The Questions You May Face During Web Services Interview
Are you preparing yourself for an interview pertaining to web services? If you are then it is the right place where you should be. There are various things that you should make yourself prepared before you appear for the interview. Preparing yourself for the web services interview questions is definitely a part of the preparation. There are some other things too that you should be prepared for. Let us see the other things that you should be prepared about before preparing for some of the questions that you may be asked. Do some research about the company where you are going to appear for the interview. There may be some questions upon that too. Plan what you need to wear during the interview. It is best to dress up in traditional business attire. You must have the documents that you need ready at hand so that if required you can produce that. You must also be mindful of the non-verbal communication that you do. The aspects that you must be careful about is the time when you reach the interview venue, your behavior in the waiting room, your seating posture, and be attentive. Now, let us come to the most important part that is to prepare for certain questions that you may be asked.
Explain what is web service?
This may be the first amongst all the web services interview questions that you are asked. Definitely, you must know the answer but to prepare in a proper manner the answer is that it is a nature of software that is available over the net. It uses XML system of messaging and makes available an interface that can be easily understood by end-users.
Explain the working nature of Web service?
This nature of service offers means of communication among various natures of the application by opening standards such as HTML, XML, WSDL, and SOAP. Java based services can be created on Solaris which can be accessed from the visual basic program that runs on Windows. C# can be used for building new web services on Windows which can be used for applications that are based on JSP and that which runs on Linux.
Can you explain the benefits of having Web Services?
There are various benefits that one can have by the usage of this nature of services. The benefits are:
- The existing functions can be exposed on the network: The functionality of the existing code that you are using can be exposed over the network. As this is done the functionality can be used by other applications.
- Interoperability: This service allows communications to happen between different applications and they are able to share the data they are using and the services they are offering.
- Standardised Protocol: The protocol that this nature of service uses for communication is standardised according to industrial norms.
- Cost effectiveness: This is the biggest advantage that web services offer. Having this nature of service gives you the freedom to use SOAP and HTTP protocol and you do not need to have high-speed internet.
Explain Interoperability in Web services?
The questions may be looking to be very basic but it is good to know the proper manner in which it should be answered. The answer to this question amongst the web services interview questions is: Interoperability is a feature of web service which allows various other applications to have effective communication with them. Various other applications can also use this service. For instance, there can be effective communication between VB or.NET applications with that of Java Web service. This helps to make the technology and platform used by applications to be independent.
Can you say what is new in this field of service?
The integration of XML into this nature of service which provides it a solitary language for communication in between the RCP’s used the web service and the directories that are used. This is the new concept that has been integrated during the last few years.
Can you provide an example where real web service is used?
IBM web service is an example where real time web service is used. The way to get access to this nature of service is through the IBM Alphaworks site. You will be able to see various demos pertaining to web service over here. This nature of service can be used having the help of SOAP, WSDL and UDDI. Using these you can have a plug-and-play nature of interface where you can use web services.
Define web services protocol stack.
The questions that we are discussing may seem to be you very basic. Yes, they are and that is the nature of questions that the interviewers ask to ascertain your level of understanding of the subject that you are giving an interview on. The answer to this question is: This is the set or collection of various protocols that can be used to investigate and implement this nature of service. There are four layers in a stack, they are Service transport, the XML messaging, the description and the service discoveries.
Define the layers of a protocol stack.
Yes, this is also a question whose answer is known to you. But for the benefit of others and to be organized during the interview it is good to know the answer. The proper answer to this question amongst the web services interview questions is:
- Service Transport Layer: This helps in transferring messages between the different applications that are used. The different applications that may be used are HTTP, BEEP, FTP and the SMTP.
- XML Messaging Layer: This layer helps to encode the messages in XML format so that they can be understood at each end like as in XML-RCP and SOAP.
- Service Description Layer: This layer is the user interface that is used by the web service like WSDL.
- Service Discovery Layer: This layer helps to centralize the services to a common registry and this helps to have functionality by means of which one can simple publishing feature like UDDI.
I think in between the question I need to clear one thing. It may seem that the answers to all the questions are known. Yes, it may be so but when you seat on the hot seat things get confused. Known things do not come to our mind when it should be and we fumble. This shows to the interviewer that we are not confident about the subject. So, in order to not to be in such a situation, it is better to be organised before any interview and it is good to know how to answer any question in a proper manner.
Can you tell me the nature of security that is needed for web services?
The level of security should be more than SSL. To have such a level of security the usage of Entrust Secure Transaction Platform is required. This nature of security is required so that proper security can be given to any nature of transaction and secures the confidential information.
What is Web API?
Web API is a nature of web service where an emphasis is put on simple nature of REST. XML based protocols like SOAP and WSDL are not required for RESTful API. It generally uses JSON as it is fast and can be read by humans.
Explain what is REST?
For the creation of web service which is scalable the usage of certain guidelines and practices need to be in place. The software architectural style which provides such guidelines and practices is what REST is. It is easy to compare to web services based on SOAP and WSDL. Web pages that use HTTP request generally use REST.
