Microservices have redefined application development. Unlike monolithic applications that incorporate all the code and components within a single architecture, microservices are smaller, autonomous modules of a more complex system. That makes them a good option for developers to rapidly deploy secure and reliable applications.

Because of its inherent benefits over monolithic architectures, microservices are experiencing widespread adoption by several organizations and developers. In an O'Reilly survey in 2020, nearly one-third of respondents (29%) say their companies will migrate to using microservices, and 50% say they will use them primarily for all of their systems. Despite this popularity, microservices still face several risks and vulnerabilities due to their multiple points of entry. With that in mind, enforcing the best practices for microservices security must be a top priority for any organization.

As a CTO, you're responsible for the security of your company's data and assets. Failure to protect your microservices from attacks or threats may have devastating consequences on your business. In this article, you'll find out why microservices are more secure than monolithic architectures.

What Is Microservices Architecture?

Microservice architecture is an application design process that involves breaking down monolithic applications into loosely coupled and independent modular, distributed services that are scalable and deployable. To sum that up, microservices consist of multiple lightweight services that communicate via APIs. 

The services are managed in a centralized manner even though they may be written in separate programming languages technology stacks and stored in different databases. Because of its independent nature, you can update and add new functionalities or features without affecting the entire application.

Advantages of a Microservice Architecture Over Monolithic Architecture

Microservice architecture has several benefits over traditional monolithic architecture. Here are some of them:

Autonomy

Microservices provide you with control over the choice of language, database, framework, technology stack, or third-party libraries. As a result, you can set up cross-functional and independent teams to handle different microservices and components without affecting others. 

Monoliths lock you in on framework, programming language, technology stack, and database. Once you've decided on those, it's nearly impossible to make changes without breaking some functionalities or services within your architecture. 

Independent Scalable Structure

You can rapidly scale up or scale down your microservices architecture. Traditional monoliths share a single database and a single programming language. Meanwhile, each microservice can have its database and any programming language. 

Making changes to languages or stacks of monolithic architectures can be challenging. With microservices, you can easily modify the architecture without affecting the entire system. You also decrease the likelihood of a single server failure taking down your entire system by separating parts of it across multiple servers and allowing those services to scale based on demand.

Faster Upgrades

While working in monoliths, updates can take longer to take effect because of the ubiquitousness of the whole system. You must build and run the entire application during every single update. 

In a microservice architecture, you only need to modify that particular microservice without affecting the rest. That equals faster upgrades and improvements for your application.

Rapid and Continuous Deployment

Since each microservice is independent of the other, you can quickly build and deploy applications. In addition to that, you can have separate teams working on each microservice, enabling them to work on any different tech stacks or programming languages.

Monolithic architecture takes longer to deploy. Even with that, you have to ensure you hire developers with knowledge of your tech stack or train them before they start working on it. That can lead to a drop in productivity. 

Inherently Secure

Monolithic architectures consist of a single large, integrated system. Any error can lead to downtime for the entire application. It's a complex architecture which means you must thoroughly test any code change before deploying to production.

On the other hand, microservices consist of independent components. A failure in one service does not necessarily imply the same in another. For instance, if a publishing microservice is down, others will still run since they are independent. That means a smaller blast radius compared to monoliths. 

Security Challenges To Consider

• Multi-Cloud Deployments: Since microservices are deployed across many data centers, host machines, and cloud providers, there's always a risk that you'll lose control and visibility of the components. 

• Data Management: Data in a microservice architecture is quite dynamic. That means they can interact, move, and change across several different components and databases. How can you guarantee data security when a great deal of dynamism is involved? That's not all. With its multiple points of entry and communication channels, you are vulnerable to data leaks.

• The Rapidly Changing Security Landscape: Modern SDLC requires developers to grow an application––code and data– over time. The iterative and incremental approach to development places constant pressure on microservices. Every time you make an addition or iterate, you'll be at risk of exposing your application to a new set of security flaws and attacks.

Microservices Security Best Practices

Because of the multiple entry points and connections, you should always be up-to-date on new security mechanisms that can help safeguard your application. Here is a list of 7 microservices security best practices to follow to guarantee utmost protection.  

