Introduction to SOA Interview Questions and Answers
The architecture that provides services through a communication protocol is known as Service Oriented Architecture (SOA). The different services are provided independently of different products and technologies. It is implemented using SOAP protocol and can be easily imbibed in different applications. This architecture can assist in building applications that are reusable and interoperable with the specified business functionalities. It can also be built using different languages with SOA principles being followed.
Now, if you are looking for a job that is related to SOA then you need to prepare for the 2020 SOA Interview Questions. It is true that every interview is different as per the different job profiles. Here, we have prepared the important SOA Interview Questions and Answers which will help you get success in your interview.
In this 2020 SOA Interview Questions article, we shall present 10 most essential and frequently used SOA interview questions. These questions will help students build their concepts around SOA and help them to crack the interview.
Part 1 – SOA Interview Questions (Basic)
This first part covers basic Interview Questions and Answers.
Q1. Explain what is SOA governance and what are its functions.
Service Oriented Architecture governance is used to control services in any SOA. Some activities are defined as a part of SOA governance. This includes managing portfolio of services which help in the planning and development of new services and updating the already existing ones. It also includes managing service lifecycle. This means that all updates of services should not interrupt the current customers and their services. Also, SOA provides consistency of all services by applying rules to all created services. With all this, it also offers monitoring services which help the customer to know about the downtimes or underperformance of any system which can be severe for a particular service. As a result, necessary actions can be taken whenever required and all problems occurring can be instantly resolved by checking performance and availability.
Q2. What are the ends, contract, address, and bindings?
The service can be made available to clients from different ends. All these services must be exposed through one of these ends.
The end will consist of the following:
- Contract: It is an agreement which is agreed upon between two parties. It defines how clients are expected to communicate. It specifies the different parameters and returns values that are to be used.
- Address: This specifies where a user can find a service. There is an address URL which points to the location of services.
- Binding: This determines how to access the end. It specifies the process for communication and how it is to be done.
Q3. How can you achieve loose coupling in SOA?
To achieve loose coupling you can use service interface like WSDL for a SOAP web service. To limit the dependency, you can hide the service implementation from the consumer. Loose coupling can be handled by encapsulating different functionalities in a way in which it will limit the impact of changes to the implementation of different service interfaces. Also, sometime you may have to change the interface and manage versioning without impacting the customers. Also one can manage multiple security constraints, multiple transports, and other specifications.
Q4. Are web services and SOA the same?
SOA is an architectural concept while web services are used to complete them. Web services are the preferred standards that are satisfied to achieve the architectural specifications of SOA. When one uses SOA all services need to be loosely coupled. Also, SOA services should be able to describe themselves and WSDL services will be describing how we can access the services. Also, these services can be accessed through WSDL. SOA services are located in a directory and here UDDI describes where these web services can be found.
Q5. What is a reusable service?
Reusable service is a stateless functionality that has the required granularity. It can be a part of a composite application or composite server. A reusable service should be identified with any activity prescribed by business and which has its specifications. A service constraint may be security, QoS, SLA or any usage policies. It may be defined by different runtime contracts, multiple interfaces, and different implementations. A reusable service is looked over by enterprise-level throughout its lifecycle, starting from design time through its runtime. Its reuse should also be promoted through a pre-defined process and its reuse can be measured.
Part 2 – SOA Interview Questions (Advanced)
Let us now have a look at the advanced Interview Questions.
Q6. Explain Business Layers and Plumbing Layers in SOA.
SOA architecture can be divided into two layers. The first layer shows direct relevance to any business and it carries out different business connections. The second layer is a technical layer tells about how to manage the different computer resources that we have like a database, web server, etc. This segregation is done in order to identify any particular service. Consider any simple system like order management system. It will have many components which interact with each other to complete the system. The two layers of this system will be where plumbing layer will contain data access layer, AJAX and many other functionalities.
Q7. What are the disadvantages of SOA?
The main disadvantage of SOA is to see SOA as an end. Due to this developers tend to create complex unmanageable and unnecessary interconnections between resources. Instead, the developer can focus on the business problem that is existing. Another disadvantage can be that rather than solving small pieces of problem you can take the top-down approach where major companies invest and very often fail to show desired results where there is the relevant timeframe.
Q8. Explain what is a composition of service.
By using composition services are combined to produce composite applications. This application consists of an aggregation of services where an enterprise portal or process is created. A composite service consists of an aggregation of different services which will provide reusable services. It acts like combining electronics components and create reusable composite services.
Q9. What is ESB and where does it fit in?
ESB stands for Enterprise Service Bus. Unlike other relationships, it provided any to any connectivity between different companies. Also, you may need to consider deployment services, IT services, etc. The SOA architecture enables SOA to meet all life’s priorities. The ESB is part of this reference architecture and provides the backbone of an SOA but it should not be considered an SOA by itself.
Q10. In SOA do we need to build a system from scratch?
No, if we need to integrate any existing system you just can loosely couple wrappers which help in wrapping all customer services and expose all functionalities in a generic manner.
This has been a guide to the list Of SOA Interview Questions and Answers so that the candidate can crackdown these SOA Interview Questions easily. Here in this post, we have studied top SOA Interview Questions which are often asked in interviews. You may also look at the following articles to learn more –