Explains loosely coupled architecture in web services?
One who uses web services is independent of the web service. The interface that is used by the service can be changed but that does not affect the ability of the client to cooperate with the service. On the other hand, a service which is coupled tightly makes the client bound with the logic of the server and so when any interface changes the client must update that for proper working. Having a loosely coupled architecture allows having more manageability of the software and offers a simpler method of integration between different systems.
Explain whether RPC’s is supported by web service?
This may be the nest bomb shell that is thrown at you. If you continue reading you will have the ability to tackle that situation. Having such a service one can call upon different procedures, functions, and various methods on objects which are remote by the usage of protocol based on XML. The parameters pertaining to input and output are exposed by remote procedures which the web service supports. Technologies like EJBs component development and .NET component can be easily spread and accessed by usage of various RPC features. RPC is supported by web service. This is made possible by the provision of service to its own, corresponding to those of a conventional constituent, or by translation of inward bound invocations into an invocation of an EJB or a .NET component.
Mention and explain the behavioural characters of web services?
So, how do you feel about this question which may be one of the web services interview questions? It is pretty difficult to answer these natures of a question if prior preparation is not there. The answer to this question is that the behavioural characteristics of web services are the following:
- XML Based: XML is used for the representation and transportation layers of data in web services.
- Loosely Coupled: The end user is not tied directly to the web service.
- Coarse grained: The exposed business and interfaces must be coarse grained. It provides a natural definition to the coarse grained services and allows it to access the right amount of data.
- Synchronous and Asynchronous ability: The clients who are Asynchronous can recover the result at a later stage. Synchronous clients, on the other hand, get the result as soon as there is a completion of service. This Asynchronous potential is the main factor which makes web services loosely coupled.
- RPC is supported: It supports RPCs.
- Exchange of documents: This nature of service enables transparency in transferring of documents which are vital for having proper integration of business.
Is there any need of having special applications for using web services?
The answer to this question is that there is no necessity of having any special application for using web services. It can be approached from any nature of application which can support appeal and reply based on XML.
Explain the process to document web service?
It is self-documenting in nature as there is complete information pertaining to the methods that are available and the usage of parameters for standards which are based on XML and this is known as WSDL. If you wish you can input more information for the explanation of web service by the usage of attributes of your own web service and web method.
Name the situations when there is a necessity of usage of ASP.NET web services?
If you need to implement architecture which has three tiers then there is a need of ASP. NET web service. Such usage makes possible the usage of the components of the middle tier by using the internet. The biggest benefit of this nature of application is that communication is possible across firewall as there is a usage of SOAP as the protocol for transportation.
Explain the core role of web service architecture?
There are basically three roles which are integrated into the architecture of web service. They are:
- Provider of service.
- Requestor of service and
- Registry of service.
Explain the meaning of DISCO?
Yes, surely this DISCO is not the place where one should dance with the music of DJs. Over here DISCO means discovery. It is a collection of web services which are interrelated. The company that offers web service keeps a DISCO file in its server and that files give the name of all links that are used for providing web service.
So, how is the preparation till now? I think the web services interview questions that we are making available to you will be helping to stand out amongst all the other candidates. Do not memorise the answers but try to understand how it is logically answered. This nature of studying will help you to excel.
Can you explain how .NET web service consumed?
Definitely, you know the answer as web service is the service upon which you specialized. But then also it is better to learn how this question can be answered logically. We know that web services are based on XML standards. So, clients must have a proper understanding of messages which are based of XML for being able to interchange messages. One can use the proxy mechanism that is offered by .NET framework to communicate with the web services. This mechanism which is a proxy in nature has all the relevant information pertaining to sharing of data which can be sued by one using web services.
Can you explain the disadvantages of Response Caching?
You may be astonished hearing such a question. It is always good to know the disadvantage of a system so that proper utilization of the system can be had. This is the reason why such a question is asked. The interviewer wants to gauge the depth of the knowledge that you have regarding the subject. The disadvantages are:
- It is useless when the value amount is extensive.
- Again this process is bypassed when the information source is external and they are not unable to provide information within the parameters that should be applicable.
Can you explain management in terms of web services?
Management in web service is the nature of capabilities which enables one to discover the existence, the availability, the health, the performance, the usage and the control and configuration of a particular web service within the architecture. As web service becomes inevitable for a business this nature of management will be the most useful toll.
There can be various other questions which you can be asked. But we have taken the pain to cover those questions which are generally asked during such an interview.
As you are prepared with such nature of web services interview questions you will have the required confidence and mind set up so that you can face the interviewer. This preparation will make you stand out amongst the other candidates and you will be the one who will be selected by the company for the job. Face the interviewer with that level of confidence that you are the master regarding web services. While answering a question give a proper answer following the logic that no part is left to be answered.
So, now look out for the advertisement for an interview regarding web service. Apply and be the one who excels in all fields not only during the interview but also after having the job.