Design a Secure Architecture From The Start

The goal of securing your microservice architecture should be in place from the start. You don't want to wait till your application is in production or ready to go live before putting the appropriate measures in place. That means you should keep security as a priority the moment you start developing your application.

To further ensure security, you should implement continuous monitoring tools and principles into your CI/CD pipeline. Build unit tests into your pipeline to help limit the number of manual security checks for your developers.

Follow a DevSecOps Approach

Similar to securing your application from the start. DevSecOps is a development methodology that builds security into your entire application development pipeline. In this process, the development team collaborates with the security team from the start of the application rather than waiting until it is ready for production.

In addition to this, you should continuously monitor your pipelines through CI/CD and in production. The same is true for third-party libraries and extensions. By doing this, your application architecture is continuously secure, making it easier to identify and review vulnerabilities and loopholes.

Build API Gateways

Microservices typically operate across a variety of technology platforms, networks, databases, interfaces, and protocols. As a result, there are multiple API points of entry. To efficiently secure these points from any attack or vulnerability, be sure to enforce authentication and authorization to those points through a single entry point--API gateway. 

By enabling authorization points, you can control access to sensitive resources and assign different roles and services. Another benefit you get with API gateways includes cookies, request caching, monitoring, and routing.

Secure Your Containers

Most microservices reside in containers. Because of this, container security is equally important. That security also applies to complete containerized environments such as registries, orchestration, and container images. The container images are often open to vulnerabilities. 

To secure your containers, be sure to regularly scan your container for flaws and ensure you don't use container images with security vulnerabilities or issues. To further guarantee container security, enforce constraints on the use of resources, such as limiting container access to the host OS. To top it off, separate resources with varying degrees of sensitivity using appropriate rules.

Scan for Dependencies

Almost every application in production depends on one or more third-party libraries or dependencies. These libraries can pose significant risks to your microservices. To mitigate these security risks, use a scanning or monitoring tool to regularly check and validate every line of code, dependencies, and third-party libraries. Such tools also provide automated security updates and notifications.

Use Access and Identity Tokens

It's only smart to limit access to microservices architecture because it encompasses everything from backends to third-party libraries, databases, and user interfaces. To do that, you should strengthen the security of your microservices by setting up the right authentication & authorization protocols to keep out unwanted access. 

In addition to that, you can set up a Multi-Factor Authentication (MFA) process by adding a layer of authentication to the traditional login credentials. MFA ensures that only authorized users can access the system. You can also set up biometric authorization.

Leverage Application Security Testing Tools

Due to their distributed nature, microservices are challenging to monitor and protect without an effective monitoring tool. Since more and more vulnerabilities are appearing, incorporating security testing or monitoring tools into your DevOps pipeline is crucial.

Use a comprehensive service to enable continuous improvement in your DevOps pipeline by monitoring the security and availability of your application. A monitoring tool will provide you with complete security coverage of your application and customer data. Also, you get complete visibility and transparency to reports and dashboards that provide access to timely and accurate information about the status of your application.

To cap it off, It also helps you carry out penetration testing, compliance, and patching, among several other functions. Failure to be compliant can be extremely devastating for a business. To learn why compliance and governance are crucial, look at the 5 Major General Data Protection Regulation Breaches That Led to Huge Penalties.

How To Implement A Secure Microservice Architecture

Changing from a monolithic to a microservice architecture can seem daunting. To facilitate a better transition, be sure to stay organized and implement the following:

• Choose your microservices for their ability to perform one specific function. Don't break them down into redundant and inefficient subcategories.

• Implement microservices security best practices and use a security or monitoring tool. Since microservices span across different data stores, languages, and contexts, it is a huge challenge to ensure security across the entire architecture. Also, have a look at the OWASP Top 10 web application security risks and how you can prevent them.

• Whenever possible, do not repurpose logic from one application to another. When more than one microservice has the same common element, make each one different by rewriting it.

• Be sure to have DevOps and Container management experts in implementing your microservice architecture. Microservice applications are hazardous to build without sufficient skills and knowledge. When required, don't hesitate to have domain experts to cater to microservices that need domain knowledge. 

• It's best to have a microservice tied to one database or a particular context at a time. That way, you'll minimize blast radius so any breaking changes or vulnerability won't affect other services.

If you want to read more about Zesty.io’s security policies, take a look at this article: What is OWASP Security?