A multi-tenant architecture is a cloud-oriented application architecture that involves a single instance of the application but serves multiple clients or organizations. The basic idea of this SaaS architecture design is simple: have a single codebase that runs for all clients with the same data structure, but the data layer is separated into different workspaces by each organization.
With a SaaS application that uses a multi-tenant architecture, the software and web development teams will need to implement and support a single codebase and not multiple copies. In this way, we can update the SaaS application simultaneously for all organizations, and it will be easier to manage the server infrastructure.
Some classic examples of the use of multi-tenant architecture are Salesforce, an industry standard in providing CRM services; Netflix, a popular streaming service; Slack, a business communication software; and other giants like Hubspot, Office 365, Box, Zoho, and Zendesk.
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A single-tenant SaaS application is a cloud computing model where each client or customer has their own independent instance of the software and the underlying infrastructure. In a single-tenant environment, the software and its supporting infrastructure are dedicated to a single customer. This means that each customer’s data, application, and server are isolated from those of other customers, providing a higher level of security, privacy, and customization that can be important for certain user cases
In a single-tenant SaaS setup, the service provider manages, updates, and maintains separate instances of the software for each customer. This architecture allows for changes to be made to one instance without affecting others. Additionally, because the resources are not shared with other tenants, clients may experience better performance and have more control over the upgrade cycles and maintenance windows of their SaaS applications.
However, single-tenant SaaS also has some drawbacks. The dedicated nature of the resources means higher costs for both providers and clients, as the economies of scale achieved with multi-tenant architectures are not possible. Dedicated resources may not be fully utilized, leading to inefficiency. Because each instance must be updated individually, it can be slower to roll out new features and updates. Finally, managing multiple separate instances can be more complex and time-consuming for providers.
The primary difference between single-tenant and multi-tenant SaaS architectures lies in how resources, software, and infrastructure are shared among clients.
Using a multi-tenant approach for SaaS architecture can help organizations scale their software more easily and manage a large client base more efficiently. Key benefits include:
Ease of implementing updates
One of the most significant benefits of using a multi-tenant application architecture is updating the application platform for all the clients at once. In the past, updates had to be installed on every client’s computer on which the application was installed. It is now possible to do this for all users at the same time. Customers prefer software that provides frequent and streamlined updates without any effort on their end..
Automated customer onboarding
Using the multi-tenant architecture, SaaS providers can develop a fully automatic customer onboarding process—the user registers, makes the payment, a tenant is added in the software, and the user receives an automated email with their access data.
Long-term cost savings
Multi-tenant architectures help reduce costs in several ways. It allows more efficient usage of resources as the application scales, ensuring a lower cost per tenant. In addition, onboarding, maintenance, and support become much easier and require less manpower on the provider’s side.
If you have a single instance of software, you need to consider how to separate the data between different tenants. There are three common strategies to solve this problem: foreign key, segregated schema, and segregated database.
This is the simplest way to separate data from our different tenants. Each table involved in the application has a foreign key to a tenant’s control table with this strategy. Thus, all data from all the tenants is kept in the same database, segregated by this foreign key. When a user accesses the application, the application checks the tenant linked to the user and shows data from tables whose rows had the foreign key linked to the user’s tenant.
The advantage of this strategy is that its implementation is straightforward and cheap—it only involves foreign keys and filters. However, this strategy has two downsides:
Therefore, this strategy is not recommended for applications with a large volume of data or tenants.
The database instance is still shared among all the tenants in this strategy. But here, each tenant has its own schema. The application is the same for everyone, but that application instance has multiple sets of isolated application tables for each tenant.
The main advantage of this strategy is the isolation of data from different tenants, which reduces the possible impact that a tenant can have on other tenants of the application. For example, accidental deletions would be restricted to the tenant/schema that caused it due to the use of different schemas. This method is an inexpensive strategy as it is based on a single database instance. However, it has a slightly more complex implementation.
Each tenant has a dedicated database instance in this strategy—the application can simultaneously connect to multiple databases.
The main advantage of this model is that isolation is now “physical”, with each tenant having their own unique database instance. This further mitigates the chances of one tenant’s operations impacting the experience of other tenants. The performance gain in this strategy is also noticeable since there are isolated database instances for each tenant.
However, this strategy is significantly more complicated to implement: the application will have to connect to multiple databases simultaneously according to the user accessing the application. In addition, you will need to provision a database instance for each tenant, which makes this the most expensive strategy among the three we discussed.
To efficiently manage resource utilization in a multi-tenant SaaS environment, it’s essential to implement resource quotas for each tenant. Resource quotas help ensure that no single tenant can monopolize system resources, leading to a fair and balanced distribution. Here’s how to effectively set and manage resource quotas:
Creating a tenant-aware application design involves tailoring your application architecture to recognize and respect the multi-tenant nature of your SaaS platform. Here are key considerations:
Versioning policies are crucial for maintaining stability and consistency in a multi-tenant SaaS application. Here are steps to develop effective versioning policies:
Effective monitoring is essential for maintaining the health and performance of a multi-tenant SaaS application. Here’s how to set up a comprehensive monitoring system:
Tenant-specific logging and auditing are vital for ensuring security, compliance, and operational transparency in a multi-tenant SaaS application. Here’s how to implement these practices effectively:
In a nutshell, Frontegg’s PLG-centric and end-to-end user management platform is multi-tenant by design.
By developing the platform to the essential requirements of the B2B SaaS, we know that each tenant has its own configurations, user sets, and security settings. This is why Frontegg allows each environment to hold segregated sets of tenants, assign users to each one of them, and hold a separate configuration for each one of them in a way that doesn’t affect the neighboring tenants in any way or form.
In the complex B2B world, each customer requires fine grained control on each configuration. That requires professional products to keep pace with these requirements and develop a multi-tenant capable infrastructure from day 1. Frontegg just makes it easier.
