Microservices Security How To Secure Your Microservice Infrastructure?

In today’s market where industries are using various software architectures and applications, it’s almost next to impossible to feel that, your data is completely secure. So, while building applications using the microservice architecture, security issues become more significant, as, individual services communicate with each other and the client. So, in this article on microservices security,  I will discuss the various ways you can implement to secure your microservices in the following sequence.

What are microservices?

Microservices, aka microservice architecture, is an architectural style that structures an application as a collection of small autonomous services, modeled around a business domain. So, you can understand microservices as small individual services communicating with each other around the single business logic. If you wish to know more about microservices in-depth, then you can refer to my article.

Now, often when companies shift from a monolithic architecture to microservices, they see many benefits like scalability, flexibility and short development cycles. But, at the same time, this architecture, also introduces a few complex problems.

So, next in this article on microservices security, let us understand the problems faced in a microservice architecture.

Problems faced in microservices

The problems faced in microservices are as follows:

Problem 1:

Consider a scenario, where a user needs to login to access a resource. Now, in microservices architecture, the user login details have to be saved in such a manner that, the user is not asked for verification each and every time he/she tries to access a resource. Now, this creates a problem, as the user details might not be secure and also could be accessed by the 3^rd party.

Problem 2:

When a client sends a request, then the client details need to be verified and also the permissions given to the client need to be checked. So, when you use microservices, it may happen that for each and every service you have to authenticate and authorize the client. Now, to do this, developers might use the same code for each and every service. But, don’t you think relying on a specific code reduces the flexibility of microservices? Well, it definitely does. So, this is one of the major problems often faced in this architecture.

Problem 3: 

The next problem which is very prominent is the security of each individual microservice. In this architecture, all the microservices communicate with each other simultaneously in addition to the 3^rd party applications. So, when a client logs in from a 3^rd party application, you have to make sure that the client does not get access to the data of microservices, in a way that, he/ she might exploit them.

Alright, the above-mentioned problems are not the only problems found in a microservice architecture. I would say, you could face many other problems related to security based on the application and the architecture you have. On that note, let us move forward with this article on microservices security and know the best way to reduce the challenges.

Best practices for microservices security

The best practices to improve security in microservices are as follows:

Defense in Depth Mechanism

As microservices are known to adopt any mechanism on a granular level, you can apply the Defense in Depth mechanism to make the services more secure. In layman terms, the Defense in Depth mechanism is basically a technique through which you can apply layers of security countermeasures to protect the sensitive services. So, as a developer, you just have to identify the services with the most sensitive information and then apply a number of security layers to protect them. In this way, you can make sure that any potential attacker cannot crack the security on a single go, and has to go forward and try to crack the defense mechanism of all the layers.

Also, since in a microservice architecture, you can implement different layers of security on different services, an attacker, who is successful in exploiting a particular service, might not be able to crack the defense mechanism of the other services.

Tokens and API Gateway

Often, when you open an application, you see a dialog box saying, “Accept the License Agreement and permission for cookies”. What does this message signify? Well, once you accept it, your user credentials will be stored and a session will be created. Now, the next time you go on the same page, the page will be loaded from the cache memory rather than the servers itself. Before this concept came into the picture, sessions were stored on the server-side centrally. But, this was one of the biggest barriers in horizontally scaling, the application.

Tokens

So, the solution to this problem is to use tokens, to record the user credentials. These tokens are used to easily identify the user and are stored in the form of cookies. Now, each time a client requests a web page, the request is forwarded to the server, and then, the server determines whether the user has access to the requested resource or not.

Now, the main problem is tokens where the user information is stored. So, the data of tokens need to be encrypted to avoid any exploitation from 3^rd party resources. Jason Web Format or most commonly known as JWT is an open standard which defines the token format, provides libraries for various languages and also encrypts those tokens.

API Gateways

API Gateways add as an extra element to secure services through token authentication. The API Gateway acts an entry point to all the client requests and efficiently hides the microservices from the client. So, the client has no direct access to microservices and thus in that way, no client can exploit any of the services.

Distributed Tracing and Session Management

Distributed Tracing

While using microservices, you have to monitor all these services continuously. But, when you have to monitor a humongous amount of services simultaneously, then that becomes a problem. To avoid such challenges, you can use a method known as Distributed Tracing. Distributed tracing is a method to pinpoint the failures and identify the reason behind it. Not only this, but you can also identify the place at which failure is happening. So, it is very easy to track down, which microservice is facing a security issue.

Session Management

Session Management is an important parameter that you have to consider while securing microservices.  Now, a session is created whenever a user comes on to an application. So, you can handle the session data in the following ways:

1. You can store the session data of a single user in a specific server. But, this kind of system, completely depends on load balancing between the services and meets only horizontal scaling.
2. The complete session data can be stored in a single instance. Then the data can be synchronized through the network. The only problem is that, in this method, network resources get exhausted.
3. You can make sure that the user data can be obtained from the shared session storage, so as to ensure, all the services can read the same session data. But, since the data is retrieved from shared storage, you need to make sure that you have some security mechanism, to access data in a secure way.

First session and Mutual SSL

The idea of the first session is very simple. Users need to login to the application once, and then they can access all the services in the application. But, each user has to initially communicate with an authentication service. Well, this can definitely result in a lot of traffic between all the services and might be cumbersome for the developers to figure out failures in such a scenario.

Coming to Mutual SSL, applications often face traffic from users, 3^rd parties and also microservices communicating with each other. But, since these services are accessed by the 3^rd parties, there is always a risk of attacks. Now, the solution to such scenarios is mutual SSL or mutual authentication between microservices. With this, the data transferred between the services will be encrypted. The only problem with this method is that, when the number of microservices increase, then since each and every service will have its own TLS certificate, it will be very tough for the developers to update the certificates.

3^rd party application access

All of us access applications which are 3^rd party applications. The 3^rd party applications use an API token generated by the user in the application to access the required resources. So, the 3rd party applications can access that particular users’ data and not other users credentials. Well, this was in respect to a single user. But what if the applications need to access data from multiple users? How do you think such a request is accommodated?

Usage of OAuth

The solution is to use OAuth. When you use OAuth, the application prompts the user to authorize the 3^rd party applications, to use the required information and generate a token for it. Generally, an authorization code is used to request the token to make sure that the user’s callback URL is not stolen.

So, while mentioning the access token the client communicates with the authorization server, and this server authorizes the client to prevent others from forging the client’s identity.  So, when you use Microservices with OAuth, the services act as a client in the OAuth architecture, to simplify the security issues.

Well, folks, I would not say that these are the only ways through which you can secure your services. You can secure microservices in many ways based on the architecture of the application. So, if you are someone, who is aspiring to build an application based on microservices, then remember that the security of the services is one important factor which you need to be cautious about. On that note, we come to an end to this article on microservices security. I hope you found this article informative.

If you wish to learn Microservices and build your own applications, then check out our Microservices Certification Training which comes with instructor-led live training and real-life project experience. This training will help you understand Microservices in-depth and help you achieve mastery over the subject.

Got a question for us? Please mention it in the comments section of ” Microservice Security” and I will get back to you.