenario as there is no common sharing concept in this architecture. A single customer and a single server is often contained on secure hardware which is used by a limited number of people.
• Dependability: Since an entire environment is dedicated to one client, resources are abundant and available anytime.
• Customization: Since each customer has dedicated software and hardware you can do customization in a single tenant architecture. Here with control over the entire environment more customization is possible.
• Portability – Since in single tenant architecture there is no chance of mixing of multi customer data and data is less it is easier to migrate. In this case, there is no need to write complicated migration scripts. It can also be easier to migrate data from a single-tenant architecture.Lastly, most single-tenant architecture replicate the same infrastructure for each customer; therefore, migrating data is often similar to setting up a new customer..

Potential drawbacks of single-tenant:

• Maintenance: Maintenance is tedious in a single-tenant architecture as it consists more tasks. Also, it needs regular maintenance to keep things running smoothly and efficiently.
• Setup/Management: By comparison, SaaS multi-tenant environments are quick to setup and manage.
• Cost: Single-tenant typically allows for more resources, but at a premium price given that there is only one customer for the entire environment.
• Inefficient resource usage – Though more resources are involved here they are underutilized which leads to inefficiencies. Since customers do not have the same usage patterns, allocating the same amount of physical resources to each customer will result in some customers using all (or even needing more) of their allocated resources while others use little or none of their resources.

A multi-tenant architecture is one where a single software instance and its supporting infrastructure serves multiple customers (i.e. tenants). Each customer shares the software application and also shares a single database. However, each tenant’s data is isolated and remains invisible to other tenants.

We can bring a real estate analogy here to explain single-tenant vs. a multi-tenant cloud architecture. In a single-tenant cloud, each customer lives alone in a single apartment building which has its own security system and facilities and is completely isolated from neighboring buildings.

In multi-tenant cloud architecture, tenants live in different apartments inside a single apartment building. They share the same security system and communal facilities. But each tenant has a key to their respective apartments so their privacy is guaranteed within their apartment. However, the activities of fellow tenants are more likely to have an impact on their comfort in the building.

Most startups opt for a multi-tenant setup, which means having one big database that houses all the customer data. With the right security systems in place, customer data stays private. While customers cannot see each other’s data, they do live in the same database, and the same computer processes all of the data; so, it’s not segmented in any way.

Potential benefits of multi-tenant:

• Affordable Cost: Since multiple customers share resources in the cloud environment cost is also shared. So, savings from the SaaS vendor are typically transferred to the cost of the software.
• Integrations: It is easier to integrate with other applications through the use of APIs within the cloud environment.
• “Hands-free” Maintenance: The server technically belongs to the SaaS vendor, meaning that a certain level of database maintenance is handled by the vendor, instead of you maintaining the environment yourself.
• Easy deployability – Multi-tenancy is at the heart of effective SaaS operations because you can easily build and deploy applications as well scale them. Single tenant approach is not easy for a start up, however,by adopting a multi-tenant architecture they can reach for tools provided by the cloud services provider, such as AWS, and build their application faster.

Potential drawbacks of multi-tenant:

• Limited Management/Customization: You can add integration benefits here but can’t make custom changes to the databases.
• Security: Other tenants won’t see your data. However, multiple users are allowed on the same database. This broader access reduces control of security.
• Updates/Changes: If you rely on integrations with other SaaS products and one updates their system, it may cause issues with those connecting apps.

When To Use Single-tenant Vs. Multi-tenant Architecture

If you have strong security and privacy concerns around customer data then you should opt for single-tenant architecture. Good examples are the healthcare and finance industries.

In the healthcare industry, for example, applications must meet HIPAA requirements when dealing with patient information. So each hospital may need to have its own data center on-site to ensure compliance. The same applies to certain types of financial data.

On the other hand, most consumer-facing applications are best built as multi-tenant applications. Interestingly, the cloud itself is multi-tenant. Cloud service providers such as AWS use the same hardware for various customers under the covers. While each customer has a different Amazon account, the same computers process customer information.